Zenas BioPharma, Inc. 10-K

Zenas BioPharma, Inc._December 31, 2024 Table of Contents ​ ​ UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ​ FORM 10-K ​ ​ (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-42270 Zenas BioPharma, Inc. (Exact name of registrant as specified in its charter) ​ ​ Delaware 93-2749244 (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification Number) ​ 852 Winter Street , Suite 250 Waltham , MA 02451 (Address of Principal Executive Offices) ( 857 ) 271-2954 (Registrant’s telephone number) Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐ No ☒ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No ☒ Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☐ No ☒ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. ​ ​ ​ ​ ​ ​ ​ Large accelerated filer ☐ Accelerated filer ¨ ​ ​ Non-accelerated filer ☒ Smaller reporting company ☒ Emerging growth company ☒ ​ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐ If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐ Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒ Securities registered pursuant to Section 12(b) of the Act: ​ ​ ​ ​ Title of Each Class Trading symbol Name of Exchange on which registered Common stock, par value $0.0001 per share ZBIO Nasdaq Global Select Market ​ ​ The registrant was no t a public company as of the last business day of its most recently completed second fiscal quarter and, therefore, cannot calculate the aggregate market value of its voting equity held by non-affiliates as of such date. The number of shares of Registrant’s Common Stock outstanding as of February 28, 2025 was 41,799,336 . Documents Incorporated by Reference Portions of the Registrant’s definitive proxy statement relating to the 2025 Annual Meeting of Stockholders, which will be filed with the Securities and Exchange Commission within 120 days after the end of the Registrant’s fiscal year ended December 31, 2024, are incorporated by reference into Part III of this Annual Report on Form 10-K. ​ ​ ​ Table of Contents TABLE OF CONTENTS ​ ​ ​ Page PART I ​ ​ ​ Item 1. Business 6 ​ ​ Item 1A. Risk Factors 60 ​ ​ Item 1B. Unresolved Staff Comments 117 ​ Item 1C. Cyber Security 117 ​ ​ Item 2. Properties 118 ​ ​ Item 3. Legal Proceedings 118 ​ ​ Item 4. Mine Safety Disclosures 118 PART II ​ ​ ​ Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities 119 ​ ​ Item 6. Reserved 119 ​ ​ Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations 120 ​ ​ Item 7A. Quantitative and Qualitative Disclosures About Market Risk 133 ​ ​ Item 8. Financial Statements and Supplementary Data 134 ​ ​ Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure 169 ​ ​ Item 9A. Controls and Procedures 169 ​ ​ Item 9B. Other Information 169 ​ ​ Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 169 PART III ​ ​ ​ Item 10. Directors, Executive Officers and Corporate Governance 170 ​ ​ Item 11. Executive Compensation 170 ​ ​ Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters 170 ​ ​ Item 13. Certain Relationships and Related Transactions, and Director Independence 170 ​ ​ Item 14. Principal Accounting Fees and Services 170 PART IV ​ ​ ​ Item 15. Exhibits and Financial Statement Schedules 170 ​ ​ Item 16. Form 10-K Summary 174 ​ ​ Signatures 175 ​ ​ Index to Consolidated Financial Statements 134 ​ ​ 2 Table of Contents SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS This Annual Report on Form 10-K (“Annual Report”) contains forward-looking statements. All statements other than statements of historical facts contained in this Annual Report are forward-looking statements. In some cases, forward-looking statements can be identified by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions, although not all forward-looking statements contain these words. Forward-looking statements include, but are not limited to, statements concerning: ​ ● the commercial opportunities stemming from the development of obexelimab for multiple immunology and inflammation (“I&I”) diseases; ● ​ our ability to develop and, if approved, ultimately commercialize obexelimab and, with partners, our other programs; ● ​ our ability to obtain or maintain orphan drug designation for certain of our product candidates; ● ​ the initiation, timing, progress, results, and cost of our development programs, and our current and future preclinical and clinical studies, including statements regarding the timing of initiation and completion of our clinical trials, and the period during which the results of the trials will become available; ● ​ the success, cost and timing of our clinical development of our product candidates; ● ​ our ability to establish clinical differentiation of our product candidates; ● ​ our ability to develop product candidates that have broad therapeutic potential; ● ​ our ability to utilize our business development strategy and expertise to build a balanced portfolio; ● ​ our ability to identify collaborations and strategic partnerships to maximize the value of our portfolio; ● ​ our ability to build our operational and commercial capabilities for supplying and marketing our products, if approved, in key markets; ● ​ market conditions in the biopharmaceutical sector and issuance of securities analysts’ reports or recommendations; ● ​ the trading volume of our common stock; ● ​ an inability to obtain additional funding; ● ​ our ability to initiate, recruit and enroll patients in and conduct our clinical trials at the pace that we project; ● ​ our ability to obtain and maintain regulatory approval of our product candidates, and any related restrictions, limitations or warnings in the label of any of our product candidates, if approved; ● ​ our reliance on third parties to manufacture drug substance and drug product for use in our clinical trials; ● ​ our ability to retain and recruit key personnel; ● ​ our ability to obtain and maintain adequate intellectual property rights; ● ​ our expectations regarding government and third-party payor coverage and reimbursement; 3 Table of Contents ● ​ our estimates of our expenses, ongoing losses, capital requirements and our needs for or ability to obtain additional financing; ● ​ our existing cash and the sufficiency of our existing cash and proceeds from future capital-raising efforts, if any, to fund our future operating expenses and capital expenditure requirements; ● ​ the potential benefits of strategic collaboration agreements; ● ​ our ability to enter into strategic collaborations or arrangements, including potential business development opportunities and potential licensing partnerships, and our ability to attract collaborators with development, regulatory and commercialization expertise; ● sales of our stock by us, our insiders or our stockholders, as well as expected lock-up releases or expiration of market stand-off or lock-up agreements; ● ​ our expectations regarding the time during which we will be an emerging growth company and smaller reporting company under the Jumpstart Our Business Startups Act of 2012, as amended (the “JOBS Act”); ● ​ general economic, industry, geopolitical and market conditions, such as military conflict or war, inflation and financial institution instability, or pandemic or epidemic disease outbreaks, many of which are beyond our control; ● ​ additions or departures of senior management, directors or key personnel; ● ​ our financial performance; ● ​ developments and projections relating to our competitors or our industry; and ● ​ other risks and uncertainties, including those included in the section titled “Risk Factors.” The forward-looking statements in this Annual Report may prove incorrect. These forward-looking statements speak only as of the date of this Annual Report and are subject to a number of known and unknown risks, uncertainties and assumptions, including those described under the sections titled “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and elsewhere in this Annual Report. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this Annual Report and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain, and should not be unduly relied upon. Because forward-looking statements are inherently subject to risks and uncertainties, some of which cannot be predicted or quantified and some of which are beyond our control, these forward-looking statements should not be relied upon as guarantees of future events. The events and circumstances reflected in our forward-looking statements may not be achieved or occur and actual future results, levels of activity, performance and events and circumstances could differ materially from those projected in the forward-looking statements. Moreover, we operate in an evolving environment. New risks and uncertainties may emerge from time to time, and management cannot predict all risks and uncertainties. Except as required by applicable law, we do not undertake to publicly update or revise any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise. ​ 4 Table of Contents SUMMARY RISK FACTORS ​ Our business is subject to a number of risks of which investors should be aware before making an investment decision. These risks are discussed more fully in Part I, Item 1A. “Risk Factors” in this Annual Report. These risks include the following: ​ ● We are a clinical stage biopharma company with a limited operating history and no products approved for commercial sale; we have incurred substantial losses since our inception, and we anticipate incurring substantial and increasing losses for the foreseeable future; ● We will require substantial additional financing to achieve our goals, and failure to obtain additional capital when needed, or on acceptable terms, would cause us to delay, limit, reduce or terminate our product development efforts; ● Raising additional capital may cause dilution to our stockholders, imposing restrictions on our operations or require us to relinquish rights to our product candidates; ● Clinical development is lengthy and expensive, characterized by uncertain outcomes, with results of earlier studies and trials often failing to predict future trial results or results in other indications of a product candidate. We may incur additional costs or experience delays in completing, or fail to complete, the development and commercialization of our current product candidates or any future product candidates; ● Delays or difficulties in the enrollment and dosing of patients in clinical trials, delay or prevent receipt of necessary regulatory approvals; ● ​ Any significant adverse events or undesirable side effects caused by our product candidates may delay or prevent regulatory approval or market acceptance of our product candidates, or result in significant negative consequences following marketing approval, if any; ● We face potential competition from different sources that have made substantial investments into the rapid development of novel treatments for immunological indications, including large and specialty pharmaceutical and biotechnology companies, many of which already have approved therapies in our current indications; ● We may not realize the benefits of our current or future collaborations or licensing arrangements and may be unsuccessful in consummating future partnerships; ● Even if we complete the necessary clinical trials, we cannot predict when, or if, we will obtain regulatory approval to commercialize any product candidate in the U.S. or any other jurisdiction, and any such approval may be for a more narrow indication than we seek; ● We are dependent on the services of our senior management and other clinical and scientific personnel, and if we are not able to retain these individuals or recruit additional management or clinical and scientific personnel, our business will suffer; ● We will need to grow our organization, and we may experience difficulties in managing our growth and expanding our operations, which could adversely affect our business; ● The manufacturing of our product candidates is complex, and our third-party manufacturers may encounter difficulties in production. If our third-party manufacturers encounter such difficulties, our ability to provide supply of our product candidates for clinical trials, our ability to obtain marketing approval, or provide commercial supply of our products, if approved, could be delayed or halted; 5 Table of Contents ● If we are unable to obtain and maintain sufficient intellectual property protection for our product candidates or any future product candidates we may develop, or if the scope of the intellectual property protection obtained is not sufficiently broad, our competitors or other third parties could develop and commercialize products similar or identical to ours, and our ability to successfully develop and commercialize our product candidates may be adversely impacted; ● ​ We have relied and expect to continue to rely on third parties to conduct our preclinical studies and clinical trials. If those third parties do not perform as contractually required, fail to satisfy legal or regulatory requirements, miss deadlines or terminate the relationship, our development programs could be delayed, more costly or unsuccessful, and we may never be able to seek or obtain regulatory approval for or commercialize our product candidates; ● Our rights to develop and commercialize our product candidates are subject, in large part, to the terms and conditions of licenses granted to us by others, such as Xencor, Inc. (“Xencor”). If we fail to comply with our obligations in the agreements under which we in-license or acquire development or commercialization rights to product candidates, or data from third parties, we could lose such rights that are important to our business; ● The operations of our suppliers, many of which are located outside of the U.S., including our current sole contract manufacturing organization (“CMO”) for drug substance and drug product, WuXi Biologics (Hong Kong) Limited (“WuXi Biologics”), which is located in China, are subject to additional risks that are beyond our control and that could harm our business, financial condition, results of operations and prospects; ● An active and liquid trading market for our common stock may not be sustained; and ● The market price of our common stock may be volatile, which could result in substantial losses for investors. If we are unable to adequately address these and other risks we face, our business, results of operations, financial condition and prospects may be harmed. NOTE REGARDING TRADEMARKS The Zenas BioPharma word mark, logo mark, and the “lightning bolt” design are trademarks of Zenas BioPharma, Inc. or its affiliated companies. We have, in certain cases, omitted the ® and ™ designations for these trademarks used in this Annual Report. Nevertheless, all rights to such trademarks are owned by Zenas BioPharma, Inc. Other trademarks referenced in this Annual Report are the property of their respective owners. ​ PART I Item 1. Business Overview We are a clinical stage global biopharmaceutical company committed to being a leader in the development and commercialization of transformative immunology-based therapies for patients in need. With the evolving understanding of the pathogenesis of autoimmune diseases, along with the expansion of promising immunology-based pharmacologic targets, we are building an immunology and inflammation (“I&I”) focused biopharmaceutical company. Our core business strategy combines disciplined product candidate acquisition with strategic deployment of internal expertise and effective use of external resources. We leverage our experienced executive management team and our established networks throughout the biopharmaceutical industry to identify, acquire and develop product candidates that we believe can provide superior clinical benefits to patients living with autoimmune diseases. 6 Table of Contents Our lead I&I product candidate, obexelimab, is a bifunctional monoclonal antibody designed to bind both CD19 and FcγRIIb, which are broadly present across B cell lineage, in order to inhibit the activity of cells that are implicated in many autoimmune diseases without depleting them. Based on existing clinical data generated to date, we believe that targeting B cell lineage via CD19 and FcγRIIb can inhibit B cells and has been shown to be well-tolerated. While anti-CD20 or other anti-CD19 targeting agents may effectively deplete B cells in systemic circulation, these agents do not fully impact B cells in relevant tissue, and the intermittent dosing regimens of these agents may not provide optimal benefits for all patients. In addition, anti-CD20 and other anti-CD19 targeting agents may cause prolonged depletion of circulating B cells for six months or longer, placing patients at higher risk of opportunistic infections and potentially reducing their ability to respond to, and receive full benefit from, vaccines. We believe obexelimab’s mechanism of action and chronic dosing regimen may broadly and effectively address the pathogenic role of B cell lineage in chronic autoimmune disease. Across five clinical trials, in which 198 subjects were dosed, obexelimab was well-tolerated and demonstrated clinical activity that we believe provides POC for obexelimab as a B cell inhibitor for the treatment of patients living with certain autoimmune diseases and, together with its mechanism of action, positions obexelimab to be a potentially differentiated B cell therapy for the treatment of such patients. We believe obexelimab holds the potential to provide meaningful clinical benefit for patients in multiple I&I indications. We are developing obexelimab as a potential I&I franchise for patients in several autoimmune diseases, representing substantial commercial opportunities, individually and in the aggregate. The first three indications we are pursuing include immunoglobulin G4-related disease (“IgG4-RD”) through an ongoing registration-directed Phase 3 trial which completed enrollment in November 2024 and relapsing multiple sclerosis (“RMS”) and systemic lupus erythematosus (“SLE”) through ongoing Phase 2, double-blind, randomized, placebo-controlled trials, each of which are currently enrolling. We estimate that each of these potential indications represent a multi-billion-dollar commercial opportunity in the U.S. alone. Beyond our lead product candidate, obexelimab, we have two other programs for the potential treatment of other I&I indications that we may continue to advance and ultimately develop and commercialize with partners. These consist of ZB002 (an anti-TNFα monoclonal antibody) and ZB004 (a CTLA-4-Ig fusion). We retain global rights for both assets. In addition, we hold the development and commercialization rights to one regional program, ZB001 (also known as VRDN-001, an insulin-like growth factor-1 receptor (“IGF-1R”) monoclonal antibody and related programs, which were recently exclusively sublicensed to a partner in greater China. To date, we have no product candidates approved for commercial sale in any country and have not generated any revenue from product sales.  7 Table of Contents Obexelimab Overview We are developing obexelimab for the treatment of several I&I diseases summarized in the pipeline figure below: Our lead product candidate, obexelimab, was engineered to mimic the natural antigen-antibody complex for the inhibition of B cells. By targeting CD19, obexelimab is designed to inhibit a broader B cell population, including plasmablasts and the subpopulation of CD19 expressing plasma cells, each of which produces high amounts of auto-antibodies. Co-engagement of CD19 and FcγRIIb by obexelimab has been shown to inhibit B cell activity, including antibody production, proliferation, cytokine secretion, B cell differentiation, and antigen presentation to T cells. In addition, obexelimab is designed to inhibit rather than destroy or deplete B cell lineage. Other anti-CD19 and CD20 targeting antibodies rely on antibody-dependent cell-mediated cytotoxicity (“ADCC”), complement-dependent cytotoxicity (“CDC”) and/or apoptosis or programmed cell death as a key component of their mechanism of action. ADCC, CDC and apoptosis activity are generally lower in disease-relevant tissue than the peripheral blood. In addition, in clinical practice other CD19 and CD20 targeted antibodies are typically dosed once every six months which has demonstrated efficacy, but may not provide sustained benefit in all patients due to variability in B cell depletion and recovery. The obexelimab mechanism of action and chronic dosing regimen may more broadly and effectively address the pathogenic role of B cell lineage in chronic autoimmune disease and has the potential to show greater clinical benefits, especially over a longer course of maintenance treatment. The inhibitory mechanism of obexelimab is believed to reduce the number of B cells in systemic circulation through margination of B cells to other tissues such as the lymph nodes and the spleen, rather than through depletion. The concept of margination is supported by preclinical and clinical data, where the substantial return of B cells in circulation of subjects receiving obexelimab was observed to occur as soon as six weeks after discontinuation of obexelimab administration, contrasted with the much longer period of B cell recovery observed with other CD19 and CD20 targeted depleting agents, which can take six months or longer following the last dose. The risks of prolonged B cell depletion include limitations on a patient’s ability to fight serious and opportunistic infections and on a patient’s ability to generate an adequate response to vaccines such as influenza, shingles, respiratory syncytial virus, and COVID-19. We believe the rapid return in B cell activity following the cessation or pause in obexelimab dosing could allow the patient’s immune system to more quickly return to baseline to protect against infections and allow a patient to receive vaccinations within as few as six weeks of his or her last dose, rather than potentially waiting six months or longer following treatment with an anti-CD19 or anti-CD20 targeted depleting therapy. Obexelimab has been evaluated in five completed clinical trials in which a total of 198 subjects have received obexelimab either as IV infusion at doses of up to 10 mg/kg (n=158) or as a SC injection at doses of up to 375 mg (n=40). Obexelimab was well-tolerated across these five trials and demonstrated PK, as well as clinical activity providing POC in multiple I&I 8 Table of Contents indications. Based on this clinical data, we believe obexelimab could have potential advantages over anti-CD19 and -CD20 targeted depleting agents. Other Programs Beyond our lead product candidate, obexelimab, we have two other programs for the potential treatment of other I&I indications that we may continue to advance and ultimately develop and commercialize with partners. ​ ​ ​ ​ ​ Product Candidate ​ Territory ​ Plan of Development ZB002 (anti-TNFα mAb) ​ Global ​ Phase 1b multiple ascending dose ("MAD") study in patients with RA ongoing ZB004 (CTLA-4-Ig fusion) ​ Global ​ Phase 1 single ascending dose ("SAD") study in healthy volunteers completed ​ ZB002, an anti-TNFα therapy designed to have an extended half-life as compared to existing anti-TNFα therapies. ZB002 is a recombinant human monoclonal antibody directed at human TNFα. ZB002 has an identical amino acid sequence to Humira (adalimumab) in the TNFα-binding region of the fragment variable domain; however, the Fc domain of ZB002 contains modifications designed to extend its half-life in vivo . If the results of our ongoing Phase 1b MAD study of ZB002 are favorable, we may seek to identify a partner to advance ZB002 in subsequent trials for potential use as a treatment for certain I&I diseases that can benefit from TNFα inhibition. We also own the global development and commercialization rights to ZB004, a CTLA-4-Ig fusion protein designed to have an extended half-life compared to approved CTLA-4-Ig fusion protein therapies, such as Orencia (abatacept) and Nulojix (belatacept). Similar to approved CTLA-4-Ig fusion protein therapies, the ZB004 mechanism of action is selective inhibition of T cell co-stimulation. The CTLA-4 motif binds to CD80 and CD86 on antigen-presenting cells, blocking the interaction of these receptors with CD28 on T lymphocytes, and thus inhibiting T cell co-stimulation. ZB004 contains two CTLA-4 extracellular domain substitutions designed to potentially produce greater CD80 and CD86 binding. Based on the ongoing analysis of data from the Phase 1 study, along with the known clinical efficacy of approved CTLA-4-Ig fusion protein therapies, we are seeking to advance the clinical development of ZB004 with a potential partner in indications where it could be uniquely positioned given its profile. Partnered Regional Programs We also have in-licensed the development and commercialization rights to ZB001 (also known as VRDN-001), an IGF-1R monoclonal antibody, and related programs from Viridian Therapeutics, Inc. (“Viridian”) in China, Hong Kong, Macau and Taiwan (collectively, “greater China”). On January 24, 2025, we entered into a license agreement (the “Zai License Agreement”) with Zai Lab (Hong Kong) Limited (“Zai”), under which we granted Zai an exclusive sublicense to develop and commercialize ZB001 and related programs in greater China. As partial consideration for the Zai License Agreement, we received an upfront fee of $10.0 million from Zai. In addition, we are eligible to receive up to $96.0 million upon the achievement of certain future development and commercial milestones and royalty percentage rates from the low to mid-single digits, net of pass-through obligations due to Viridian. In addition, on October 21, 2024, we entered into a novation agreement with Tenacia Biotechnology (Hong Kong) Co., Limited (“Tenacia”), under which we transferred to Tenacia our rights and obligations under our agreements with Dianthus Therapeutics Inc. (“Dianthus”) for ZB005 (the “Tenacia Agreement”). As partial consideration for the Tenacia Agreement, we received an upfront fee of $5.0 million from Tenacia. In addition, we are eligible to receive up to $86.0 million upon the achievement of certain future regulatory and commercial milestones. Our Management Team Our executive management team is comprised of seasoned executives and scientists with extensive experience in the biopharmaceutical industry, leading drug development and commercialization and executing successful business development strategies. Our company is led by Leon (Lonnie) O. Moulder, Jr., our Founder, Chief Executive Officer and Chairman, and the Managing Member of Tellus BioVentures, LLC, an early-stage life sciences investment fund. Prior to founding Zenas, Mr. Moulder co-founded TESARO, an oncology-focused biopharmaceutical company, serving as Chief Executive Officer and Director until its acquisition by GlaxoSmithKline. He previously served as President and Chief 9 Table of Contents Executive Officer of Abraxis BioScience and as Vice Chairman of Eisai Corporation of North America following Eisai’s acquisition of MGI PHARMA, where he served as President and Chief Executive Officer. Mr. Moulder is joined by our team of veteran biopharmaceutical executives, including Joseph Farmer, Jennifer Fox and Orlando Oliveira, who together with the leadership team, bring exceptional track records and experiences across the industry at companies such as TESARO, Inc., GlaxoSmithKline plc., Amgen Inc., Nuvation Bio Inc., Mirati Therapeutics, Inc., Cubist Pharmaceuticals, Inc. and other biopharmaceutical companies. Our leadership team has collectively been responsible for numerous INDs, and NDAs/BLAs and the associated commercial product launches of several successful pharmaceutical products. Our Strategy Our vision is to become a global leader in delivering transformative I&I therapeutics to patients in need. We intend to leverage the experience and capabilities of our executive management team and our established networks throughout the biopharmaceutical industry to identify, acquire, develop and, if approved, commercialize product candidates that we believe can offer enhanced efficacy, safety and/or convenience over existing therapies and thereby provide superior benefits to patients. We intend to achieve our goals by implementing the following strategies: ● Develop and commercialize our obexelimab franchise across multiple I&I indications . We are developing obexelimab as a potential I&I franchise for patients in several autoimmune diseases, representing substantial commercial opportunities individually and in the aggregate. The first three indications we are pursuing include IgG4-RD through an ongoing registration-directed Phase 3 trial; and RMS and SLE through ongoing Phase 2, double-blind, randomized, placebo-controlled trials. ● Build our operational capabilities to develop and potentially commercialize our products in key regions. With plans to advance our obexelimab franchise in multiple I&I indications, we intend to build the commercial capabilities necessary to achieve our goal of becoming a global development and commercial stage biopharma company. To that end, we have hired a Chief Commercial Officer and others within the commercial organization. ● Utilize our business development experience and expertise to continue to build a deep and balanced portfolio of products and product candidates. We acquired each of our product candidates through in-licensing from third parties. We intend to continue to utilize our business development strategy and expertise to build a balanced portfolio of new product candidates from preclinical through commercial assets. ● Leverage success with initial indications to expand into broader I&I opportunities. Our strategy for each product candidate is to initially pursue indications where the clinical translatability of the mechanism of action has been validated, where we believe we can independently and efficiently pursue clinical development and regulatory approval, and where we believe an attractive commercial opportunity exists. We also intend to pursue additional indications with larger patient populations where we believe our product candidates’ mechanisms may be relevant. ● Evaluate strategic collaborations as appropriate. We may in the future seek arrangements with other biopharmaceutical companies with strong and proven commercial capabilities for them to commercialize or co-commercialize our potential therapies in certain territories, if approved. In addition, for certain indications that may require larger clinical development programs, we may selectively seek to collaborate to help fund development. Obexelimab (CD19 x FcγRIIb bifunctional monoclonal antibody) Program We believe that our lead product candidate, obexelimab, has the potential to address key unmet needs in multiple I&I indications due to its mechanism of action and chronic dosing regimen that may broadly and effectively address the pathogenic role of B cell lineage through reversible inhibition of B cell activity without causing B cell depletion. Obexelimab is a bifunctional, non-depleting, humanized monoclonal antibody designed to bind CD19 and FcγRIIb to inhibit B-lineage cell activity. The antibody variable region of obexelimab has been engineered to bind CD19, whereas the constant region has been engineered to enhance affinity for the inhibitory FcγRIIb receptor. FcγRIIb is the only Fc receptor on B cells and serves as an antibody-sensing down-regulator of humoral immunity that is naturally engaged by 10 Table of Contents immune complexes. In addition, FcγRIIb regulates the activity of other B cell stimulators including interleukin-4, lipopolysaccharide and B cell activating factor (“BAFF”) that amplify BCR-driven proliferation and differentiation. By binding CD19 and FcγRIIb, obexelimab mimics the action of naturally occurring antigen-antibody complexes and inhibits B cell activity without depleting B cells in the lymph nodes or spleen. The mechanism of action of obexelimab shown below in Figure 1, involves co-engagement of CD19 and FcγRIIb, leading to inhibition of B cell activity, including antibody production, proliferation, cytokine secretion, B cell differentiation, and antigen presentation to T cells. Figure 1: Mechanism of Action of Obexelimab Through in vitro, in vivo and classical animal models of autoimmune disease, obexelimab’s binding to CD19 and FcγRIIb has been shown to enable the inhibition of B cell activity without depleting B cells. Preclinical and clinical studies have demonstrated that obexelimab rapidly achieved nearly 100% CD19 receptor occupancy, potently inhibiting B cell activity along with a decrease of approximately 50% in circulating B cell levels observed within one to two days. We believe the decrease in circulating B cell levels results from margination of B cells in lymphatic tissues, such as the lymph nodes and spleen, rather than depletion or elimination of the B cells. In contrast, anti-CD20 and other anti-CD19 B cell-targeting agents deplete B cells through B cell destruction. In clinical studies, we have observed substantial recovery of B cell levels in circulation following cessation of therapy with obexelimab within six weeks, as opposed to six months or longer that has been observed with B cell depleting agents. This rapid return in B cell activity following the cessation or pause in obexelimab dosing could allow the patient’s immune system to more quickly return to baseline to protect against infections and could allow a patient to receive vaccination within as few as six weeks of his or her last dose, rather than potentially waiting six months or more following treatment with an anti-CD19 or anti-CD20 targeted depleting therapy. Clinical Development Obexelimab has been evaluated in five completed clinical trials in which a total of 198 subjects have received obexelimab either as an IV infusion at doses of up to 10 mg/kg (n=158) or as a SC injection at doses up to 375 mg (n=40). Across these five trials obexelimab was well-tolerated and demonstrated clinical activity that we believe provides POC for obexelimab as a B cell inhibitor for the treatment of patients living with certain autoimmune diseases. Our current ongoing and planned future trials of obexelimab utilize a fixed 250 mg, dosed weekly as a self-administered SC injection. 11 Table of Contents Summary of Completed Clinical Trials for Obexelimab Study Description* Phase N Key Results Healthy Volunteers Study ​ Phase 1a ​ 48 ​ Demonstrated tolerability, PK and target engagement Rheumatoid Arthritis (“RA”) Trial ​ Phase 1b / 2a ​ 56 ​ Demonstrated POC by showing clinical activity in patients with RA IgG4-RD Trial ​ Phase 2 ​ 20 ​ Demonstrated POC in patients with IgG4-RD SLE Trial ​ Phase 2 ​ 104 ​ Demonstrated POC in patients with SLE by showing a reduction in disease relapse** SC & IV Formulation Bioavailability Study ​ Phase 1 ​ 50 ​ Established bridging of IV to SC formulation * These clinical studies were conducted by Xencor. The results of these studies are further described below. ** Primary endpoint did not achieve statistical significance. ● Study in Healthy Adult Volunteers: XmAb5871-01 was a Phase 1, randomized, blinded, placebo-controlled, SAD IV study of the safety, tolerability and PK of obexelimab in 48 healthy adult volunteers, with 36 receiving study drug, conducted in the United Kingdom. The primary objective of the study was to evaluate the safety and tolerability profile of a single-dose IV administration of obexelimab. The secondary objective was to characterize the single-dose PK and immunogenicity of obexelimab. The study demonstrated that obexelimab was well tolerated at all doses, including the highest dose of 10 mg/kg. Gastrointestinal (“GI”)-related TEAE (including nausea, vomiting, abdominal pain, abdominal discomfort, epigastric discomfort and diarrhea) were the most frequently reported (14/36, 38.9%). There were no SAEs reported. The study was not powered for statistical significance. ● Trial in Rheumatoid Arthritis: XmAb5871-02 was a Phase 1b/2a, randomized, placebo-controlled, double-blind, ascending multiple-IV dose trial of the safety, tolerability, PK, and PD of obexelimab in 56 patients with RA, with 40 receiving study drug. The trial was conducted at nine sites in four countries, including, Hungary, Poland, Czech Republic and Slovakia. The primary objective of the trial was to evaluate the safety and tolerability profile of multiple-dose, every 14-day, IV administration of obexelimab in patients with RA. The secondary objectives were to (i) characterize the PK and immunogenicity of multiple-dose, IV administered obexelimab in patients with RA and (ii) evaluate the effect of obexelimab on RA disease response. Complete CD19 receptor occupancy was seen at doses as low as 1 mg/kg from the first dose through the completion of dosing. The efficacy parameters evaluated in the trial showed an improvement trend in RA patients who received obexelimab when compared to patients who received placebo, although the trial was not powered to show significant changes. Patients who received obexelimab generally had improvement in ACR20, ACR50, ACR70, and DAS28-CRP Disease Activity when compared to patients who received placebo. In general, obexelimab was well tolerated, and the most common TEAEs were vomiting (7/40, 17.5%), headache (7/40, 17.5%), nausea (6/40, 15.0%), pyrexia (4/40, 10.0%), and arthralgia (4/40, 10.0%). Two subjects experienced infusion-related reactions (both at 10.0 mg/kg), one of which was considered an SAE. The other event, associated with the first infusion, was considered of moderate severity. In both cases, the infusion was terminated, and the patients recovered without sequelae. The trial was not powered for statistical significance. ● Trial in IgG4-RD: XmAb5871-03 was a Phase 2, open-label, single-arm IV, trial in 20 patients with IgG4-RD, including 15 patients dosed with 5 mg/kg of obexelimab, conducted in Boston, Massachusetts. The primary objective of the trial was to evaluate the effect of every-other-week IV administration of obexelimab on the IgG4-RD Responder Index (“RI”). The secondary objectives were to (i) evaluate the safety and tolerability of every-other-week IV administration of obexelimab in subjects with active IgG4-RD and (ii) evaluate the PK and immunogenicity of every-other-week IV administration of obexelimab in subjects with active IgG4-RD. In the 12 Table of Contents primary efficacy analysis, in patients receiving 5 mg/kg, the IgG4-related disease RI score at Day 169 had decreased by two or more points versus baseline in 12 (80%) patients, eight (67%) of whom had a score of zero (complete remission). Fourteen (93%) patients achieved an improvement on the RI of two or more points during at least one trial assessment at a median of 15 days (range 14 to 90) from treatment initiation. We believe these data demonstrated POC for obexelimab in IgG4-RD. In general, obexelimab was observed to be well tolerated in patients with IgG4-RD. The most common TEAEs were abdominal pain and nausea (4/20, 20.0%), vomiting (3/20, 15.0%), and diarrhea, chills, headache, nasal congestion, and upper respiratory tract infection (2/20, 10.0%). There was one case of pneumonia accounting for two SAEs (initial and recurrence due to non-compliance with therapy) in one patient and a second patient experienced one SAE (chronic inflammation demyelinating polyradiculoneuropathy in the setting of small lymphocytic lymphoma (pre-existing)). None of the SAEs were considered to be related to obexelimab. The trial was not powered for statistical significance. ● Trial in SLE: XmAb5871-04 was a Phase 2, double-blind, randomized, placebo-controlled, potential POC trial in 104 patients with SLE administered IV, with 52 receiving study drug. The trial was conducted at 23 sites in the U.S. The primary objective of the trial was to determine the ability of obexelimab to maintain SLE disease activity improvement achieved by a brief course of disease-suppressing intramuscular (“IM”) steroid therapy. The secondary objectives were to (i) evaluate time to loss of SLE disease activity improvement achieved by a brief course of disease-suppressing IM steroid therapy, (ii) evaluate the safety and tolerability of every-other-week IV administration of obexelimab in subjects with SLE and (iii) evaluate the PK and immunogenicity of every-other-week IV administration of obexelimab in subjects with SLE. Although the primary endpoint (the proportion of patients without loss of improvement in SLE disease activity) in the Efficacy Evaluable (“EE”) population was not achieved with statistical significance, the absolute treatment difference in the ITT population was 17.3% (40.4% obexelimab versus 23.1% placebo response, p = 0.06). The ITT analysis is relevant because all patients are considered in these analyses, whereas in the EE analysis there was a larger number of patients treated with placebo who discontinued treatment for reasons that removed them from the analysis. The difference in response rates between the obexelimab and placebo arms in this trial was similar to that observed in SLE registration-directed trials with other agents, although with different trial design and endpoints. Accordingly, we believe these data demonstrated POC for obexelimab in SLE. Obexelimab was generally well tolerated in patients with SLE. The most frequently occurring TEAEs were nausea (20/52, 39%), headache (12/52, 23%), vomiting (9/52, 17%), back pain and dizziness (8/52, 15%), flushing (7/52, 14%), and pain in extremity (6/52, 12%). There were eight SAEs in patients administered obexelimab, only one SAE (infusion-related reaction) of which was considered related to study drug. Adverse events led to the withdrawal of seven (13%) obexelimab-treated patients (most of which were infusion-related reactions) and two (4%) patients that were administered placebo. ● PK and Relative Bioavailability Study of SC versus IV Formulation: XmAb5871-05 was a Phase 1 PK and relative bioavailability study of obexelimab administered either intravenously or subcutaneously in 50 healthy volunteers, conducted in Glendale, California, USA. The primary objectives of the study were to (i) characterize and compare the PK and bioavailability of obexelimab administered either IV or SC and (ii) evaluate the safety and tolerability of obexelimab administered SC. The secondary objectives of the study were to (i) determine the immunogenicity of obexelimab administered SC and (ii) characterize and compare the PK of healthy subjects with healthy Japanese subjects. In this study, five separate cohorts were treated with five separate obexelimab dosing regimens: 125 mg SC, 250 mg SC, 375 mg SC, or 250 mg IV every two weeks for six weeks, or 125 mg SC every week for three weeks. The absolute bioavailability of obexelimab across all cohorts after the SC administration was observed to be 58.1% and 53.6% after the first and third doses, respectively. All of the SC doses were observed to be well tolerated in all subjects. In the SC cohorts, the only TEAE occurring in more than two subjects was injection site bruising, which occurred in less than 2% of injections, was considered mild and resolved within 24 hours. The incidence of GI TEAE attributed to SC administration of obexelimab was less than 3%. There were no SAEs reported. Accordingly, we believe that the PK, relative bioavailability, and tolerability demonstrated in this study support the continued clinical development of the SC formulation of obexelimab. Obexelimab has demonstrated clinical activity across multiple I&I indications. We are currently pursuing a registration-directed trial in patients with IgG4-RD and ongoing Phase 2, double-blind, randomized, placebo-controlled clinical trials of obexelimab in patients with RMS and SLE. Despite the promising results from the Phase 1b/2a trial of obexelimab in RA, we do not intend to develop obexelimab further in RA due to the competitive landscape in that disease. While we believe that the preliminary results from the SApHiAre Trial in patients with warm autoimmune hemolytic anemia 13 Table of Contents (“wAIHA”) patients established proof of mechanism through an increase in Hgb and a positive effect on other clinical markers, we have determined not to progress to a registration-directed trial of obexelimab for the wAIHA indication based on several factors, including the expected length and expense of a potential Phase 3 trial. Obexelimab for the Treatment of IgG4-RD We believe obexelimab’s differentiated mechanism of action as an inhibitor of B cell lineage supports its potential to play an important role in the treatment of IgG4-RD. The reported evidence for the role of B cells in the pathogenesis of IgG4-RD, the observed effects of B cell targeting agents in previous trials in IgG4-RD and the data from our Phase 2 IgG4-RD trial with obexelimab support the continued development of obexelimab in patients with IgG4-RD. In November 2024, we completed enrollment of in our INDIGO Trial, a global Phase 3 registration-directed, randomized, double-blind placebo-controlled trial of obexelimab delivered 250 mg subcutaneously weekly to evaluate the prevention of flares in patients with IgG4-RD. We expect to report topline data from our INDIGO Trial year end 2025 and, subject to the data, submit a biologics license application (“BLA”) in 2026. IgG4-RD Histology and Disease Background IgG4-RD is a chronic fibro-inflammatory condition that can affect virtually all organ systems, including the pancreas, biliary tract, salivary and lacrimal glands, lungs, and kidneys. Patients with IgG4-RD may present with a single organ involved but more frequently present with multiple organ involvement. As the disease progresses and patients experience new or worsening symptoms (i.e., flares), lesions develop in additional organs and the cellular inflammation characterizing early disease moves toward a more fibrotic stage, which can lead to major irreversible tissue damage and ultimately organ failure. The most common symptoms in patients with IgG4-RD and their relative frequency of presentation are highlighted below in Figure 2. IgG4-RD is a relatively recently described disease that incorporates groups of manifestations that were diagnosed as separate disease entities prior to 2003. We estimate that the currently diagnosed population of IgG4-RD patients in the U.S. is approximately 20,000, with what we believe to be comparable prevalence rates globally. The pathogenesis of IgG4-RD suggests that B cell-targeted therapies may provide therapeutic benefit. Several B cell subsets have recently been shown to be elevated in the peripheral blood of IgG4-RD patients. Moreover, plasmablasts have been shown to actively contribute to tissue fibrosis through multiple mechanisms, including production of pro-fibrotic molecules and stimulation of collagen production by fibroblasts. 14 Table of Contents Figure 2: IgG4-RD: A Chronic Fibro-inflammatory Disease Characterized by Flares Current Treatment and Unmet Need Despite the growing recognition of IgG4-RD and advances in the understanding of its pathophysiology, there are no approved therapies for the treatment of this disease and there remains high unmet medical need. There are few treatment options, which are often limited by co-morbidities common among patients with IgG4-RD, including diabetes, obesity and hypertension. The current standard of care is glucocorticoid treatment (“GCs”), however such treatment often results in various complications. Although GCs are initially effective in most patients, up to 60% of patients with IgG4-RD will relapse within 12 months of discontinuing GC treatment. IgG4-RD is a disease commonly marked by flares, which can lead to the accumulation of fibrosis, resulting in irreversible organ damage, often involving multiple organs, and past flares are often a strong indicator of future flares. Therefore, patients are in need of long-term maintenance treatment. However, maintenance therapy with GCs has not been shown to prevent recurrence of disease and can lead to significant toxicity and complications, including osteoporosis, hypertension, and diabetes, especially in elderly patients. In addition to GCs, the pathogenesis of IgG4-RD suggests that B cell-targeted therapies may provide therapeutic benefit. As a result, although not approved by any regulatory bodies to treat IgG4-RD, certain B cell depleting agents (e.g. rituximab) are occasionally used in such patients. However, B cell depleting agents are often associated with infections, including serious opportunistic infections, and can compromise a patient’s ability to mount a response to vaccinations. This was shown in a small pilot study of rituximab, a B cell-targeted therapy, in patients with IgG4-RD. We believe this is due to the fact that rituximab and other B cell depleting agents can cause prolonged depletion of B cells for six months or longer, which places patients at risk of opportunistic infections and potentially reduces response to vaccines. Summary of the Completed Phase 2 Trial of Obexelimab in IgG4-RD In August 2023, the results of the Phase 2, open-label, single-arm, trial of obexelimab for the treatment of patients with IgG4-RD were published in The Lancet Rheumatology. Twenty patients with active IgG4-RD, defined as an IgG4-RD RI score of three or more, were enrolled. Fifteen patients received obexelimab 5 mg/kg IV every two weeks for 24 weeks. 15 Table of Contents The protocol was later amended to also provide for the enrollment of an additional five patients who would receive a fixed dose of obexelimab of 90 mg IV or 180 mg IV every two weeks for 24 weeks. The pre-specified primary analysis of this study focused on the 15 patients enrolled at obexelimab 5 mg/kg. At baseline, the median IgG4-RD RI score was 12 (IQR 7-13). In the primary efficacy analysis, as shown in Figure 3 below, the median decrease in the IgG4-RD RI score was 11.5 points (IQR 7.5-14.5). The IgG4-RD RI score at day 169 had decreased by two or more points from baseline in 12 (80%) patients, eight (67%) of whom had a score of zero (complete remission). These patients included four (80%) of five patients who had achieved remission on previous therapies. Fourteen (93%) patients achieved an improvement on the RI of two or more points during at least one trial assessment at a median of 15 days (range 14 to 90) from treatment initiation. One (7%) patient did not achieve an improvement on the RI score of two or more points, and further evaluation found that this patient who failed to achieve at least a two point improvement on the RI scale had atypical disease activity in only the larynx. Twelve (80%) patients achieved a combined (secondary) endpoint of a decrease on the RI of two or more points at day 169, with no steroid use after day 57, and no disease flares. All primary responders had sustained responses through the end of the trial. The one (7%) patient who did not meet clinical response criteria had a RI score of two at baseline and a score of one before withdrawing from the trial after the Day 71 dose due to lack of efficacy (an IgG4-RD RI score reduction of less than two). Two responders also did not complete the trial: one discontinued after experiencing a disease relapse and one discontinued after an infusion-related hypersensitivity reaction during the fifth infusion. Thirteen (87%) patients experienced adverse events with the most common adverse event of GI infusion-related, including nausea, abdominal pain, and diarrhea. Figure 3: Rapid and Sustained IgG4-RD RI Responses from Phase 2 Trial Furthermore, as shown in Figure 4 below, circulating B cell counts decreased by approximately 60% throughout the treatment period. However, among seven patients with post-treatment follow-up data, four (57%) demonstrated recovery of circulating B cells to at least 75% of baseline within 42 days of the final obexelimab dose. Circulating plasmablasts also decreased quickly, by approximately 70 to 80%, and began returning following cessation of obexelimab. Obexelimab inhibited B cell receptor-linked signaling pathways but did not induce B cell depletion. Both reductions in circulating B cells without evidence of depletion during obexelimab treatment and their rapid rebound after treatment discontinuation suggest that obexelimab might lead to B cell sequestration (margination) in lymphoid organs or the bone marrow. After the first dose of obexelimab, CD19 receptor occupancy was nearly 100% for most patients and remained at or near complete occupancy until after the last dose of obexelimab at day 155. We believe these results are promising and support the continued development of obexelimab for the treatment of IgG4-RD and potentially other B cell-mediated I&I conditions. 16 Table of Contents Figure 4: Rapid Recovery of Systemic B Cells Upon Discontinuation Following enrollment of the first 15 patients treated at 5 mg/kg every other week, an additional five patients were enrolled in a separate cohort to explore a fixed dose regimen of obexelimab 90 mg IV every other week. All five patients achieved a decrease of two points or greater in the IgG4-RD RI at some time during the trial; however, three patients required an increased dose of obexelimab 180 mg IV every other week for disease flare, and two patients also received corticosteroids after Day 57. Peak serum concentration for patients who received 90 mg of obexelimab was approximately 25% and at 180 mg were approximately 50% of those patients who received 5 mg/kg. Safety Summary One patient experienced pneumonia accounting for two SAEs (initial and recurrence due to non-compliance with antibiotic therapy), and a second patient experienced one SAE (chronic inflammatory demyelinating polyradiculoneuropathy in the setting of small lymphocytic lymphoma (preexisting)). None of these events were considered by the investigator to be related to obexelimab. Certain patients also experienced mild to moderate IV infusion-related GI symptoms. The most common TEAEs were abdominal pain and nausea (4/20, 20.0%), vomiting (3/20, 15.0%), and diarrhea, chills, headache, nasal congestion and upper respiratory tract infection (2/20, 10.0%). INDIGO Trial—Our Ongoing Global Phase 3 Trial in IgG4-RD In November 2024, we completed enrollment of patients in our INDIGO Trial, a global Phase 3 registration-directed, double-blind, placebo-controlled trial to evaluate the safety and efficacy of SC obexelimab in patients with active IgG4-RD in a randomized controlled period followed by an optional open-label extension period. Approximately 190 patients were enrolled in the RCP and all patients from the RCP will be eligible for the OLE period. The trial is being conducted at approximately 100 sites in 20 countries. The RCP consists of a screening period (Day -28 to Day -1) and a 52-week treatment period, during which 250 mg of obexelimab or placebo will be administered as an SC injection every seven days. Following the 52-week RCP, eligible patients will have the opportunity to continue in an OLE period where all patients will receive obexelimab. 17 Table of Contents Figure 5: INDIGO Trial Schema To be considered eligible for the screening period, patients must have had a clinical diagnosis of IgG4-RD, met the 2019 ACR/EULAR classification criteria for IgG4-RD, as determined by an Adjudication Committee (“AC”), and had active IgG4-RD signs/symptoms (i.e., flare) that require, as assessed by the investigator, the initiation of GC therapy or an increase in background long-term GC therapy. All patients were required to receive three to six weeks of GC treatment at a dose of 20 to 60 mg/day prednisone equivalent prior to randomization. The required GC therapy could either have been newly initiated or an increase in long-term GC therapy (i.e., patient was previously on a dose of ≤ 10 mg/day prednisone equivalent). The exact dose and taper schedule during the screening period and prior to randomization are at the discretion of the investigator. However, on the day of randomization, patients must have had no disease activity and been at a dose of 20 mg/day prednisone equivalent. Patients were randomized 1:1 to receive obexelimab or placebo. The primary efficacy assessment was time to first IgG4-RD flare, as determined by the investigator and the AC. If the investigator suspected an IgG4-RD flare, based on reappearance of previous signs/symptoms or appearance of new signs/symptoms of IgG4-RD, organ-specific diagnostic assessments were conducted, including a physical examination, imaging and/or testing of biochemical parameters specific to the involved organ(s), to correlate symptoms and to document disease activity. The investigator then determined if an IgG4-RD flare occurred and whether the initiation of rescue therapy was required. The AC independently reviewed these diagnostic assessments to determine if, in their judgement, the signs/symptoms represent a flare. Patients who met the protocol-defined criteria for IgG4-RD flare, by both the investigator and the AC, were counted as treatment failures for the primary endpoint of time to first flare and the key secondary endpoint of proportion of patients who remain free of IgG4-RD flare (i.e., complete remission). Rescue therapy outside of permitted GC therapy would result in discontinuation from obexelimab or placebo treatment, as the case may be. The trial was designed with approximately 90% power to detect a hazard ratio of 0.376 using a one-sided log-rank test at a significance level equal to 0.025. Secondary endpoints include: 52-week flare rate, the proportion of patients achieving complete remission, use and quantity of rescue medication and the change in GC-associated toxicity as measured by the Glucocorticoid Toxicity Index (“GTI”). Patients who complete the RCP Week 52 visit and meet all OLE eligibility criteria will have the option to participate in the trial for up to an additional 116 weeks (104-week treatment period followed by a 12-week follow-up) in the OLE period. During the OLE, all patients will receive obexelimab once every seven days beginning on Day 1 of the OLE period, regardless of their treatment assignment during the RCP. The primary objectives for the OLE are to evaluate the safety and efficacy of obexelimab in patients with IgG4-RD. Obexelimab for the Treatment of MS We believe obexelimab’s differentiated mechanism of action as an inhibitor of B cell lineage supports its potential for the treatment of MS. The role of B cells in the pathogenesis of MS has been demonstrated through the successful clinical development, approval and clinical use of anti-CD20 B cell targeting therapies of other companies, including OCREVUS (ocrelizumab) and KESIMPTA (ofatumumab), which selectively deplete peripheral CD20-expressing B cells. B cells are thought to play a central role in MS pathology and its concomitant neurodegeneration via multiple mechanisms. In addition to antibody secretion by plasmablasts and plasma cells, B cell functions implicated in MS pathogenesis include antigen presentation to T cells and production of pro-inflammation cytokines. We believe this activity observed from B cells may contribute to both MS relapses as well as the underlying disease progression. In the third quarter of 2024, we initiated the MoonStone Trial, a Phase 2, multicenter, randomized, double-blind, placebo-controlled trial, to evaluate the efficacy and safety of obexelimab in patients with RMS. 18 Table of Contents MS Histology and Disease Background MS is the most common immune-mediated, chronic inflammatory demyelinating disease of the central nervous system (“CNS”), affecting over two million people worldwide including as many as 1,000,000 in the U.S., according to the National MS Society and the MS Foundation. We estimate a diagnosed prevalence of approximately 650,000 patients in the U.S. with MS. MS is characterized by numerous demyelinating lesions of the brain and spinal cord. The magnetic resonance imaging (“MRI”) hallmark of the disease are multiple areas of demyelination in the CNS. The clinical features of an MS attack depend on the areas of the brain or spinal cord involved, thus symptoms may include sensory and visual disturbances, motor, coordination impairment and spasticity, fatigue, pain, and cognitive deficits. Its peak onset is typically in adults between 20 – 40 years old. The most common course of MS is relapsing-remitting (“RRMS”), which affects as many as 85% of MS patients. Patients with RRMS experience episodes of neurological dysfunction followed by complete or incomplete recovery. Over time, the majority of RRMS patients develop disease progression, with or without relapses, referred to as secondary progressive MS (“SPMS”). Patients with RRMS and SPMS with relapses are typically referred to as having RMS. Lastly, 10 to 15% of patients present with a gradually progressive disease course from onset known as primary progressive MS (“PPMS”). Most patients initially diagnosed with RRMS experience two distinct clinical phases, the relapsing-remitting and progressive phases, each of which is reflected by a distinct pathological process. During the relapsing-remitting phase, inflammation drives disease activity while neurodegeneration, which is characterized by accumulating disability, is predominant in the progressive phase. However, underlying progression occurs in all forms of MS, and obexelimab’s unique mechanism of action has the potential to impact both the inflammation and neurodegeneration aspects of MS pathogenesis. Currently, the cause of MS remains unknown; however, both B and T cells play an important role in the pathogenesis of the disease, including inflammation and demyelination process. In addition to producing autoantibodies and inflammatory cytokines, B cells have an important function as antigen-presenting cells (“APCs”) involved in T cell activation. The APC function of B cells is thought to be an important reason for the beneficial effects of B cell therapies in MS. Chronic CNS inflammation in the MS lesion is maintained, in part, with activated pro-inflammatory macrophages, microglia and astrocytes at the rim of chronic active or slowly expanding MS lesions, which are the site of ongoing demyelination and neuronal damage. The continued expansion of chronic active lesions is believed to play a role in the pathogenesis of disease progression in MS. 19 Table of Contents Figure 6: Role of B and T Cells in Multiple Sclerosis The potential efficacy of obexelimab in the treatment of MS has been demonstrated preclinically in a prophylactic disease animal model. An obexelimab surrogate antibody (XENP8206) was evaluated versus a rituximab surrogate antibody and vehicle control in a preclinical experimental autoimmune encephalomyelitis (“EAE”) model. As shown in Figure 7 below, XENP8206 prevented disease incidence to a greater extent than the rituximab surrogate antibody and the activity of XENP8206 was not associated with B cell depletion. Figure 7: Suppression of Disease Activity in EAE Model Without B Cell Depletion ​ Current Treatment, Limitations and Remaining Unmet Need Despite various treatments available for MS patients, unmet clinical needs remain, including a lack of an effect on progression independent of relapse activity (“PIRA” or also known as “silent progression”), which has been observed even in patients with early RMS on highly effective therapies. Gadolinium enhancement is a sensitive technique for detecting active MS lesions and confirms the inflammatory activity of the disease. Monitoring the change in these MRI contrast enhancing lesions is routine and decreased MRI activity represents the earliest treatment effects in clinical trials. In many MS Phase 3 trials, including those of B cell therapies, reductions in inflammatory lesions, initially demonstrated in Phase 20 Table of Contents 2 POC trials utilizing MRI endpoints, were often accompanied by clinical improvements. The paramagnetic rim lesion may serve as another important emerging MRI marker of chronic neuroinflammation, with any modification observed in a clinical trial potentially indicating a change in disease progression. In the third quarter of 2024, we initiated a Phase 2 potential POC trial of obexelimab in RMS patients, utilizing various MRI detection techniques and biomarkers to assess its impact in both the acute and chronic aspects of the disease. To date, there are a number of therapies that have been approved for the treatment of MS, including injectable, oral and infused medications. Although MS is historically considered a T cell disease, blockade of B cell autoreactivity inhibits neuroinflammation through several pathways, including (i) preventing B cells from acting as antigen-presenting cells that activate autoreactive T cells, (ii) preventing B cells from releasing proinflammatory cytokines, (iii) preventing B cells from transforming into plasma cells that may produce myelin-directed autoantibodies, and (iv) preventing B cells from forming meningeal lymphoid follicles. Despite effective treatment for relapses, there remains a considerable proportion of patients who experience ongoing disease activity and/or accumulating progression of disability. Within 20 years of diagnosis, 30 – 60% of patients with RRMS convert to SPMS with relapse-independent disability progression resulting in severe limitations on quality of life. Despite currently approved therapies, there is an enduring need for additional safe and effective treatments that address the underlying progression seen in MS to potentially alter the course of disability. Our Global Phase 2 Trial in RMS Given the clinical activity observed with B cell depleting agents, we are currently enrolling patients in the MoonStone Trial, a global Phase 2 potential POC trial of obexelimab in RMS patients. We expect to enroll approximately 93 patients and to conduct the trial at multiple sites worldwide. The Phase 2 trial in RMS is a randomized, placebo-controlled trial in patients with relapsing active forms of MS in order to assess the safety and efficacy of a 250 mg weekly SC dose of obexelimab, utilizing various MRI detection techniques and biomarkers to assess its impact in both the active and chronic aspects of the disease. The primary objective of this trial is to assess the change from baseline in the cumulative number of new Gd-enhancing lesions identified on T1-weighted MRI over the course of three months. Upon completion of the three-month period, patients on placebo will receive obexelimab treatment for at least three months and patients initially randomized to obexelimab will continue on treatment. Important secondary endpoints include changes in various other MRI assessments (i.e., changes in T2-weighted lesions, changes in the number of new phase RIM lesions, number of T1 lesion conversions to phase RIM lesions, etc.). We expect to report data from the MoonStone Trial on the primary endpoint at 12 weeks in the third quarter of 2025. Obexelimab for the Treatment of SLE The crucial role of B cells in SLE pathogenesis is well recognized, from producing autoantibodies to abnormal regulation of immune responses. Moreover, SLE is an autoimmune disease characterized by B cell dysfunction, the production of autoantibodies toward cellular and nuclear components, and multiorgan damage caused by immune complex deposition and inflammation within affected tissues. Obexelimab has demonstrated clinical activity as a B cell-directed agent due to its inhibitory effect on B cell lineage via its binding to CD19 and FcγRIIb, and a prior Phase 2 double-blind, randomized trial we believe demonstrated POC in SLE. In the third quarter of 2024, we initiated the SunStone Trial, a Phase 2, multicenter, randomized, double-blind, placebo-controlled trial, to evaluate the efficacy and safety of obexelimab to reduce disease activity in patients with SLE. SLE Histology and Disease Background SLE, the most common form of lupus, is a complex, chronic autoimmune disease characterized most notably by unpredictable flares in joints, skin, kidneys and other vital organs that cause progressive organ damage. The prognosis of SLE varies from patient to patient, with alternating periods of active symptoms and remission throughout their lifetime. SLE ranges from a relatively benign disease to rapidly progressive and even fatal. Comorbidities, such as infections, malignancies, hypertension, lipid disorders and diabetes, increase the risk of disability and death in patients. SLE commonly affects the central nervous system, kidneys, gastrointestinal system, mucous membranes, heart, skin, hematologic system, musculoskeletal system and lungs. 21 Table of Contents Figure 8: SLE Disease Characteristics Increased B cell activity and survival mediated through BCR abnormalities is a classic feature of SLE. BCR signals are impacted by several regulatory surface proteins, including CD19 and FcγRIIb. Activation of FcγRIIb is known to effectively dampen BCR signaling and decrease B cell responses to activating signals, which may play a pivotal role in suppressing a patient’s own immune system from attacking cells. In addition, data in both murine lupus models and human lupus studies provide a rationale for targeting CD19 and FcγRIIb as a treatment for SLE. Current Treatment, Limitations and Remaining Unmet Need According to the Lupus Foundation of America, at least 1.5 million Americans are afflicted by lupus and more than 16,000 new cases are reported annually. It is estimated that five million people throughout the world suffer from some form of lupus, of which approximately 70% suffer from the most common form, SLE. Lupus affects primarily women of childbearing age (15 to 44 years). However, men, children and teenagers can also develop lupus. We estimate a diagnosed prevalence of approximately 245,000 patients in the U.S. having lupus, with approximately 150,000 having SLE. The current treatment strategy for SLE is based on treating the affected organ(s) and focuses on achieving a defined state of remission or low disease activity. Targeting B and plasma cells may have positive results in the overall treatment of SLE because of the role autoantibodies play in the pathogenesis of the disease. 22 Table of Contents Current treatments include non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, hydroxychloroquine, Benlysta (belimumab) (FDA approved for SLE in 2011), and Saphnelo (anifrolumab) (FDA approved for SLE in 2021). These limited FDA approved options are modestly effective with improvement in combination with standard therapy versus standard therapy alone in Phase 3 trials of nine to seventeen percentage points. We believe there is an opportunity to identify a clinically-validated biomarker to guide the selection or optimal administration of treatments. Summary of Obexelimab—Phase 2 Trial in Patients with SLE Study XmAb5871-04 was a Phase 2, double-blind, randomized, placebo-controlled trial to evaluate the ability of obexelimab to maintain SLE disease activity improvement in patients after brief treatment of active disease with corticosteroids. Patients were randomized 1:1 to receive intravenous obexelimab (5 mg/kg) or matching placebo every two weeks for 16 doses or until loss of improvement (“LOI”). LOI was defined by either a 4-point increase in the hybrid Systemic Lupus Erythematosus Disease Activity Index (“hSLEDAI”) score or at least one British Isles Lupus Assessment Group (“BILAG”) A or B score rated “new” or “worse”. One hundred and four patients were randomized, with 52 assigned to obexelimab treatment and 52 to placebo. Patients completing the trial included 28 (53.8%) receiving obexelimab and 17 (32.7%) receiving placebo. Median months of treatment was 6.9 (range 0 – 7.4) with obexelimab and 3.6 (range 0 – 7) with placebo. The primary endpoint was assessed as the proportion of patients reaching week 32 without LOI, using an EE population, defined as patients who completed the trial or withdrew for flare or treatment-related toxicity. Twenty-one out of 50 (42.0%) obexelimab-treated patients versus 12 out of 42 (28.6%) placebo-treated patients achieved the primary endpoint. Although the primary endpoint was not achieved with statistical significance (p = 0.183), the ITT population revealed a larger absolute treatment difference of 17.3% (40.4% versus 23.1%, p=0.06) in the obexelimab-treated group versus the placebo-treated group. The ITT analysis is relevant since all patients are considered in this analysis, whereas in the EE analysis a larger number of placebo-treated patients than obexelimab-treated patients discontinued treatment for reasons that removed them from the analysis (10 patients versus 2 patients). Furthermore, the placebo response rate (28.6% in the EE analysis and 23.1% in the ITT analysis) was higher than the 10% rate which was assumed in the statistical assumptions for the trial. Nevertheless, the difference in response rates between the obexelimab and placebo arms in this trial was similar to that observed in SLE registration-directed trials with other agents, although with different trial design and endpoints. Further, there was an association between obexelimab concentration and time to LOI. PK analysis revealed that quartiles of patients with progressively higher drug concentration had progressively longer time to LOI. In the EE analysis, patients in Ctrough quartiles three and four exhibited a larger absolute LOI treatment difference of 35% in the obexelimab-treated group versus the placebo-treated group. Accordingly, we believe these data demonstrated POC for obexelimab in SLE. Fourteen (26.9%) patients that received obexelimab and 25 (48.1%) patients that received placebo withdrew for LOI. Adverse events led to the withdrawal of seven (13%) obexelimab-treated patients (most of which were infusion-related reactions) and two (4%) patients that were administered placebo. Withdrawal for other reasons occurred in three patients that were administered obexelimab and eight that were administered placebo. There was no increase in the proportion of patients with infection in obexelimab as compared to placebo treated groups. The most frequently occurring TEAEs in patients who received obexelimab administered IV were nausea (20/52, 39%), headache (12/52, 23%), vomiting (9/52, 17%), back pain and dizziness (8/52, 15%), flushing (7/52, 14%) and pain in extremity (6/52, 12%). Biomarker analysis identified baseline gene expression profiles associated with increased response to obexelimab. Patients with adequate baseline RNA samples (71 in total) were assigned into one of seven clusters (immunophenotypes) as defined by Guthridge et al. 2020 using the Oklahoma Lupus Cohort. Patients in gene expression clusters three and six exhibited greater prolongation of time-to-flare with obexelimab, whereas in the other clusters obexelimab was not associated with a prolongation in time-to-flare. Patients in gene expression clusters three and six exhibited a larger absolute treatment difference in LOI of 52% in the obexelimab-treated group versus the placebo-treated group. There was a relatively small difference in time-to-flare between patients treated with placebo in clusters three and six compared with patients treated with placebo in the other clusters, suggesting that clusters three and six had higher predictive than prognostic value. Clusters three and six represent 38% of the population tested, which is similar to the 31% of cluster three and six patients in the original Oklahoma cohort. These clusters include patients of African and European descent and share increased expression of B cell pathways and low expression of inflammation pathways. These responsive immunophenotype 23 Table of Contents subgroups are thus consistent with the drug’s mechanism of action, inhibition of B cell, plasmablasts, and plasma cell activity, an impact that was observed in patients treated with obexelimab. We believe the obexelimab efficacy data in the overall trial population and the increased response in biomarker-defined subpopulations, coupled with the safety data obtained to date, provide support for further clinical trials and the use of a SC obexelimab formulation in patients with SLE. Our Global Phase 2 Trial in Patients with SLE We are currently enrolling patients in the SunStone Trial, a global Phase 2, multicenter, randomized, double-blind, placebo-controlled trial to evaluate the efficacy and safety of obexelimab when used to reduce disease activity in patients with SLE. We expect to enroll approximately 190 patients and to conduct the trial at multiple sites worldwide. We expect to complete enrollment of the SunStone Trial in 2025 and report data on the primary endpoint at 24 weeks in the first half of 2026. To be eligible for the trial, patients enrolled must have active SLE at screening, as defined by BILAG 2004 and hSLEDAI. Patients will be randomized 1:1 to obexelimab 250 mg or placebo SC injection every seven days over 24 weeks. The primary endpoint is the percentage of responders, defined by BILAG-based Composite Lupus Assessment, with a reduction of SLE disease activity at week 24. Biomarker analysis is planned to be conducted in all patients. This includes baseline RNA expression profiles to immunophenotype patients and evaluation of their differential responses to treatment. Additional biomarker assessments include serum cytokines and chemokines, SLE disease markers (complement C3/ C4, anti-dsDNA), and immune cell subsets (B cells, plasma cells, etc.). Obexelimab for the Treatment of wAIHA – SApHiAre Trial In December 2024, we announced preliminary results from patients in the open-label SRP of the Phase 2 portion of our SApHiAre Trial, a global study of obexelimab in patients with wAIHA. The primary objectives of the SRP are to provide preliminary safety, tolerability, PK/PD and efficacy data of obexelimab in patients with wAIHA. Patients were given 250 mg obexelimab weekly through subcutaneous administration for 24 weeks. The primary efficacy endpoint in the SRP is proportion of patients with a hemoglobin (“Hgb”) ≥ 10 g/dL and ≥ 2 g/dL increase from baseline on or after Week 8, with no use of blood transfusion or GC rescue therapy prior to attaining response. ​ As of the cut-off date, nine patients had been enrolled in the SRP over an approximately one-year period, including eight patients with primary wAIHA and one patient with secondary wAIHA due to autoimmune disease. One patient had not reached week four by the cut-off date and was not included in the analysis. Five of eight patients achieved an increase of >1 g/dL of Hgb from baseline during weeks 8-24 without influence of concomitant medications. Additionally, a Hgb increase of ≥ 2 g/dL measured from Hgb nadir to peak was observed in five of eight patients. LDH and total bilirubin levels decreased overall during weeks 8-24. No patients received transfusions. Obexelimab was well tolerated in patients with wAIHA with a safety profile similar to that observed in earlier studies. ​ While we believe that the preliminary results from the SApHiAre Trial established proof of mechanism through an increase in Hgb and a positive effect on other clinical markers, we have determined not to progress to a registration-directed trial of obexelimab for the wAIHA indication based on several factors, including the expected length and expense of potential Phase 3 trial. ​ Safety Profile of Obexelimab In the completed studies, 198 subjects have received obexelimab, 158 subjects as an IV infusion at doses of up to 10 mg/kg and 40 subjects as a SC injection of up to 375 mg. The majority of TEAEs in the studies using obexelimab were mild or moderate. The clinically important identified risk of obexelimab, defined by serious and related events observed in obexelimab treated subjects, included unanticipated infusion related reactions which have not been observed for the subcutaneous injection of obexelimab. The clinically non-important identified risks of obexelimab, defined as non-serious and related events, included intravenous infusion related GI events and injection site reactions via the SC administration. The injection 24 Table of Contents site reactions were of minimal clinical impact, non-serious, did not lead to study drug discontinuation, and are anticipated to occur in less than 2% of injections. The IV infusion related GI events were non-serious and were not observed with SC injection. Serious Adverse Events The only SAEs considered by the investigator to be related to obexelimab or placebo across the five clinical studies completed to date were: two IV infusion related reactions, one in each of two obexelimab treated patients, one venous thrombosis in an obexelimab treated patient, one herpes zoster in a placebo treated patient and a post herpetic neuralgia in a placebo treated patient. Anti-Drug Antibodies The development of anti-drug antibodies (“ADA”) has been observed in all studies; however, the ADA response did not have an apparent effect on PK or safety parameters (i.e., accelerated clearance), with the possible exception of one subject (in the first in human (“FIH”) study) and the three subjects with hypersensitivity reactions mentioned above. Safety Summary of Previously Completed Clinical Studies Study XmAb5871-01 Overall, doses of up to and including 10 mg/kg obexelimab were well tolerated by healthy male subjects. GI-related TEAEs (including nausea, vomiting, abdominal pain, abdominal discomfort, epigastric discomfort and diarrhea) were the most frequently reported (14/36, 38.9%). Eight subjects (8/36, 22.2%) who had received 0.2 to 10 mg/kg obexelimab had their IV infusion temporarily interrupted as a result of the GI-related symptoms. In all cases, symptoms leading to infusion interruption were transient and subjects were able to continue the infusion after a short break without recurrence of symptoms. Symptom resolution did not require the use of concomitant medications. No infusion-related reactions or hypersensitivity reactions were observed. There were no SAEs reported. No subject was withdrawn and none self-withdrew. There was no consistent dose-response relationship with the incidence of TEAEs and no dose-limiting toxicities were observed. Study XmAb5871-02 Among the 40 patients who received obexelimab, the most common TEAEs were vomiting (7/40, 17.5%), headache (7/40, 17.5%), nausea (6/40, 15.0%), pyrexia (4/40, 10.0%), and arthralgia (4/40, 10.0%). As in the FIH study in healthy male volunteers (Study XmAb5871-01), gastrointestinal-related TEAEs (nausea, vomiting, diarrhea) were mostly mild to moderate, resolved with interruption of infusion and did not reoccur with reinitiation of infusion. In general, multiple doses of up to 10 mg/kg obexelimab were well tolerated in patients with RA. Two subjects experienced infusion-related reactions (both at 10.0 mg/kg), one of which was considered an SAE. The other event, associated with the first infusion, was considered of moderate severity. In both cases, the infusion was terminated, and the patients recovered without sequelae. The nature and severity of these infusion reactions were consistent with those reported for other monoclonal antibody therapies. Study XmAb5871-03 In general, obexelimab was well tolerated in patients with IgG4-RD. The most common TEAEs were abdominal pain and nausea (4/20, 20%), vomiting (3/20, 15%), and diarrhea, chills, headache, nasal congestion, and upper respiratory tract infection (2/20, 10%). Four patients (4/20, 20%) had first dose GI symptoms of nausea, vomiting, and/or diarrhea as described previously with IV infusions. The symptoms were relieved by interrupting the infusion for a short period of time. There was one infusion-related hypersensitivity reaction that was associated with the presence of ADA, that was treated with symptomatic medications and that resolved after obexelimab was stopped. This patient recovered fully and discontinued the trial. There was one case of pneumonia accounting for two SAEs (initial and recurrence due to non-compliance with therapy) in one patient and a second patient experienced one SAE (chronic inflammation demyelinating 25 Table of Contents polyradiculoneuropathy in the setting of small lymphocytic lymphoma (pre-existing)). None of the SAEs were considered to be related to obexelimab. Study XmAb5871-04 Obexelimab was generally well tolerated in patients with SLE. The most frequently occurring TEAEs were nausea (20/52, 39%), headache (12/52, 23%), vomiting (9/52, 17%), back pain and dizziness (8/52, 15%), flushing (7/52, 14%), and pain in extremity (6/52, 12%). The majority of these events were mild and resolved. There were 8 SAEs in patients administered obexelimab, only one (infusion-related reaction) of which was considered related to study drug. Fourteen (14/52, 26.9%) patients that received obexelimab and 25 (48.1%) patients that received placebo withdrew for LOI. Adverse events led to the withdrawal of seven (7/52, 13%) obexelimab-treated patients (most of which were infusion-related reactions) and two (4%) patients that were administered placebo. Withdrawal for other reasons occurred in three patients that were administered obexelimab and eight that were administered placebo. Study XmAb5871-05 Overall, the SC administration of obexelimab was well tolerated. The most common TEAEs across all SC dose regimens were headache and injection site reaction (3/40, 8%). The incidence of injections with injection site erythema, induration and/or pain as a total out of all injections was 4/207 (total), or 1.9% of injections. The symptoms involved only one of the possible two or three sites injected on that day, were mild, and resolved within 24 hours. Dosage and Administration for Obexelimab Obexelimab has been evaluated in five completed clinical trials in which a total of 198 subjects have received obexelimab either as an IV infusion at doses of up to 10 mg/kg (n=158) or as a SC injection at does up to 375 mg (n=40). We believe these trials have demonstrated obexelimab’s PK/PD and tolerability profile. Our current ongoing and planned trials of obexelimab utilize or will utilize a fixed 250 mg self-administered SC injection dosed weekly. This dosing regimen is supported by the totality of existing clinical efficacy and safety data, PK/PD modeling, and nonclinical data. The 250 mg weekly SC dose is designed to maximize the potential for efficacy by providing maximum PD target engagement, comparable exposure and, importantly, a higher Ctrough when compared with the 5 mg/kg IV every two weeks dosing regimen, which demonstrated clinical activity in the IgG4-RD and SLE Phase 2 trials of obexelimab. In addition, the 250 mg weekly SC dose was designed to maintain a lower Cmax than the 5 mg/kg IV every two weeks dosing regimen to provide sufficient safety margins and an acceptable tolerability profile based on both clinical and nonclinical study data of obexelimab. Preclinical Characterization In vitro studies demonstrated that obexelimab has a high affinity for human CD19 and human FcγRIIb. The half-maximal effective concentration (“EC50”) of binding of obexelimab to a human CD19 expressing cell line is 0.3 nM, and the EC50 of binding of obexelimab to human primary B cells is 1.4 nM. The binding affinity of obexelimab for human FcγRIIb (8 nM) has been increased approximately 230-fold relative to human native IgG1 as a result of Fc engineering. In vitro , co-engagement of CD19 and FcγRIIb by obexelimab results in the inhibition of calcium mobilization upon stimulation of B cells from normal volunteers as well as in RA and SLE patients. In vivo , obexelimab demonstrated inhibition of an induced human B cell response to immunization with tetanus toxoid in severe combined immunodeficient mice engrafted with human peripheral blood mononuclear cells. In addition, obexelimab demonstrated disease improvement in several animal models of disease, including collagen-induced arthritis, AIHA and MS. Obexelimab has shown no antibody-dependent cellular cytotoxicity mediated B cell depletion in vitro, nor has there been any significant obexelimab-mediated IL-6 or TNF-α cytokine release. 26 Table of Contents Other Programs Beyond our lead product candidate, obexelimab, we have two other programs for the potential treatment of other I&I indications that we may continue to advance and ultimately commercialize with partners. These consist of ZB002 (an anti-TNFα monoclonal antibody) and ZB004 (a CTLA-4-Ig fusion). We retain global rights for both assets. ZB002 Program (anti-tumor necrosis alpha monoclonal antibody) ZB002 is a monoclonal antibody inhibitor of TNFα designed to have an extended half-life as compared to existing anti-TNFα therapies. ZB002 is identical to adalimumab in the TNFα-binding region of the fragment variable domain, but the Fc domain contains modifications to extend ZB002’s half-life in vivo (Xencor’s Xtend technology). Our Phase 1 SAD study demonstrated a half-life of approximately 55 days for ZB002, which we believe may allow for dosing once every four to eight weeks. In the second quarter of 2024, we initiated a Phase 1b MAD study of ZB002 in patients with rheumatoid arthritis. A head-to-head preclinical study in mice demonstrated ZB002’s extended (≥ 2-fold longer) half-life over adalimumab. If the results of our ongoing Phase 1b MAD study of ZB002 are favorable, we may seek to identify a partner to advance ZB002 in subsequent trials for potential use as a treatment for certain I&I diseases that can benefit from TNFα inhibition. Anti-TNFα Background and Mechanism of Action TNFα is a potent inflammatory cytokine, produced primarily by activated monocytes, macrophages and T cells, as a cell surface protein. After being activated, TNFα is released and binds to receptors on TNFα-responsive cells to enhance the inflammation and immune response to environmental stimuli such as foreign antigens. Elevated expression of TNFα has been linked to a number of I&I diseases, and inhibition of TNFα signaling has been validated as a therapeutic approach to treat several diseases. The FDA and other comparable foreign regulatory agencies have approved five anti-TNFα therapies to treat diseases, including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn’s disease, psoriasis, ulcerative colitis, hidradenitis suppurativa, and uveitis. Among those approved therapies are Remicade (infliximab), Simponi (golimumab) and Humira (adalimumab), monoclonal antibodies that target TNFα for inhibition. Summary of Clinical Trials We conducted a Phase 1 SAD study designed to evaluate the safety, tolerability, PK and PD profiles of ZB002 in healthy volunteers. We enrolled 48 healthy volunteers across six cohorts of varying dose levels, ranging from 20 mg to 240 mg, for the study. Eight healthy volunteers were randomized 3:1 to ZB002 or placebo, per cohort. There was one SAE of peri-anal abscess. Our Phase 1 SAD study demonstrated a half-life of approximately 55 days for ZB002, which we believe may allow for dosing once every four to eight weeks. In the second quarter of 2024, we initiated a Phase 1b MAD study of ZB002 in patients with rheumatoid arthritis. If the results of our ongoing Phase 1b MAD study of ZB002 are favorable, we may seek to identify a partner to advance ZB002 in subsequent trials and ultimately, if approved, commercialize ZB002 for potential use as a treatment for certain I&I diseases that can benefit from TNFα inhibition. Preclinical Characterization ZB002 has similar pharmacological characteristics to adalimumab, including TNFα binding and inhibition. The EC50 for in vitro inhibition of TNFα signaling is roughly equivalent (18.17 ng/mL for ZB002 and 14.25 ng/mL for adalimumab), and ZB002 and adalimumab inhibited TNFα-induced lethality in in vivo mouse models at similar rates. However, ZB002 has a higher fragment crystallizable receptor (“FcRn”) binding affinity (KD = 6.54 ×10 −8 M) compared to adalimumab (KD = 1.88 ×10 −6 M), which is designed to extend ZB002’s in vivo half-life. In the human neonatal FcRn expressed transgenic mice, the PK profile of ZB002 was found to be similar to that of adalimumab with the exception of an extended (≥ 2-fold longer) half-life (t1/2 = 9.9 hours and 4.1 hours for ZB002 and adalimumab, respectively). The subcutaneous bioavailability of ZB002 was 62.4% to 106.0% in cynomolgus monkeys, depending on the dose. Weekly subcutaneous administration of ZB002 for 13 weeks in cynomolgus monkeys demonstrated no adverse safety findings at any dose tested up to 200 mg/kg, providing an adequate therapeutic window for assessment in humans. 27 Table of Contents ZB004 Program (CTLA-4-IG fusion) ZB004 is a CTLA-4-Ig fusion protein designed to have an extended half-life versus existing CTLA-4-Ig fusion protein therapies. Based on the results from our ongoing Phase 1 study, we plan to evaluate the path forward for the development of ZB004 in the treatment of I&I indications. CTLA-4-Ig Background and Mechanism of Action ZB004 is comprised of two CTLA-4 extracellular domain substitutions and an IgG Fc region containing substitutions (Xencor’s Xtend technology). This design allows for increased binding affinity to human CD80 and CD86 and FcRn. Its mechanism of action is selective inhibition of T cell co-stimulation by binding to CD80 and CD86 receptors, which blocks their interaction with CD28 on T cells. In rheumatoid arthritis, T cells contribute to lymphoid organogenesis in the inflamed joint and neoangiogenesis, stimulate synoviocyte proliferation, and support the development of osteoclasts. CTLA-4, a protein expressed on the surface of CD4+ and CD8+ T cells, is an inhibitory receptor with high homology to the costimulatory receptor CD28. It acts as a negative regulator of CD28-mediated activation of CD4+ and CD8+ T cells. CTLA-4-Ig fusion proteins disrupt binding of CD28 with ligand B7 molecules, CD80 and CD86, expressed on antigen-presenting cells. Inhibition of this signaling pathway results in a suppression of T cell effector function and is clinically validated by the regulatory approval of two CTLA-4-Ig therapeutics in several I&I diseases: Orencia (abatacept) and Nulojix (belatacept). Clinical Development We conducted a Phase 1 SAD study designed to evaluate the safety, tolerability, PK immunogenicity and PD profiles of ZB004 in healthy volunteers. Our Phase 1 SAD study enrolled 40 healthy volunteers across five cohorts of varying dose levels, ranging from 3 mg to 200 mg, with eight healthy volunteers randomized 3:1 to ZB004 or placebo, per cohort. Our Phase 1 SAD study demonstrated a half-life of approximately 17.4 days at the highest dose level of 200 mg, where CD86 receptor occupancy reached a maximum peak value of 81%, overcoming the effect of target mediated drug disposition. There were no SAEs reported. Preclinical Characterization ZB004 has been engineered to increase its affinity to human CD80 and CD86 by approximately six-fold compared to abatacept. ZB004 also binds with higher affinity to human FcRn which is expected to extend ZB004 half-life in vivo . ZB004 has shown potency by inhibiting T cell activity and cytokine release. In an in vitro functional inhibition assay of T cell activity, the mean half-maximal inhibitory concentration (“IC50”) value was 0.334 µg/mL for ZB004 (2 donors) and > 50 µg/mL for abatacept. When the inhibition of inflammation cytokine release was assessed, the IC50 values for interleukin 2 (IL-2) secretion driven by ZB004 or abatacept were < 0.003 µg/mL and 0.152 µg/mL, respectively. The IC50 values for interferon gamma secretion driven by ZB004 and abatacept were 0.0054 µg/mL and > 50 µg/mL, respectively. ZB004 has shown prophylactic efficacy in a collagen-induced arthritis disease model. ZB004 was well tolerated in toxicology studies up to 13 weeks via subcutaneous administration in cynomolgus monkeys and rats, providing an adequate therapeutic window for assessment in humans. In addition, ZB004 has a PK profile in animals with a dose-disproportional increase in exposure. The terminal half-life parameter of ZB004 was determined at least 1.39-fold longer than that of abatacept in cynomolgus monkeys. The subcutaneous bioavailability of ZB004 was 45.4% to 72.5% for rats and 73.4% to 79.9% for cynomolgus monkeys, depending upon the doses. Partnered Regional Programs We license ZB001, an anti-IGF-1R monoclonal antibody, and related programs, from Viridian. For these assets we hold the development and commercialization rights in greater China and recently sublicensed these rights to Zai. ZB001 is a monoclonal antibody that binds to, and is designed to act as a full antagonist of, IGF-1 receptor. This mechanism of action has been clinically and commercially validated by the only FDA product approved for the treatment of thyroid eye disease (“TED”), Tepezza (teprotumumab). TED is a debilitating condition that significantly impacts quality of life 28 Table of Contents and can cause proptosis, double vision and vision loss. In October 2020, we entered into an exclusive license with Viridian, to develop, manufacture, and commercialize certain IGF-1R directed antibody products, including ZB001, for non-oncology indications in greater China. Pursuant to our agreement with Viridian, we are obligated to reimburse Viridian for certain CMC and development expenses, and pay Viridian upon achievement of development milestones and royalties on net sales. With our sublicense to Zai, Zai will pay for the reimbursement obligations and provide us with specified milestones and royalties. For more information on our agreement with Viridian, see the section titled “Certain Relationships and Related Party Transactions—Director Affiliations—Agreements with Viridian Therapeutics Inc.” In April 2023, we completed a Phase 1 SAD study in China in healthy volunteers showing ZB001 was well tolerated when administered in doses up to 20 mg/kg. In April 2024, we completed the last patient visit in the Phase 1 MAD study of ZB001 in Chinese patients with active TED. Preliminary data showed significant and rapid improvement in both signs and symptoms after 4 infusions of ZB001 in both 2 dose cohorts of 3mg/kg and 10mg/kg. All AEs were mild or moderate in severity and no SAEs were reported. On January 24, 2025, we entered into the Zai License Agreement with Zai, under which we granted Zai an exclusive sublicense to develop and commercialize ZB001 and related programs in greater China. As partial consideration for the Zai License Agreement, we received an upfront fee of $10.0 million from Zai. In addition, we are eligible to receive up to $96.0 million upon the achievement of certain future development and commercial milestones and royalty percentage rates from the low to mid-single digits, net of pass-through obligations due to Viridian. In addition, on October 21, 2024, we entered into the Tenacia Agreement, under which we transferred to Tenacia our rights and obligations under our agreements with Dianthus for ZB005. As partial consideration for the Tenacia Agreement, we received an upfront fee of $5.0 million from Tenacia. In addition, we are eligible to receive up to $86.0 million upon the achievement of certain future regulatory and commercial milestones. License Agreements License Agreements with Xencor 2020 Xencor Agreement In September 2020, we entered into a license agreement (the “2020 Xencor Agreement”) with Xencor, to obtain (i) an exclusive, royalty-bearing, sublicensable worldwide license under certain patent rights controlled by Xencor and (ii) a non-exclusive payment bearing license under certain know-how controlled by Xencor to research, develop, manufacture, market and sell three antibody product candidates (the “2020 Licensed Assets”), including ZB002 and ZB004. We subsequently relinquished rights to the third product candidate back to Xencor and that asset is no longer a 2020 Licensed Asset. Xencor obtained the rights to some of the intellectual property licensed to us pursuant to license agreements between Xencor and a third party (each such agreement, an “Upstream License Agreement”). As such, the 2020 Xencor Agreement provides that the parties agree that some of the licenses granted by Xencor to us constitute sublicenses under the Upstream License Agreements and are subject, and subordinate, to the terms and conditions of the Upstream License Agreements. As consideration for the 2020 Xencor Agreement, we issued Xencor a 15% equity interest in Zenas. The 2020 Xencor Agreement became effective in November 2020, upon Zenas’ issuance of 5,041,542 shares of its Series A Preferred Stock with a fair value of $16.1 million to Xencor as initial consideration. Under the 2020 Xencor Agreement, we are obligated to use commercially reasonable efforts to conduct all future preclinical, clinical and regulatory activities necessary to develop and obtain the regulatory approval of the 2020 Licensed Assets worldwide. We are further required to use commercially reasonable efforts to commercialize the 2020 Licensed Assets having regulatory approvals in certain specified countries (U.S., UK, France, Germany, Italy, and Spain). We are not required to pay any development, regulatory or sales milestone payments under the 2020 Xencor Agreement. We are required to pay Xencor tiered royalties on annual net sales of successfully commercialized products utilizing the 2020 Licensed Assets. The royalty percentage rates vary by geographic areas and range from the mid-single digits to the mid-teens. On a region-by region basis and product-by-product basis, the term during which the royalties are payable by us to Xencor is until the latest of (a) last-to-expire licensed patent covering the product in the applicable region, (b) the expiration of regulatory exclusivity for the product in the applicable region, or (c) the twelfth anniversary of the first commercial sale of the product in the applicable region. The last-to-expire patent under the 2020 Xencor Agreement will have an expiration 29 Table of Contents date of December 22, 2028 for ZB002 and February 22, 2031 for ZB004, provided the latest application in each of these countries is allowed. The expected termination of the royalty obligations will depend on factors such as the filing of additional patents covering the products during the term of the 2020 Xencor Agreement, the availability and application of patent term extensions and/or expiration of regulatory exclusivity for the products in the applicable region. We are obligated to reimburse Xencor for certain third-party costs as further specified under the 2020 Xencor Agreement. During the years ended December 31, 2024 and 2023, no costs and immaterial third-party costs were reimbursed, respectively. Under the 2020 Xencor Agreement, (i) Xencor owns all know-how and patent rights invented solely by Xencor, (ii) we own all know-how and patent rights invented solely by us; and (iii) Xencor and we jointly own all joint intellectual property. Subject to the license grants under the 2020 Xencor Agreement, both parties may practice the joint intellectual property for all purposes on a worldwide basis without consent of and without a duty of accounting to the other party. Under the 2020 Xencor Agreement, during the term of the agreement and for two years thereafter, we agree we will not develop, manufacture, or commercialize a competing product for any 2020 Licensed Asset (i.e., any product that binds to the same target as such 2020 Licensed Asset). The 2020 Xencor Agreement will remain in effect, on a region-by region basis and product-by-product basis, until the expiration of all royalty payment obligations. The 2020 Xencor Agreement may be terminated by either party for the other party’s uncured material breach or insolvency. Xencor may terminate the 2020 Xencor Agreement if we challenge a licensed patent. We may terminate for convenience on a country-by-country basis with advance notice to Xencor, with the notice period differing based on whether such termination right is exercised prior to or following the first commercial sale. Upon termination, all licenses granted by Xencor to us automatically terminate. We are obligated to assign to Xencor all regulatory filings or approvals specifically related to the terminated assets or products. At Xencor’s sole discretion, we are obligated to transfer (a) our rights under agreements between us and third parties that solely relate to the development, manufacture or commercialization of terminated assets or products, (b) all materials developed by us for use for commercialization of terminated assets or products and (c) any product mark for terminated assets or products. Upon termination, if Xencor elects to continue development and commercialization of terminated assets or products, we are obligated to grant to Xencor (a) an exclusive license under certain of our patent rights and (b) a nonexclusive license under certain of our know-how, where such licenses are irrevocable, perpetual, royalty-bearing and sublicensable solely to develop, manufacture, and commercialize the terminated assets or products. In consideration for these licenses, Xencor is obligated to pay us (a) mid-single digits royalty on net sales of the terminated assets or products if Xencor commercializes such terminated assets or products and (b) low double digits percentage of all payments receives from sublicensees if Xencor sublicenses the licenses granted by us. Xencor’s obligation to make payments for these licenses is, on a product-by-product basis and region-by-region basis, until last-to-expire licensed patent covering the product in the applicable region. 2021 Xencor Agreement In May 2021, we entered into a license agreement (the “2021 Xencor Agreement”) with Xencor to obtain (i) an exclusive, royalty-bearing, sublicensable worldwide license under certain patent rights controlled by Xencor and (ii) a non-exclusive payment bearing license under certain know-how controlled by Xencor to research, develop, manufacture, market and sell obexelimab, an antibody product candidate based on Xencor’s (and its licensors’) proprietary technology. In addition, Xencor granted us a non-exclusive, royalty-free, sublicensable worldwide license under the same patent and know-how rights to develop, manufacture and commercialize companion diagnostics for obexelimab. Xencor obtained the rights to some of the intellectual property licensed to us pursuant to the Upstream Agreements. As such, the 2021 Xencor Agreement provides that the parties agree that some of the licenses granted by Xencor to us constitute sublicenses under the Upstream Agreements and are subject and subordinate to the terms and conditions of the Upstream Agreements. The 2021 Xencor Agreement became effective in November 2021, upon the execution of an amendment to the 2021 Xencor Agreement and Zenas’ concurrent issuance to Xencor of a warrant with a fair value of $20.7 million to Xencor as initial consideration providing Xencor the right to acquire additional equity, such that its total equity in Zenas would be 15% of its fully diluted capitalization at the completion of our Series B financing. Under the 2021 Xencor Agreement, we are obligated to use commercially reasonable efforts to conduct all future preclinical, clinical, regulatory and other activities necessary to develop and obtain the regulatory approval of obexelimab worldwide. We are further required to use commercially reasonable efforts to commercialize obexelimab following regulatory approvals in certain specified countries (U.S., UK, France, Germany, Italy, and Spain). We were obligated to 30 Table of Contents make development milestone payments of up to $10.0 million, at Xencor’s option either in cash or fully-paid newly issued shares, which milestone payment was paid in Series B Preferred Shares in June 2023. We are obligated to make regulatory milestone payments up to $75.0 million. We are also obligated to make one-time sales milestone payments up to $385.0 million upon achieving milestone events of net sales in a given calendar year in the territory equal to certain threshold amounts. In addition, we are required to pay Xencor tiered royalties on annual net sales of successfully commercialized products utilizing obexelimab, with the royalty rates varying based on regions and ranging from the mid-single digits to the mid-teens. On a region-by region basis and product-by-product basis, the term during which the royalties are payable by us to Xencor is until the latest of (i) the last-to-expire licensed patent covering the product in the applicable region, (ii) the expiration of regulatory exclusivity for the product in the applicable region, or (c) the twelfth anniversary of the first commercial sale of the product in the applicable region. The last-to-expire patent under the 2021 Xencor Agreement will have an expiration date of October 6, 2041, provided the latest application in each of these countries is allowed. The expected termination of the royalty obligations will depend on factors such as the filing of additional patents covering product during the term of the 2021 Xencor Agreement, the availability and application of patent term extensions and/or expiration of regulatory exclusivity for the product in the applicable region. Under the 2021 Xencor Agreement, we agree we will not research or develop obexelimab in a way that would produce a molecule that would be classified as obexelimab or an obexelimab product. In addition, during the term and for two years thereafter, we agree not to develop, manufacture, or commercialize a competing product to obexelimab (i.e., any product that binds to CD19 and incorporates FcγRIIb Technology). During the term, Xencor is obligated to refrain from developing, manufacturing, or commercializing a competing product to obexelimab as well. The non-competes do not apply to any pre-existing activity for a competing product of an acquirer, subject to customary restrictions on such activity following such acquisition. The 2021 Xencor Agreement will remain in effect, on a region-by region basis and product-by-product basis, until the expiration of all royalty payment obligations. The 2021 Xencor Agreement may be terminated by either party for the other party’s uncured material breach or insolvency. We may terminate for convenience on a country-by-country basis with advance notice to Xencor, with the notice period differing based on whether such termination right is exercised prior to or following the first commercial sale. Upon termination, all licenses granted by Xencor to us automatically terminate. We are obligated to assign to Xencor all regulatory filings or approvals specifically related to the terminated assets or products. At Xencor’s sole discretion, we are obligated to transfer (a) our rights under agreements between us and third parties that solely relate to the development, manufacture or commercialization of terminated assets or products, (b) all materials developed by us for use for commercialization of terminated assets or products; and (c) any product mark in relation to the Compound or the Products. Upon termination, if Xencor elects to continue development and commercialization of terminated assets or products, we are obligated to grant to Xencor (a) an exclusive license under certain of our patent rights, and (ii) a nonexclusive license under certain of our know-how, where such licenses are irrevocable, perpetual, royalty-bearing and sublicensable solely to develop, manufacture, and commercialize the terminated assets or products. In consideration for these licenses, Xencor is obligated to pay us (a) mid-single digits royalty on net sales of the terminated assets or products if Xencor commercializes such terminated assets or products and (b) low double digits percentage of all payments receives from sublicensees if Xencor sublicenses the licenses granted by us. Xencor’s obligation to make payments for these licenses is, on a product-by-product basis and region-by-region basis, until the last-to-expire licensed patent covering the product in the applicable region. License Agreement with Bristol-Myers Squibb On August 30, 2023 (the “BMS Effective Date”), we entered into a strategic license and collaboration agreement with BMS (the “BMS Agreement”) under which we provided (a) an exclusive (even as to us) license under certain of our patents and joint patents to be developed under the BMS Agreement, and (b) a non-exclusive license under certain of our know-how. The license grants are for BMS to (a) develop, manufacture (subject to our rights to be the exclusive manufacturer for BMS for a certain period of time), commercialize or otherwise exploit our proprietary CD19 x FcγRIIb antibody, obexelimab (the “Compound”) and any biological product (irrespective of presentations, formulations or dosages) containing the Compound but not any of our other proprietary active ingredient (the “Product”) for treatment of any disease in human or animal in the BMS Territory and (b) conduct development and manufacture of the Compound and Products outside the BMS Territory provided that the Compound and Product are solely used in the BMS Territory. We also provided BMS a non-exclusive and royalty-free license under the same patent and know-how rights for BMS to develop, 31 Table of Contents manufacture, commercialize, or otherwise exploit companion diagnostics for the Compound and Products in the BMS Territory. We retain all rights to commercialize obexelimab outside of the BMS Territory. Under the BMS Agreement, during the term of the BMS Agreement and for a certain period thereafter, BMS has agreed not to develop, manufacture, or commercialize in the BMS Territory a competing product to obexelimab. We have similarly agreed, during the term of the BMS Agreement and for a certain period thereafter, not to develop, manufacture of commercialize in the BMS Territory a product that competes with obexelimab. The non-competes do not apply to any pre-existing activity for a competing product of an acquirer, subject to customary restrictions on such activity following such acquisition. Under the BMS Agreement, we own all intellectual property in (a) improvements and modification to our pre-existing intellectual property, irrespective of which party develops such improvements and modification, (b) any item relating solely to the Compound and Products derived from use of our pre-existing intellectual property and confidential information, irrespective of which party develops such item and (c) any item generated solely by us in relation to the BMS Agreement. With the exclusion of intellectual property allocated as our intellectual property pursuant to (a) or (b) in the foregoing, (a) BMS shall own intellectual property generated solely by BMS under this Agreement and (b) parties will jointly own all other jointly developed intellectual property. As part of the BMS Agreement, BMS is solely responsible for conducting all development activities required to obtain regulatory approval for the Compound or Products in the BMS Territory and BMS is obligated to use commercially reasonable efforts to develop at least one Product and seek and maintain regulatory approvals for such Product in Japan and certain other jurisdictions in the BMS Territory. The parties agreed that we will manufacture and supply and BMS will exclusively purchase all of BMS’s requirements of (a) Products (and placebo) for development in the BMS Territory, subject to the terms of a separate clinical supply agreement and clinical supply quality agreement, to be executed after the BMS Effective Date and (b) finished Products for commercialization in the BMS Territory, subject to the terms of a separate commercial supply agreement and commercial supply quality agreement, to be executed within a certain number of months prior to the first regulatory approval in the BMS Territory. However, BMS may elect to manufacture the Product itself or via a third party (a) at any time after a certain period following the BMS Effective Date or (b) during such period following the BMS Effective Date if we fail to supply above a certain threshold quantity of the Product ordered in any given calendar quarter. BMS has exclusive rights to commercialize the Product in the BMS Territory and is obligated to use commercially reasonable efforts to commercialize Products in Japan and certain other jurisdictions in the BMS Territory after obtaining the applicable regulatory approvals. Under the terms of the BMS Agreement, we have received a one-time upfront payment of $50.0 million. We are entitled to receive further separate development and regulatory milestone payments up to $79.5 million and sales milestone payments up to $70.0 million upon BMS achieving certain net sales milestones in a given calendar year in the BMS Territory. In addition, if BMS successfully develops and commercializes the Product in the BMS Territory, BMS will pay us tiered royalties ranging from (a) the mid-teens to very-low twenties for net sales of Product in Japan and (b) high single digit to low-teens for net sales of Product in all other countries in the BMS Territory, subject to specified reductions. On a country-by-country basis, the term during which the royalties are payable to us is until the latest of (a) the last-to-expire licensed patent covering the Product, (b) the expiration of regulatory exclusivity for the Product or (c) the twelfth anniversary of the first commercial sale of the Product. As of the date of this prospectus, the last-to-expire patent under the BMS Agreement will have an expiration date of October 2, 2044, provided the latest application in each of these countries is allowed. The expected termination of the royalty obligations will depend on factors such as the filing of additional patents covering the Product during the term of the BMS Agreement, the availability and application of patent term extensions and/or expiration of regulatory exclusivity for the Product in the BMS Territory. Finally, BMS will be required to pay a portion of the costs associated with our ongoing INDIGO Trial, in which BMS is participating, as well as any other global study in which BMS elects to participate. During the years ended December 31, 2024 and 2023, we recorded $6.0 million and $4.1 million, respectively, as a reduction to research and development expense for costs associated with our INDIGO Trial that will be reimbursed by BMS. We recognized no revenue during the fiscal year ended December 31, 2024 pursuant to the BMS Agreement. 32 Table of Contents The BMS Agreement will remain in effect, on a country-by-country basis, until the expiration of all royalty payment obligations, and may be earlier terminated by either party for the other party’s uncured material breach or insolvency. BMS may terminate for convenience on a country-by-country basis with advance notice to us, with the notice period differing based on whether such termination right is exercised prior to or following the first commercial sale. In addition to customary events of termination, we also have a right to terminate the agreement (a) automatically upon written notice if the upstream Xencor License Agreement terminates and (b) with written notice if BMS challenges the licensed patents. Upon termination of the BMS Agreement, all licenses granted by us to BMS will automatically terminate and BMS is obligated to cease developing, manufacturing (subject to any transition assistance) and commercializing the Compound and Products in the BMS Territory. Additionally, BMS is obligated to transfer to us all regulatory filings and regulatory approvals related to the Compound or the Products in the Field in the BMS Territory. BMS is further obligated, at our sole discretion, to assign to us (to the extent permissible) (a) BMS’s rights under agreements between BMS and third parties that solely relate to the development, commercialization or manufacture of the Compound or the Products, (b) documentation relating to the commercialization of the Compound or the Products in the BMS Territory; and (c) any BMS owned marks for the Compound or the Products. BMS is obligated to provide reasonable transition supply assistance with respect to any agreement for manufacturing Compound or Products transferred to us, including manufacturing the Compound or Products for up to 18 months following termination. Intellectual Property We own or license patents in the U.S. and foreign countries that protect our products, their methods of use and manufacture, as well as other innovations important to our business, and in order to help bring new therapies to patients. We consider the overall protection of our patents, trademarks, licenses and other intellectual property rights to be of material value. We also rely on trade secrets to protect aspects of our business that are not amenable to, or that we do not consider appropriate for, patent protection. Our success will, in part, depend on our ability to obtain and maintain patent and other proprietary protection for commercially important technology, inventions and know-how related to our business, defend and enforce our patents, preserve the confidentiality of our trade secrets and operate without infringing the valid and enforceable patents and other proprietary rights of third parties. We also rely on regulatory protection, particularly biological data exclusivity, know-how, continuing technological innovation and in-licensing opportunities to develop, strengthen and maintain the proprietary position of our products and development programs. In the biopharmaceutical industry, a substantial portion of an innovative product’s commercial value is usually realized during the period in which the product has exclusivity. A product’s exclusivity is generally determined by two forms of intellectual property: patent rights held by the innovator company and any regulatory forms of exclusivity to which the innovative drug is entitled. Patents are a key determinant of exclusivity for most pharmaceuticals. Patents provide the innovator with the right to exclude others from practicing an invention related to the medicine. Patents may cover, among other things, the active ingredient(s), various uses of a drug product, discovery tools, pharmaceutical formulations, biomarkers, drug delivery mechanisms and processes for (or intermediates useful in) the manufacture of products. The protection afforded by a patent extends for a 20-year term from its filing date, without taking into account any potential patent term adjustment or extension. The protection provided by a patent depends on the scope of its coverage and the availability of meaningful legal remedies to enforce patent claims in the country or countries where it has issued. Market exclusivity can also be influenced by regulatory data protection (“RDP”). Many developed countries provide certain non-patent incentives for the development of medicines. For example, in the U.S., EU member states, UK, Japan, and certain other countries, RDP intellectual property rights are offered to: (i) provide a time period of data protection during which a generic company is not allowed to rely on the innovator’s data in seeking approval; (ii) restore patent term lost during drug development and approval; and (iii) provide incentives for research on medicines for rare diseases, or orphan drugs, and on medicines useful in treating pediatric patients. These incentives may extend a product’s market exclusivity period beyond the patent term. 33 Table of Contents Patent Portfolio As of March 11, 2025, we own or exclusively in-license 14 patent families that specifically cover our product candidates obexelimab (our CD19 x FcγRIIb antibody), ZB002 (our anti-TNFα antibody), and ZB004 (our CTLA-4-Ig fusion protein). These families include 14 issued U.S. patents, nine pending U.S. applications, 123 issued foreign patents, four pending PCT applications and 41 pending foreign patent applications in Australia, Brazil, Canada, China, Eurasia, Europe, Hong Kong, Israel, Japan, Malaysia, Mexico, New Zealand, Saudi Arabia, Singapore, South Africa, South Korea, Taiwan and the United Arab Emirates. In addition, we own or exclusively in-license eight U.S. provisional patent applications, which belong to four different patent families, within the priority year. Any U.S. or foreign patents issued from national stage filings of our owned, or exclusively in-licensed PCT patent applications, any U.S. patents issued from our exclusively in-licensed non-provisional applications, and any U.S. patents or foreign patents issued from non-provisional applications we may file in connection with our provisional patent applications would be scheduled to expire on various dates from 2027 through 2045. All expected expiration dates provided herein are based on a 20-year term, without taking into account any possible PTA or PTE and assuming payment of all appropriate maintenance, renewal, annuity or other governmental fees. Obexelimab Obexelimab is a bifunctional, non-cytolytic, humanized monoclonal antibody that binds CD19 and FcγRIIb to inhibit B-lineage cell activity. As of March 11, 2025, we own or exclusively in-license from Xencor ten patent families that specifically cover the composition of matter, mechanism of action, manufacturing, biomarkers and the clinical uses of obexelimab for treating IgG4-RD, SLE, MS and wAIHA. A first patent family specifically covers the composition of matter of obexelimab and includes six issued patents and two pending applications in the U.S., and 21 issued foreign patents in Australia, Hong Kong, India, Israel and various European countries including Belgium, Denmark, France, Germany, Ireland, Italy, Latvia, Lithuania, Luxembourg, Monaco, Netherlands, Spain, Sweden, Switzerland, and UK. The 20-year statutory term for the patents issued in this family expires in May 2028, excluding any extension of patent term that may be available. A second patent family is directed to obexelimab’s mechanism of action and includes one issued patent and one pending application in the U.S., five pending applications in Canada, Europe, Hong Kong and Japan, and 20 issued patents in Japan and European countries including Austria, Belgium, Denmark, France, Finland, Germany, Hungary, Ireland, Italy, Netherlands, Norway, Poland, Portugal, Spain, Switzerland, Sweden, Turkey and UK. The 20-year statutory term for any patents issued in this family expires in June 2037, excluding any extension of patent term that may be available. A third patent family is directed to the use of biomarkers for treating autoimmune diseases (e.g., SLE) and includes one pending U.S. application, and 13 pending applications in Australia, Brazil, Canada, China, Eurasia, Europe, Hong Kong, Israel, Japan, South Korea, Mexico, South Africa and Taiwan. The 20-year statutory term for any patents issued in this family would expire in October 2041, excluding any extension of patent term that may be available. A fourth patent family is directed to the clinical use of obexelimab for treating IgG4-RD, currently including one pending U.S. Application, and 17 pending applications in Australia, Brazil, Canada, China, Eurasia, Europe, Isreal, Japan, Malaysia, Mexico, New Zealand, Saudi Arabia, Singapore, South Africa, South Korea, Taiwan and the United Arab Emirates. The 20-year statutory term for any patents issued in this family would expire in June 2043, excluding any extension of patent term that may be available. A fifth patent family is directed to the clinical use of obexelimab for treating AIHA, including wAIHA, currently including a pending PCT application and a Taiwanese application. The 20-year statutory term for any patents issued in this family would expire in April 2044, excluding any extension of patent term that may be available. A sixth patent family is directed to the clinical use and dosing regimen of obexelimab for treating forms of MS, including RMS, and currently including a pending PCT application and a pending U.S. application, and a pending Taiwanese application. The 20-year statutory term for any patents issued in this family would expire in October 2044, excluding any extension of patent term that may be available. 34 Table of Contents A seventh patent family is directed to the clinical use and dosing regimen of obexelimab for treating forms of MS, including RMS, and currently including a pending PCT application, a pending U.S. application, and a pending Taiwanese application. The 20-year statutory term for any patents issued in this family would expire in January 2045, excluding any extension of patent term that may be available. An eighth patent family is directed to the SC administration of obexelimab for treating SLE currently including a pending PCT application, a pending U.S. application, and a pending Taiwanese application. The 20-year statutory term for any patents issued in this family would expire in January 2045, excluding any extension of patent term that may be available. A ninth patent family is directed to the manufacturing processes for obexelimab currently including one provisional application. Assuming the provisional application is converted to a non-provisional application at the 12-month from priority deadline, the 20-year statutory term for any patents issued in this family would expire in June 2045, excluding any extension of patent term that may be available. A tenth patent family is related to the clinical use of obexelimab for treating wAIHA currently including two provisional applications within the priority year. Assuming the provisional applications are converted to a non-provisional application at the 12-month from priority deadline, the 20-year statutory term for any patents issued in this family would expire in October 2045, excluding any extension of patent term that may be available. A PTE of up to five years may be available and can be applied in one of these families as appropriate. ZB002 ZB002 is an anti-TNFα monoclonal antibody with the Xtend technology modified to have an extended half-life as compared to existing anti- TNFα therapies. As of March 11, 2025, we exclusively own or in-licensed two patent families covering ZB002. A first patent family specifically covers the full-length amino acid sequences of ZB002, including four issued patents in the U.S., Brazil, Japan and Russia, and two pending applications in Europe and Hong Kong. The 20-year statutory term for U.S. patents in this family expires in October 2027 and any foreign patents that are in this family are expected to expire in December 2028, excluding any extension of patent term that may be available. A second patent family is directed to the formulation and dosing of ZB002 in treating autoimmune diseases including one pending U.S. application, one pending PCT application and one pending application in Taiwan. The 20-year statutory term for any patents issued in this family would expire in March 2045. A PTE of up to five years may be available and can be applied in one of these families as appropriate. ZB004 ZB004 is a CTLA-4-Ig fusion protein with the Xtend technology modified to have an extended half-life versus existing CTLA-4-Ig fusion protein therapies. As of March 11, 2025, we own or exclusively in-licensed two patent families relating to the composition of matter of ZB004 and related methods of use. A first patent family specifically covers the composition of matter and related methods of use ZB004 including six issued patents and one pending application in the U.S., and 79 issued foreign patents in Australia, Canada, China, Hong Kong, India, Japan, South Korea and European countries including Albania, Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lichtenstein, Lithuania, Luxembourg, Macedonia, Malta, Monaco, Netherlands, Norway, Poland, Portugal, Romania, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, and UK. The 20-year statutory term for the patents issued in this family expires in February 2031, excluding any extension of patent term that may be available. A second patent family is related to the formulation and dosing regimen of ZB004 in treating autoimmune diseases currently including two provisional applications within the priority year. Assuming the provisional applications are converted to a non-provisional application at the 12-month from priority deadline, the 20-year statutory term for any patents issued in this family would expire in September 2045. A PTE of up to five years may be available and can be applied in one of these families as appropriate. Trademark Portfolio The Company owns trademark applications and registrations for “Zenas BioPharma” and the Zenas BioPharma logo, and the “lightning bold” design in the U.S. and other foreign jurisdictions. ​ 35 Table of Contents Manufacturing We do not own or operate, and currently have no plans to establish, any manufacturing facilities. We have engaged, and currently rely on, a single third-party CMO, WuXi Biologics, for the supply of our product candidates for use in our preclinical studies and clinical trials. In addition, we have selected new CMOs in the U.S., which are not affiliated with Wuxi Biologics, to establish additional sources of supply for drug substance and drug product for both commercial and clinical use. However, should our CMO, Wuxi Biologics, become unavailable to us for any reason, we believe that we would incur delay and cost in order to complete the manufacturing validation and qualification process for such replacements. We maintain a master services agreement with Wuxi Biologics pursuant to which it provides biologics development and manufacturing services on a per-project basis. We may terminate the master services agreement at any time for convenience in accordance with the terms of the agreement. We may also terminate the master services agreement in the event that Wuxi Biologics does not obtain or maintain any material governmental license or approval in accordance with the terms of the agreement. The agreement includes confidentiality and intellectual property provisions to protect our proprietary rights related to our product candidates. While any reduction or halt in supply from the CMO could limit our ability to develop our product candidates until a replacement CMO is found and qualified, we believe that we have sufficient supply to support our current clinical trial programs. See “Risk Factors” for additional information. We have a long-term commercial supply agreement with WuXi Biologics to fulfill and secure obexelimab drug substance and drug product for an anticipated commercial launch, if approved. In addition, we have selected new CMOs in the U.S., which are not affiliated with WuXi Biologics, to establish additional sources of supply for drug substance and drug product for both commercial and clinical use. For the medical device component of our product (i.e., prefilled syringe or autoinjector), we plan to utilize device assembly facilities in the U.S. or EU for the global supply. While the drug substances used in our product candidates are manufactured by more than one supplier, we rely on a single third-party manufacturer to manufacture and supply the drug substances, drug products, raw materials, samples, components and other materials for our product candidates. In the event it is necessary or advisable to acquire supplies from alternative sources, we might not be able to obtain them at reasonable prices, or at all. It could also require significant time and expense to transfer our manufacturing processes to another company. If we need to change manufacturers for any reason, we will be required to verify that the new manufacturer maintains facilities and procedures that comply with applicable quality standards, regulations and guidelines, and we may be required to conduct additional studies. Additionally, to adequately meet our projected manufacturing needs for commercializing obexelimab and our other product candidates, our CMOs will need to scale-up production or we will need to secure additional suppliers. Processes for producing obexelimab drug substance and drug product for commercial supply have been developed and defined. We believe the drug substance and drug product processes for obexelimab and our other product candidates are amenable to scale-up. Sales, Marketing and Commercialization None of our product candidates have been approved for sale in any country. We hold global development and commercialization rights to obexelimab, excluding Japan, Taiwan, South Korea, Singapore, Hong Kong and Australia, which we have licensed to BMS. We also hold the global development and commercialization rights to ZB002 and ZB004. If our product candidates receive FDA or EMA approval, we intend to build our own commercialization infrastructure in the U.S. and Europe, to market and sell our products. For Asia and other geographies, we plan to conduct the initial clinical development work and then seek to enter into an agreement with a third party to complete the clinical development work, obtain regulatory approval, and ultimately commercialize in these territories. However, we intend to continually evaluate the economics of potentially commercializing our product candidates ourselves, if approved, versus other strategic commercialization arrangements. We currently have no sales, marketing or commercialization capabilities and have no experience as a company performing such activities. However, we intend to build the necessary capabilities and infrastructure over time as our product candidates continue to advance through clinical development. We believe that clinical data, the size of the market 36 Table of Contents opportunity and the size of the required commercial infrastructure will influence our commercialization plans and decision making. Competition The biotechnology and pharmaceutical industries are characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary drugs. While we believe that our knowledge, experience and scientific resources provide us with competitive advantages, we face potential competition from many different sources, including large and specialty pharmaceutical and biotechnology companies, academic research institutions and governmental agencies, as well as public and private research institutions. Any product candidates that we successfully develop and commercialize, if approved, will compete with existing therapies and new therapies that may become available in the future. The key competitive factors affecting the success of all of our product candidates, if approved, are likely to be their safety, efficacy, convenience, price, the level of generic competition, the existence of therapeutic alternatives and the availability of coverage and reimbursement from government and other third-party payors. Many of the companies against which we are competing, or against which we may compete in the future, have significantly greater financial resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approvals and marketing approved drugs than we do. Mergers and acquisitions in the pharmaceutical and biotechnology industries may result in even more resources being concentrated among a smaller number of our competitors. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to, or necessary for, our programs. We are currently developing obexelimab for IgG4-RD, MS, and SLE. There are currently no approved products for IgG4-RD. A number of products are approved for MS and two products are approved for SLE. However, there are a number of product candidates in clinical development by other companies for IgG4-RD, MS, and SLE which may become available in the future. Potentially competitive therapies by indication fall primarily into the following groups of treatment: IgG4-RD: ● UPLIZNA (inebilizumab-cdon), an anti-CD19 antibody being developed by Amgen Inc., for which Amgen filed a BLA and was granted Priority Review based on the results of its Phase 3 trial; ● a small molecule Bruton’s tyrosine kinase (“BTK”) inhibitor in a Phase 2 trial, being developed by Sanofi S.A.; ● other clinical or preclinical small molecules, biologics (including cell-based therapies), or other therapeutic modalities that may be or are being developed for IgG4-RD; and ● other therapies such as corticosteroids and immunosuppressants like cyclophosphamide and rituximab have been used off-label. While these other therapies have not been shown to be effective, and carry significant side effects, their off-label use could reduce or delay treatment in the addressable patient population for obexelimab. MS: ● approved monoclonal antibody biologic therapies including anti-CD20 antibodies such as Ocrevus marketed by F. Hoffmann-La Roche Ltd., Kesimpta marketed by Novartis AG, Briumvi marketed by TG Therapeutics Inc., an anti-CD52 antibody Lemtrada marketed by Sanofi S.A., and an α4-integrin antibody Tysabri marketed by Biogen; ● approved non-antibody-based injectable therapies including interferon beta-1a therapies such as Avonex marketed by Biogen, Plegridy marketed by Biogen, Betaseron marketed by Bayer AG, Extavia marketed by 37 Table of Contents Novartis AG, Rebif marketed by Merck KGaA, and myelin basic protein-based therapies such as Copaxone marketed by Teva Neuroscience Inc.; ● approved small molecule oral therapies including Aubagio marketed by Genzyme Corporation, Bafiertam marketed by Banner Life Sciences, Gilenya marketed by Novartis AG, Mavenclad marketed by Merck KGaA, Mayzent marketed by Novartis AG, Ponvory marketed by Janssen Pharmaceuticals, Inc., Tascenso ODT marketed by Cycle Pharmaceuticals Ltd., Tecfidera marketed by Biogen, Vumerity marketed by Biogen, and Zeposia marketed by Bristol Myers Squibb Company; ● three small molecule BTK inhibitor programs in Phase 3 development by Sanofi S.A., Novartis AG, and Hoffmann-La Roche Ltd.; ● a vidofludimus calcium program in Phase 3 development by Immunic Therapeutics Inc.; ● a small molecule selective tyrosine kinase inhibitor program in Phase 3 development by AB Science; ● an anti-CD40/CD40L antibody in a Phase 3 trial being developed by Sanofi S.A; ● several Phase 2 trial programs evaluating multiple targets / mechanisms of action including but not limited to CD19, BTK, M1R (muscarinic type 1 receptor), BLyS/APRIL, MOG (myelin oligodendrocyte glycoprotein), VLA-4 (very late antigen 4), Treg cells, undisclosed targets / mechanisms and allogenic, autologous, mesenchymal, and CAR-T cell therapies; ● other clinical or preclinical disease modifying small molecules, biologics, or other therapeutic modalities that may be or are being developed for MS; and ● and, approved generic and biosimilar therapies. SLE: ● approved therapies including an anti-BLyS antibody Benlysta marketed by GSK plc., an anti-IFNAR (type I interferon receptor) antibody Saphnelo marketed by AstraZeneca plc., and a dual antagonist of BlyS and APRIL Tai’ai approved and marketed only in China, by RemeGen Co., Ltd.; ● an anti-CD40L (CD40 ligand) pegylated Fab (antigen binding fragment) program in a Phase 3 clinical trial, being developed by UCB Biopharma SRL; ● an anti-BDCA2 (blood dendritic cell antigen 2) antibody program in Phase 3 trials, being conducted by Biogen Inc.; ● a dual antagonist of BLyS and APRIL program in a Phase 3 (ex-China) trial, being developed by RemeGen Co., Ltd.; ● two anti-CD20 antibody programs in Phase 3 trials, being developed by F. Hoffmann-La Roche Ltd. and Beijing Mabworks Biotech Co., Ltd., the latter in China only; ● a small molecule tyrosine kinase 2 (“TYK2”) inhibitor in Phase 3 trials, being developed by Bristol Myers Squibb Company; ● a sphingosine-1-phosphate 1 receptor modulator in Phase 3 trials, being developed by Idorsia Pharmaceuticals Ltd.; ● a small molecule Janus kinase inhibitor in Phase 3 trials, being developed by AbbVie Inc.; 38 Table of Contents ● an anti-BAFF-R antibody program in Phase 3 trials, being developed by Novartis AG; ● several Phase 2 trial programs evaluating multiple targets / mechanisms of action including but not limited to TLR7/8, CD28/ICOS, CD40/CD40L, BAFF/APRIL, IL2, IL21, CRL4-CRBN, IFNB1, BTLA, FcRn, TYK2, BTK, CD22, CD32B/CD79B, CD19, a CD19 CAR-γδT program, CD19/CD20/BCMA-CAR T programs and undisclosed targets / mechanisms; ● other clinical or preclinical small molecules, biologics, or other therapeutic modalities that may be or are being developed for SLE; and ● other therapies such as antimalarials (e.g., hydroxychloroquine), corticosteroid, and immunosuppressants (e.g., cyclophosphamide or rituximab) have been used off-label. While these other therapies have not been shown to be effective, and carry significant side effects, their off-label use could reduce or delay treatment in the addressable patient population for obexelimab. We are also developing ZB002, an anti-TNFα therapy with an extended half-life. The TNFα-binding region within the fragment variable (Fv) domain has an identical amino acid sequence to Humira (adalimumab). The fragment crystallizable (Fc) domain consists of a hybrid immunoglobulin (IgG1/2) constant region containing amino acid substitutions for extended half-life. There are 5 FDA-approved innovator anti-TNF programs for various indications including Humira marketed by AbbVie Biotechnology Ltd., Enbrel marketed by Amgen Inc., Remicade, marketed by Janssen Biotech, Inc., Simponi, marketed by Janssen Biotech, Inc., and Cimzia, marketed by UCB, Inc. In addition to these five innovator anti-TNF programs, a number of biosimilar anti-TNF programs are FDA-approved including Humira biosimilars (such as Amjevita marketed by Amgen Inc., Abrilada marketed by Pfizer Inc., Cyltezo marketed by Boehringer Ingelheim Pharmaceuticals, Inc., Hadlima Organon group of companies, Hulio marketed by Veritas Inc., Hyrimoz marketed by Sandoz Inc., Idacio marketed by Fresenius Kabi USA, LLC, Yuflyma marketed by Celltrion Healthcare Co., Ltd., and Yusimry marketed by Coherus BioSciences, Inc.). ZB004 is a CTLA-4-Ig fusion protein with an extended half-life and potential improved potency versus existing CTLA-4-Ig fusion protein therapies. There are two marketed CTLA-4-Ig fusion protein therapies. Orencia, marketed by BMS, is FDA-approved for rheumatoid arthritis, polyarticular juvenile idiopathic arthritis, and prophylaxis of acute graft versus host disease. Nulojix, marketed by BMS, is FDA-approved for prophylaxis of organ rejection in adult patients receiving a kidney transplant. One Orencia biosimilar program recently entered Phase 1 clinical development. Government Regulation Government authorities at the federal, state and local level in the U.S. and in other countries and jurisdictions, including the EU, extensively regulate, among other things, the research, development, testing, manufacture, pricing, reimbursement, sales, quality control, approval, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, post-approval monitoring and reporting and import and export of biological products such as those we are developing. We, along with our CMOs, CROs and third-party vendors, will be required to satisfy these requirements in each of the countries in which we wish to conduct studies or seek approval or licensure of our product candidates. The processes for obtaining marketing approvals in the U.S. and in foreign countries and jurisdictions, along with subsequent compliance with applicable statutes, regulations, and other regulatory requirements, require the expenditure of substantial time and financial resources. Licensure and Regulation of Biologics in the U.S. We are currently developing product candidates that are biological products, or biologics. In the U.S., where we are initially focusing our product development, the FDA regulates biologics under the FDCA and the Public Health Service Act (“PHSA”), and their implementing regulations. Biologics are also subject to other federal, state and local statutes and regulations. Our product candidates are early-stage and have not been approved for marketing in the U.S. 39 Table of Contents An applicant seeking approval to market and distribute a new biologic in the U.S. must satisfactorily complete each of the following steps: ● preclinical laboratory tests, animal studies and formulation studies performed in accordance with the FDA’s GLPs; ● manufacture of the drug substance and drug product in accordance with the FDA’s cGMPs, along with required analytical and stability testing; ● submission to the FDA of an Investigational New Drug Application (“IND”) for human clinical testing, which must become effective before human clinical trials may begin; ● approval by an independent IRB, representing each clinical trial site before each clinical trial may be initiated; ● performance of adequate and well-controlled human clinical trials, in accordance with current Good Clinical Practice requirements (“cGCPs”), necessary to establish the safety, potency and purity of the product candidate for each proposed indication; ● preparation and submission to the FDA of a BLA, requesting marketing approval for one or more proposed indications, including submission of detailed information on the manufacture and composition of the product and proposed labeling; ● satisfactory completion of one or more FDA inspections of the manufacturing facility or facilities, including those of third parties, at which the product, or components thereof, are produced to assess compliance with cGMPs and to assure that the facilities, methods and controls are adequate to preserve the product’s identity, strength, quality and purity; ● satisfactory completion of any FDA audits of the preclinical studies and clinical trial sites to assure compliance with GLPs and cGCPs, as applicable, and the integrity of clinical data in support of the BLA; ● payment of user fees under the Prescription Drug User Fee Act (“PDUFA”), unless exempted; ● the FDA’s review and approval of the BLA, including consideration of the views of any FDA advisory committee, if applicable; and ● if approved, compliance with any post-approval requirements, including the potential requirement to implement a REMS and any post-approval studies or other post-marketing commitments required by the FDA. Failure to comply with the applicable requirements at any time during the product development process, including preclinical testing, clinical testing, the approval process, or post-approval process, may subject an applicant to delays in the conduct of the study or regulatory review and approval, as well as administrative or judicial sanctions or other consequences. These sanctions or consequences may include, but are not limited to, the FDA’s refusal to allow an applicant to proceed with clinical testing, issuance of clinical holds for planned or ongoing studies, refusal to approve pending applications, suspension or revocation of existing product licenses or approvals, issuance of warning or untitled letters, adverse publicity, product recalls, marketing restrictions, product seizures, import detentions and refusals, total or partial suspension of manufacturing or distribution, injunctions, fines and civil or criminal investigations and penalties brought by the FDA or the Department of Justice (“DOJ”), and other governmental entities, including state agencies. Preclinical Studies and Investigational New Drug Application Once a therapeutic product candidate is identified for development, it must undergo preclinical studies (also known as preclinical testing) before any testing may be conducted in humans. Preclinical tests include laboratory evaluations of product chemistry, formulation and stability, as well as studies to evaluate the potential for efficacy and toxicity in animals. The conduct of preclinical tests and formulation of the compounds for testing must comply with federal regulations and 40 Table of Contents requirements, including GLPs. The results of the preclinical tests, together with manufacturing information, analytical data, and plans for the proposed clinical studies, are submitted to the FDA as part of an IND. Some preclinical testing may continue after an IND is submitted. An IND is a request for FDA authorization to administer an investigational new drug product to humans. The IND automatically becomes effective 30 days after receipt by the FDA, unless before that time the FDA raises concerns or questions about the product or the conduct of the proposed clinical trial, including concerns that human research subjects will be exposed to unreasonable health risks. In that case, the IND sponsor and the FDA must resolve any outstanding FDA concerns before the clinical trials can begin. As a result, submission of an IND may or may not result in FDA authorization to begin a clinical trial, or to begin a clinical trial on the terms originally specified by the sponsor in the IND. At any time during the initial 30-day IND review period or while clinical trials are ongoing under the IND, the FDA may impose a partial or complete clinical hold. Clinical holds may be imposed by the FDA when there is concern for patient safety, and may be a result of new data, findings, or developments in clinical, preclinical, and/or chemistry, CMC or where there is non-compliance with regulatory requirements. This order would delay either a proposed clinical trial or cause suspension of an ongoing trial, until all outstanding concerns have been adequately addressed and the FDA has notified the company that investigations may proceed. A separate submission to an existing IND must also be made for each successive clinical trial conducted, and the FDA must grant permission, either explicitly or implicitly, by not objecting before each clinical trial can begin. Human Clinical Trials Clinical trials involve the administration of an investigational drug product to healthy volunteers or patients with the disease or condition to be treated under the supervision of qualified investigators. Clinical trials must be conducted in accordance with GCPs, which establish ethical and data integrity standards for clinical testing, as well as the requirements for informed consent. Clinical trials are conducted under protocols detailing, among other things, the objectives of the trial, dosing procedures, inclusion and exclusion criteria, the parameters to be used in monitoring safety, and the effectiveness criteria to be evaluated. A protocol for each clinical trial and any subsequent protocol amendments must be submitted to the FDA as part of the IND. For clinical trials conducted in the U.S., an IND is required, and each clinical trial must be reviewed and approved by an IRB either centrally or individually at each institution at which the clinical trial will be conducted. The IRB will consider, among other things, clinical trial design, patient informed consent, ethical factors, the safety of human subjects and the possible liability of the institution. An IRB must operate in compliance with FDA regulations. The FDA, IRB or the trial sponsor may suspend a clinical trial at any time on various grounds, including a finding that the trial is not being conducted in accordance with GCPs or IRB requirements or that research subjects or patients are being exposed to an unacceptable health risk. In addition, some clinical trials are overseen by an independent group of qualified experts organized by the sponsor, known as a data safety monitoring board or data monitoring committee. Depending on its charter, this group may recommend continuation of the trial as planned, changes in trial conduct, or cessation of the trial at designated check points based on certain available data from the trial. A sponsor who wishes to conduct a clinical trial outside the U.S. may, but need not, obtain FDA authorization to conduct the clinical trial under an IND. When a foreign clinical trial is conducted under an IND, all FDA IND requirements must be met unless waived. When a foreign clinical trial is not conducted under an IND, FDA may accept the results of the study in support of a BLA if the study was well-designed and conducted in accordance with GCPs, and the FDA is able to validate the data through an onsite inspection if deemed necessary. Clinical trials typically are conducted in three sequential phases, but the phases may overlap or be combined. Additional studies may be required after approval. ● Phase 1 trials are initially conducted in a limited population of healthy subjects to test the product candidate for safety, including adverse effects, dose tolerance, absorption, metabolism, distribution, excretion and PD. In the 41 Table of Contents case of some products designed to address severe or life-threatening diseases, initial human testing is often conducted in patients with the disease, especially when the product may be too inherently toxic to ethically administer to healthy volunteers. ● Phase 2 trials are generally conducted in a limited patient population to identify possible adverse effects and safety risks, evaluate the preliminary efficacy of the product candidate for specific targeted indications and determine dose tolerance and recommended dosage. Multiple Phase 2 clinical trials may be conducted by the sponsor to obtain information prior to beginning larger and more costly Phase 3 clinical trials. ● Phase 3 trials are generally undertaken to further evaluate dosage, provide substantial evidence of clinical efficacy and further test for safety in an expanded and diverse patient population at multiple, geographically dispersed clinical trial sites. A well-controlled, statistically robust Phase 3 trial may be designed to deliver the data that regulatory authorities will use to decide whether or not to approve, and, if approved, how to appropriately label a biologic; such Phase 3 studies are generally referred to as “pivotal,” however, for some investigational products, Phase 2 may be considered pivotal trials if such trials are expected to provide the clinical evidence needed to support a marketing application. In some cases, the FDA may approve a BLA for a product but require the sponsor to conduct additional clinical trials to further assess the product’s safety and effectiveness after approval. Such post-approval trials are typically referred to as confirmatory studies, or Phase 4 clinical trials. These studies are used to gain additional experience from the treatment of patients in the intended therapeutic indication and verify clinical benefit for products approved under accelerated approval regulations. Failure to exercise due diligence with regard to conducting required confirmatory studies could result in withdrawal of approval for products. While the IND is active and before approval, progress reports detailing the results of the clinical trials and preclinical studies performed since the last progress report must be submitted at least annually to the FDA and written IND safety reports must be submitted to the FDA and the investigators for serious and unexpected suspected adverse events, findings from other studies or animal or in vitro testing that suggest a significant risk for human subjects and any clinically important increase in the rate of a serious suspected adverse reaction over that listed in the protocol or investigator brochure. The sponsor must submit an IND safety report within 15 calendar days after the sponsor determines that the information qualifies for reporting. The sponsor also must notify the FDA of any unexpected fatal or life-threatening suspected adverse reaction within seven calendar days after the sponsor’s initial receipt of the information. There are also requirements governing the reporting of ongoing clinical trials and clinical trial results to public registries. Sponsors of certain clinical trials of FDA-regulated products are required to register and disclose information about ongoing clinical trials, including information related to the drug, patient population, phase of investigation, trial sites and investigators. Sponsors are also obligated to disclose the results of completed clinical trials, other than Phase 1 clinical trials, within specific timeframes. Information about applicable clinical trials is published on www.ClinicalTrials.gov, a clinical trials database maintained by the National Institutes of Health. During the development of a new biologic, sponsors are given opportunities to meet with the FDA at certain points. These points may be prior to submission of an IND, at the end of Phase 2, and before a BLA is submitted. Meetings at other times may be requested. These meetings can provide an opportunity for the sponsor to share information about the data gathered to date, for the FDA to provide advice, and for the sponsor and the FDA to reach agreement on the next phase of development. Compliance with cGMPs Concurrent with clinical trials, companies must finalize a process for manufacturing the product in commercial quantities in accordance with cGMPs. The manufacturing process must be capable of consistently producing quality batches of the product and, among other things, companies must develop methods for testing the identity, strength, quality and purity of the final product. Additionally, appropriate packaging must be selected and tested and stability studies must be conducted to demonstrate that the products do not undergo unacceptable deterioration over their shelf life. Before approving a BLA, the FDA will typically inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMPs and 42 Table of Contents adequate to assure consistent production of the product within required specifications. The PHSA emphasizes the importance of manufacturing controls for products like biologics whose attributes cannot be precisely defined. Material changes in manufacturing equipment, location, or process post-approval, may result in additional regulatory review and approval. Review and Approval of a BLA The results of clinical trials and preclinical studies, together with detailed information regarding the manufacturing processes, chemistry and composition of the product, the proposed labeling and other relevant information, are submitted to the FDA as part of a BLA requesting approval to market the product for one or more specified indications. Clinical and preclinical data may come from company-sponsored trials or from a number of alternative sources, including studies initiated by investigators, and the BLA must include any negative and ambiguous results, as well as positive findings. To support marketing approval, the data submitted must be sufficient in quality and quantity to establish the safety, purity, and potency of the investigational product to the satisfaction of the FDA. For most BLAs, the sponsor is required to pay a substantial application user fee at the time of submission and the sponsor of an approved BLA is subject to an annual program fee. Certain exceptions and waivers are available for some of these fees, such as an exception from the application fee for products with orphan designation and a waiver for certain small businesses. The FDA has 60 days after submission of the application to conduct an initial review to determine whether to accept it for filing based on the agency’s threshold determination that it is sufficiently complete to permit substantive review. If the submission has been accepted for filing, the FDA begins an in-depth review of the application. Under the goals and policies agreed to by the FDA under PDUFA, the FDA has ten months from the acceptance date in which to complete its initial review of a standard application and respond to the applicant, and six months for a priority review of the application. The FDA does not always meet its PDUFA goal dates for standard and priority BLAs and the review process may be significantly extended by FDA requests for additional information or clarification. For example, the review process and the PDUFA goal date may be extended by three months if the FDA requests or if the applicant otherwise provides additional data, analysis or information that FDA deems a major amendment. During its review of a BLA, the FDA may refer applications for novel biological products or biological products that present difficult questions of safety or efficacy to an advisory committee. Typically, an advisory committee is a panel of independent experts, including clinicians and other scientific experts, that reviews, evaluates and provides a recommendation as to whether the application should be approved and under what conditions, if any. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions. On the basis of the FDA’s evaluation of the application and accompanying information, including the results of the inspection of the manufacturing facilities and any FDA audits of preclinical and clinical trial sites to assure compliance with GLPs or GCPs, the FDA may approve the BLA or issue a complete response letter. Under the PHSA, the FDA may approve a BLA if it determines the product is safe, pure, and potent, and that the facility in which the product will be manufactured, processed, packaged or held meets standards designed to assure the product’s continued safety, purity and potency. If FDA determines the product meets these standards, it may issue an approval letter authorizing the commercial marketing of the product with specific prescribing information for specific indications. If the application is not approved, the FDA will issue a complete response letter, which will contain the conditions that must be met in order to secure final approval of the application, and when possible, will outline recommended actions the sponsor might take to obtain approval of the application. A complete response letter may require additional clinical data and/or other significant and time-consuming requirements related to clinical trials, preclinical studies or manufacturing. Sponsors that receive a complete response letter have one year to submit information that represents a complete response to the deficiencies identified by the FDA. The FDA will then re-review the application, taking into consideration the response, and determine whether the application meets the criteria for approval. Failure to respond to a complete response letter will serve as a withdrawal of an application. The FDA will not approve an application until issues identified in any complete response letters have been addressed. If the FDA approves a new product, it may limit the approved indication(s) for use of the product. It may also require that contraindications, warnings, or precautions be included in the product labeling. In addition, the FDA may require post-approval studies, including Phase 4 clinical trials, to further assess the product’s efficacy and/or safety after approval. The 43 Table of Contents agency may also require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution restrictions or other risk management mechanisms, including REMS, to help ensure that the benefits of the product outweigh the potential risks. REMS can include medication guides, communication plans for healthcare professionals and elements to assure safe use (also known as ETASU). ETASU can include, but are not limited to, special training or certification for prescribing or dispensing, dispensing only under certain circumstances, special monitoring and the use of patent registries. The FDA may prevent or limit further marketing of a product based on the results of post-market studies or surveillance programs. After approval, if there are any modifications to the approved product, including changes in the indications, dosage forms, labeling, or manufacturing processes or facilities, the sponsor may be required to submit and obtain FDA approval of a new BLA or BLA supplement, which may require the generation of additional data or the conduct of additional preclinical studies and clinical trials. Post-Approval Regulation Upon FDA approval of a BLA, the sponsor will be required to comply with all post-approval regulatory requirements for biologics, as well as any specific post-approval requirements that the FDA has imposed as part of the product or indication’s approval process. The sponsor will be required to report certain adverse reactions and production problems to the FDA, provide updated safety and efficacy information, obtain FDA approval for certain manufacturing and labeling changes, and comply with requirements concerning advertising and promotional labeling, record-keeping, and drug supply chain security. Manufacturers and certain of their subcontractors are required to register their establishments with the FDA and certain state agencies and are subject to periodic unannounced inspections for compliance with ongoing regulatory requirements, including cGMPs. Accordingly, the sponsor and its third-party manufacturers must continue to expend time, money and effort in the areas of production and quality control, as well as pharmacovigilance activities, to maintain compliance with cGMPs and other regulatory requirements. A biological product may also be subject to official lot release, meaning that the manufacturer is required to perform certain tests on each lot of the product before it is released for distribution. If the product is subject to official lot release, the manufacturer must submit samples of each lot, together with a release protocol showing a summary of the history of manufacture of the lot and the results of all of the manufacturer’s tests performed on the lot, to the FDA. The FDA may perform certain confirmatory tests on lots of some products before releasing the lots for distribution. In addition, the FDA strictly regulates the marketing, labeling, advertising and promotion of prescription drug products, including biological products. These regulations include, among other things, standards and regulations for direct-to-consumer advertising, communications regarding unapproved uses, industry-sponsored scientific and educational activities and promotional activities involving the internet and social media. Promotional claims about a drug’s safety or effectiveness are prohibited before the BLA is approved. Once a BLA is approved, the sponsor can make only those claims relating to safety, efficacy, purity and potency that are in accordance with the provisions of the approved label. In the U.S., healthcare professionals are generally permitted to prescribe legally available drugs for uses that are not described in the product’s labeling and that differ from those approved by the FDA. Such off-label uses are common across medical specialties. The FDA does not regulate the practice of medicine or healthcare providers’ choice of treatments. However, FDA regulations do impose rigorous restrictions on manufacturers’ communications of off-label uses. Additionally, promotional materials for prescription drug products must be submitted to the FDA in conjunction with their first use. If a company, including any agent of the company or anyone speaking on behalf of the company, is found to have promoted off-label uses, the company may become subject to adverse public relations and administrative and judicial enforcement by the FDA, the DOJ, or the Office of the Inspector General of the Department of Health and Human Services (“HHS”), as well as state authorities. This could subject a company to a range of penalties that could have a significant commercial impact, including civil and criminal fines and agreements that materially restrict the manner in which a company promotes or distributes drug products. The federal government has levied large civil and criminal fines against companies for alleged improper promotion and has also requested that companies enter into consent decrees or permanent injunctions under which specified promotional conduct is changed or curtailed. The FDA may require testing and surveillance programs to monitor the effect of approved products that have been commercialized, and the FDA has the power to prevent or limit further marketing of a product based on the results of these post-marketing programs. 44 Table of Contents The FDA may withdraw product approval if compliance with regulatory requirements and standards is not maintained or if issues occur after the product reaches the market. Later discovery of previously unknown issues with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical trials to assess new safety risks; or imposition of distribution or other restrictions under a REMS program. Other potential consequences include: ● restrictions on the marketing or manufacturing of the product, including total or partial suspension of production, or complete withdrawal of the product from the market; ● the issuance of safety alerts, Dear Healthcare Provider letters, press releases or other communications containing warnings or other safety information about the product; ● warning letters or untitled letters; ● refusal of the FDA to approve pending applications or supplements to approved applications, or suspension or revocation of product license approvals; ● product recall, seizure or detention, or refusal to permit the import or export of products; ● imposition of clinical holds on ongoing clinical trials; ● mandated modification of promotional materials and labeling and the issuance of corrective information; ● consent decrees, corporate integrity agreements, debarment or exclusion from federal healthcare programs; or ● fines, injunctions or the imposition of civil or criminal penalties. FDA Regulation of Combination Products Certain therapeutic products are comprised of multiple FDA-regulated components, such as drugs and medical devices, that are physically combined and produced as a single entity, packaged together in a single package, or packaged separately but intended to be labeled for use together. These products are known as combination products. We expect that obexelimab and our other product candidates packaged in a prefilled syringe or autoinjector would be subject to regulation as a combination product if consisting of a therapeutic biologic and a delivery device. The constituent elements of such combination products would normally be subject to different FDA regulatory frameworks and regulated by different Centers at the FDA. Depending on the type of combination product, its approval, clearance or licensure may usually be obtained through the submission of a single marketing application; however, FDA could require separate marketing applications for individual constituent parts of the combination product which may require additional time, effort and information. Even when a single marketing application is required for a combination product, such as a BLA for a combination biologic and device product, both FDA’s Center for Biologics Evaluation and Research and FDA’s Center for Devices and Radiological Health may participate in the review. If a product candidate is considered a biologic-device combination product, the sponsor will also need to comply with post-marketing regulatory requirements, including adverse event reporting and applicable portions of the FDA’s Quality System regulation, applicable to combination products. Fast Track, Breakthrough Therapy and Priority Review Designations The FDA has several programs intended to facilitate and expedite development and review of new products that are intended to address an unmet medical need in the treatment of a serious or life-threatening disease or condition. These programs are referred to as fast track designation, breakthrough therapy designation and priority review designation. These designations are not mutually exclusive, and a product candidate may qualify for one or more of these programs. While 45 Table of Contents these programs are intended to expedite product development and approval, they do not alter the standards for FDA approval. The FDA may designate a product for fast track designation if it is intended for the treatment of a serious or life-threatening disease or condition, and preclinical or clinical data demonstrate the potential to address unmet medical needs for such a disease or condition. For products with fast track designation, sponsors may have more frequent interactions with the FDA, the product is potentially eligible for accelerated approval and priority review, if relevant criteria are met, and the BLA may be eligible for “rolling review,” under which the FDA may consider sections of the BLA for review on a rolling basis before the complete application is submitted. This rolling review may be available if the FDA determines, after preliminary evaluation of clinical data submitted by the sponsor, that a product with fast track designation may be effective. The sponsor must also provide, and the FDA must approve, a schedule for the submission of the remaining sections of the BLA, and the sponsor must pay any required user fees upon submission of the first section of the BLA. The FDA’s time goal for reviewing a fast track application does not begin until the last section of the application is submitted. A product may be designated as a breakthrough therapy if it is intended to treat a serious or life-threatening disease or condition and preliminary clinical evidence indicates that the product may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints. The designation includes all of the fast track program features, including eligibility for rolling review. Additionally, the FDA may take certain actions to expedite the development and review of breakthrough therapies, including holding meetings with the sponsor throughout the development process; providing timely advice to the product sponsor regarding development and approval; involving more senior staff managers in the review process; assigning a cross-disciplinary lead for the review team; and taking other steps to design the clinical trials in an efficient manner. The FDA may designate a product for priority review if it is a product that treats a serious condition and, if approved, would provide a significant improvement in safety or effectiveness when compared with other available therapies. A priority review designation is intended to direct the FDA’s attention and resources to the evaluation of such applications, and to shorten the FDA’s goal for taking action on an original BLA from ten months to six months from the acceptance date. Fast track designation, breakthrough therapy designation, and priority review do not change the standards for approval but may expedite the development or approval process. Even if a drug qualifies for one or more of these programs, the FDA may later withdraw or rescind the designation if it decides that the drug no longer meets the conditions for qualification or decides that the time period for FDA review or approval will not be shortened. Accelerated Approval Pathway The FDA may grant accelerated approval to a product candidate designed to treat a serious or life-threatening condition that provides a meaningful therapeutic advantage to patients over existing treatments based upon a determination that the product has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit. For the purposes of accelerated approval, a surrogate endpoint is a marker, such as a laboratory measurement, radiographic image, physical sign, or other measure that is thought to predict clinical benefit but is not itself a measure of clinical benefit. The FDA may also grant accelerated approval for such a condition when the product has an effect on an intermediate clinical endpoint that can be measured earlier than an effect on irreversible morbidity or mortality (“IMM”), and that is reasonably likely to predict an effect on IMM or other clinical benefit, taking into account the severity, rarity or prevalence of the condition and the availability or lack of alternative treatments. The accelerated approval pathway is most often used in settings in which the course of a disease is long, and an extended period of time is required to measure the intended clinical benefit of a product, even if the effect on the surrogate or intermediate clinical endpoint occurs rapidly. Products granted accelerated approval must meet the same statutory standards for safety and effectiveness as those granted traditional approval. The FDA’s approval of a candidate product under the accelerated approval pathway is usually contingent on a sponsor’s agreement to conduct post-approval confirmatory studies to verify and describe the product’s clinical benefit, and the FDA may require such studies to be underway prior to approval. Failure to conduct required post-approval studies, confirm a clinical benefit during post-marketing studies may result in the FDA’s withdrawal of the product from the market on an 46 Table of Contents expedited basis. All promotional materials for therapeutic candidates approved under accelerated regulations are subject to prior review by the FDA. Orphan Drug Designation and Exclusivity Orphan drug designation in the U.S. is designed to encourage sponsors to develop products intended for treatment of rare diseases or conditions. In the U.S., a rare disease or condition is statutorily defined as a condition that affects fewer than 200,000 individuals in the U.S. or that affects 200,000 or more individuals in the U.S. and for which there is no reasonable expectation that the cost of developing and making available the drug or biologic for the disease or condition will be recovered from sales of the product in the U.S. Orphan drug designation qualifies a company for tax credits and market exclusivity for seven years following the date of the product’s marketing approval if granted by the FDA. An application for designation as an orphan product can be made any time prior to the filing of an application for approval to market the product. If orphan drug designation is granted by the FDA, the generic identity of the therapeutic agent and its potential orphan use are disclosed publicly by the FDA. After FDA grants orphan designation, the product must then go through the review and approval process like any other product. A sponsor may request orphan drug designation of a previously unapproved product or new orphan indication for an already marketed product. In addition, a sponsor of a product that is otherwise the same product as an already approved orphan drug may seek and obtain orphan drug designation for the subsequent product for the same rare disease or condition if it can present a plausible hypothesis that its product may be clinically superior to the first drug. More than one sponsor may receive orphan drug designation for the same product for the same rare disease or condition, but each sponsor seeking orphan drug designation must file a complete request for designation. If a product with orphan designation receives the first FDA approval for the disease or condition for which it has such designation or for a select indication or use within the rare disease or condition for which it was designated, the product generally will receive orphan drug exclusivity. Orphan drug exclusivity means that the FDA may not approve another sponsor’s marketing application for the same product for the same indication for seven years, except in certain limited circumstances. If a product designated as an orphan drug ultimately receives marketing approval for an indication broader than what was designated in its orphan drug application, it may not be entitled to exclusivity. Orphan drug exclusivity does not prevent the FDA from approving a different drug for the same disease or condition, or the same drug for a different disease or condition. The period of exclusivity begins on the date that the marketing application is approved by the FDA and applies only to the indication for which the product has been designated. The FDA may approve a second application for the same product for a different use or a second application for a clinically superior version of the product for the same use. The FDA cannot, however, approve the same product made by another manufacturer for the same indication during the market exclusivity period unless it has the consent of the sponsor, or the sponsor is unable to provide sufficient quantities. The FDA has historically taken the position that the scope of orphan exclusivity aligns with the approved indication or use of a product, rather than the disease or condition for which the product received orphan designation. However, in Catalyst Pharms., Inc. v. Becerra , 14 F.4 th 1299 (11 th Cir. 2021), the court disagreed with this position, holding that orphan-drug exclusivity blocked the FDA’s approval of the same drug for all uses or indications within the same orphan-designated disease. On January 24, 2023, the FDA published a notice in the Federal Register to clarify that the FDA intends to continue to apply its longstanding interpretation of the regulations to all matters outside of the scope of the Catalyst order and will continue tying the scope of orphan-drug exclusivity to the uses or indications for which a drug is approved. It is unclear how future litigation, legislation, agency decisions, and administrative actions will impact the scope of the orphan drug exclusivity. Development in Pediatric Patients Under the Pediatric Research Equity Act of 2003, a BLA or BLA supplement thereto must contain data that are adequate to assess the safety and effectiveness of the product for the claimed indications in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. A sponsor who is planning to submit a marketing application for a product that includes a new active ingredient, new indication, new 47 Table of Contents dosage form, new dosing regimen or new route of administration must submit a Pediatric Study Plan (“PSP”) that contains an outline of the proposed pediatric study or studies the applicant plans to conduct, including study objectives and design, any deferral or waiver requests and other information required by regulation. The sponsor and the FDA must reach agreement on the PSP. The FDA or the applicant may request an amendment to the plan at any time. The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of some or all pediatric data until after approval of the product for use in adults, or full or partial waivers from the pediatric data requirements. The FDA must send a non-compliance letter to any sponsor that fails to submit the required assessment, keep a deferral current or fails to submit a request for approval of a pediatric formulation. Unless otherwise required by regulation, the pediatric data requirements do not apply to products with orphan designation. Pediatric Exclusivity Pediatric exclusivity is a type of non-patent marketing exclusivity in the U.S. and, if granted, provides for the attachment of an additional six months of marketing protection to the term of any existing regulatory exclusivity, including orphan exclusivity. This six-month exclusivity may be granted if a BLA sponsor submits pediatric data that fairly respond to a written request from the FDA for such data. The data do not need to show the product to be effective in the pediatric population studied; rather, if the clinical trial is deemed to fairly respond to the FDA’s request, the additional protection is granted. Biosimilars and Exclusivity The ACA, which was signed into law in March 2010, included the BPCIA. The BPCIA established a regulatory scheme authorizing the FDA to approve biosimilars and interchangeable biosimilars. A biosimilar is a biological product that is highly similar to an existing FDA-licensed “reference product.” Under the BPCIA, a manufacturer may submit an application for licensure of a biologic product that is “biosimilar to” or “interchangeable with” a previously approved biological product or “reference product.” In order for the FDA to approve a biosimilar product, it must find that there are no clinically meaningful differences between the reference product and proposed biosimilar product in terms of safety, purity and potency. For the FDA to approve a biosimilar product as interchangeable with a reference product, the agency must find that the biosimilar product can be expected to produce the same clinical results as the reference product in any given patient, and (for products administered multiple times to an individual) that the biologic and the reference biologic may be switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biologic. A product shown to be biosimilar or interchangeable with an FDA-approved reference biological product may rely in part on the FDA’s previous determination of safety and effectiveness for the reference product for approval, which can potentially reduce the cost and time required to obtain approval to market the product. Under the BPCIA, an application for a biosimilar product may not be submitted to the FDA until four years following the date of approval of the reference product. The FDA may not approve a biosimilar product until 12 years from the date on which the reference product was approved. Even if a product is considered to be a reference product eligible for exclusivity, another company could market a competing version of that product if the FDA approves a full BLA for such product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of their product. The BPCIA also created certain exclusivity periods for biosimilars approved as interchangeable products. The law also includes an extensive process for the innovator biologic and biosimilar manufacturer to litigate patent infringement, validity and enforceability prior to the approval of the biosimilar. Since the passage of the BPCIA, many states have passed laws or amendments to laws, including laws governing pharmacy practices, which are state regulated, to regulate the use of biosimilars. U.S. Patent Term Restoration and Extension In the U.S., a patent claiming a new biologic product, its method of use or its method of manufacture may be eligible for a limited patent term extension under the Hatch-Waxman Amendments, which permits a patent extension of up to five years for patent term lost during product development and FDA regulatory review. Assuming grant of the patent for which the extension is sought, the restoration period for a patent covering a product is typically one-half the time between the effective date of the IND and the submission date of the BLA, plus the time between the submission date of the BLA and 48 Table of Contents the ultimate approval date, except that the review period is reduced by any time during which the applicant failed to exercise due diligence. Patent term restoration cannot be used to extend the remaining term of a patent past a total of 14 years from the product’s approval date in the U.S. Only one patent applicable to an approved product is eligible for the extension, and the application for the extension must be submitted prior to the expiration of the patent for which extension is sought. A patent that covers multiple products for which approval is sought can only be extended in connection with one of the approvals. The United States Patent and Trademark Office (“USPTO”) reviews and approves the application for any patent term extension in consultation with the FDA. Federal and State Data Privacy and Security Laws Under HIPAA, HHS has issued regulations to protect the privacy and security of protected health information, used or disclosed by covered entities including certain healthcare providers, health plans and healthcare clearinghouses. HIPAA also regulates standardization of data content, codes and formats used in healthcare transactions and standardization of identifiers for health plans and providers. HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 or HITECH, and their regulations, including the final omnibus rule published on January 25, 2013, also imposes certain obligations on the business associates of covered entities and their covered subcontractors that obtain protected health information in providing services to or on behalf of covered entities or business associates. In addition to federal privacy regulations, there are a number of state laws governing confidentiality and security of health information that are applicable to our business. In addition to possible federal, administrative, civil and criminal penalties for HIPAA violations, state attorneys general are authorized to file civil actions for damages or injunctions in federal courts to enforce HIPAA and seek attorney’s fees and costs associated with pursuing federal civil actions. Accordingly, state attorneys general have brought civil actions seeking injunctions and damages resulting from alleged violations of HIPAA’s privacy and security rules. New laws and regulations governing privacy and security may be adopted in the future as well. Additionally, states, such as California, Virginia and Colorado have recently enacted the consumer privacy laws that grant rights to data subjects and place increased privacy and security obligations on entities handling personal data of consumers or households. While we are not currently subject to laws such as the CCPA, some observers note that the CCPA and similar legislation could mark the beginning of a trend toward more stringent privacy legislation in the U.S., which could increase our potential liability and adversely affect our business. Because of the breadth of these laws and the narrowness of the statutory exceptions under such laws, it is possible that some of our current or future business activities, including certain clinical research, sales and marketing practices and the provision of certain items and services to our customers, could be subject to challenge under one or more of such privacy and data security laws. The heightening compliance environment and the need to build and maintain robust and secure systems to comply with different privacy compliance and/or reporting requirements in multiple jurisdictions could increase the possibility that we may fail to comply fully with one or more of these requirements. If our operations are found to be in violation of any applicable privacy or data security laws or regulations, we may be subject to penalties, including potentially significant criminal, civil and administrative penalties, damages, fines, imprisonment, contractual damages, reputational harm, diminished profits and future earnings, additional reporting requirements and/or oversight if we become subject to a consent decree or similar agreement to resolve allegations of non-compliance with these laws, and the curtailment or restructuring of our operations, any of which could adversely affect our ability to operate our business and our results of operations. To the extent that we collect or otherwise process personal information, we may be subject to privacy or data protection laws that are in effect in such third countries. Regulation and Procedures Governing Approval of Medicinal Products in Europe In order to market any medicinal product outside of the U.S., a company must also comply with numerous and varying regulatory requirements to generate relevant data for the purpose of establishing its quality, safety and efficacy. There are specific rules governing, among other things, clinical trials, marketing authorization, commercial sales and distribution of products. Regardless of the product approval status in the U.S., an applicant will need to obtain the necessary approvals granted by the comparable foreign regulatory authorities before it can commence clinical trials or marketing of a medicinal product in those countries or jurisdictions. 49 Table of Contents The processes governing approval of medicinal products in the EU and UK generally adopt a similar approach to that applied in the U.S. They entail satisfactory completion of preclinical studies and adequate and well-controlled clinical trials to establish the safety and efficacy of the product for each proposed indication. Data should be generated to demonstrate that a drug substance and a drug product can be manufactured and controlled according to the pre-specified quality standards. The data relating to quality, preclinical testing and clinical trials should be submitted to the relevant competent authorities in a marketing authorization application (“MAA”) for regulatory review in order to determine whether a marketing authorization can be granted. Even if a marketing authorization has been granted, there is a need to obtain a pricing and reimbursement decision before a new medicinal product can be marketed and sold in the EU and/or the UK (as applicable). Clinical Trial Approval Pursuant to the currently applicable Regulation (EU) No 536/2014 (CTR) and Directive 2005/28/EC on GCP, an applicant must obtain approval from the national competent authority of an EU member state in which the clinical trial is to be conducted, or in multiple member states if the clinical trial is to be conducted in a number of member states. Furthermore, the applicant can only start a clinical trial at a specific site after a research ethics committee has issued a favorable opinion. The clinical trial application must be accompanied by an investigational medicinal product dossier with supporting information prescribed by the CTR and corresponding national laws of the member states. All suspected unexpected serious adverse reactions to the investigational medicinal product that occur during the clinical trial have to be reported to the national competent authorities and research ethics committees of the member state where they occurred. Pursuant to the CTR, a sponsor must submit a single application for a new clinical trial authorization through a centralized EU clinical trials portal called the Clinical Trials Information System (“CTIS”). One national competent authority (from the reporting EU member state selected by the applicant) takes the lead in validating and evaluating the application, as well as consulting and coordinating with the other concerned member states in which the clinical trial is to be conducted. If an application is rejected, it may be amended and resubmitted through CTIS. A concerned member state may in limited circumstances declare an “opt-out” from an approval and prevent the clinical trial from being conducted in that member state. By January 31, 2025, all ongoing trials approved under the CTD must comply with the CTR and information relating to such clinical trials must be recorded in CTIS. The CTR aims to streamline and simplify the rules on safety reporting, and introduces enhanced transparency requirements such as mandatory submission of a summary of the clinical trial results to the CTIS. The UK formally left the EU on January 31, 2020, under the terms of the Agreement on the withdrawal of the UK of Great Britain and Northern Ireland from the EU and the European Atomic Energy Community (the EU-UK Withdrawal Agreement). Despite this, EU law continued to apply in the UK until the expiry of the transition period on 31 December 2020. Following the UK’s departure from the EU, the UK and the EU entered into a trade and cooperation agreement (“TCA”), which includes specific provisions concerning pharmaceuticals (such as the mutual recognition of cGMP inspections of manufacturing facilities for medicinal products and cGMP documents issued), but which does not provide for wholesale mutual recognition of UK and EU pharmaceutical regulations. At the point that the transition period expired, the Northern Ireland Protocol, which is contained in the EU-UK Withdrawal Agreement, took effect. The Northern Ireland Protocol makes certain provisions of EU law, including several concerning medicinal products, applicable in Northern Ireland. This position has recently been revised via the Windsor Framework. Under the Windsor Framework, from January 1, 2025, all new medicinal products for the UK market will be authorized by the UK’s Medicines and Healthcare products Regulatory Agency (“MHRA”) (see further below). In the UK, clinical trials of medicinal products are primarily governed by the Medicines for Human Use (Clinical Trials) Regulations 2004, as amended (the UK Regulations). The UK Regulations sought to implement the CTD while the UK was a member state of the EU. Since the CTR was not in force in the EU at the time when the UK exited the EU, it was not retained in UK law on exit day under the terms of the European Union (Withdrawal) Act 2018. Following a public consultation which was conducted in early 2022, the UK authorities are in the process of developing legislation which seeks to improve and strengthen the clinical trials regulatory regime in the UK. The extent to which the regulation of clinical trials in the UK will mirror the CTR is unknown at present. 50 Table of Contents Accelerated Assessment Pathways The EU’s Priority Medicines (“PRIME”) scheme is intended to encourage drug development in areas of unmet medical need and facilitates accelerated assessment of medicinal products representing substantial innovation reviewed under the centralized procedure. Eligible products must target conditions for which there is an unmet medical need (there is no satisfactory method of diagnosis, prevention or treatment in the EEA or, if there is, the new medicine will bring a major therapeutic advantage) and they must demonstrate the potential to address the unmet medical need by, for example, introducing new methods of therapy or improving existing ones. Products from small- and medium-sized enterprises may qualify for earlier entry into the PRIME scheme. Many benefits accrue to sponsors of therapeutic candidates with PRIME designation, including but not limited to, early and proactive regulatory dialogue with the European Medicines Agency (“EMA”), frequent discussions on clinical trial designs and other development program elements, and accelerated MAA assessment once a dossier has been submitted. Importantly, an EMA contact and rapporteur from the Committee for Human Medicinal Products (“CHMP”), or Committee for Advanced Therapies are appointed early in the PRIME scheme facilitating increased understanding of the product at the EMA’s Committee level. A kick-off meeting initiates these relationships and includes a team of multidisciplinary experts at the EMA to provide guidance on the overall development and regulatory strategies. Where, during the course of development, a medicine no longer meets the eligibility criteria, support under the PRIME scheme may be withdrawn. The UK’s Innovative Licensing and Access Pathway (“ILAP”) aims to accelerate the time to market of innovative medicinal products. It is open to both commercial and non-commercial applicants, who are based in the UK or global, and who are developing medicinal products which include products containing new chemical entities, biological medicinal products, new indications and repurposed medicinal products. It comprises of an Innovation Passport designation and a Target Development Profile, and provides applicants with access to a toolkit to support all stages of the design, development and approvals process. The major benefit of the ILAP scheme is that it provides applicants with opportunities for enhanced regulatory and stakeholder input during the development of their medicinal products. Marketing Authorization To obtain a marketing authorization for a medicinal product under the EU regulatory system, an applicant must submit an MAA, either under a centralized procedure administered by the EMA or one of the procedures administered by competent authorities in EU member states (decentralized procedure, national procedure, or mutual recognition procedure). A marketing authorization may be granted only to an applicant established in the EU. Regulation (EC) No 1901/2006 provides that prior to obtaining a marketing authorization in the EU, an applicant must demonstrate compliance with all measures included in an EMA-approved Pediatric Investigation Plan (“PIP”), covering all subsets of the pediatric population, unless the EMA has granted a product-specific waiver, class waiver or a deferral for one or more of the measures included in the PIP. The Paediatric Committee of the EMA (“PDCO”), may grant deferrals for some medicines, allowing a company to delay development of the medicine for children until there is enough information to demonstrate its effectiveness and safety in adults. The PDCO may also grant waivers when development of a medicine for children is not needed or is not appropriate, such as for diseases that only affect the elderly population. An application for marketing authorization or a variation or a variation or a line-extension which is accompanied by the pediatric clinical trials conducted in accordance with the PIP (even where such results are negative) are eligible for a six months extension of their supplementary protection certificate. In the case of orphan medicinal products, a two-year extension of the orphan market exclusivity may be available. This pediatric reward is not automatically available and is subject to the EMA or the relevant national competent authorities confirming compliance with the agreed PIP that may require an opinion to be given by the EMA’s Pediatric Committee. The centralized procedure provides for the grant of a single marketing authorization by the European Commission that is valid for all EU member states, as well as the additional member states of the EEA (Norway, Iceland and Liechtenstein). Pursuant to Regulation (EC) No 726/2004, the centralized procedure is compulsory for specific products, including for medicines developed by means of certain biotechnological processes (including, recombinant DNA technology, controlled expression of genes coding for biologically active proteins in prokaryotes and eukaryotes including transformed mammalian cells, and hybridoma and monoclonal antibody methods), products designated as orphan medicinal products, advanced therapy medicinal products (gene-therapy, somatic cell-therapy or tissue-engineered medicines) and products containing a new active substance indicated for the treatment of certain diseases, including products for the treatment of 51 Table of Contents cancer, HIV / AIDS, neurodegenerative disorders, diabetes, auto-immune diseases and other immune dysfunctions, and viral diseases. The centralized procedure is optional for products containing a new active substance which was not authorized in the EU on May 20, 2004, or for products that constitute a significant therapeutic, scientific or technical innovation or which are in the interest of public health in the EU. An applicant for the centralized MA must demonstrate the quality, safety and efficacy of their products to the EMA for an opinion to be adopted regarding the approvability of the MAA. The European Commission grants or refuses marketing authorization in light of the opinion delivered by the EMA. Under the centralized procedure, the CHMP established within the EMA is responsible for conducting an initial assessment of a medicinal product. The maximum timeframe for the evaluation of an MAA is 210 days, excluding clock stops when additional information or written or oral explanation is to be provided by the applicant in response to questions of the CHMP. Clock stops may extend the timeframe of evaluation of an MAA considerably beyond 210 days. Where the CHMP gives a positive opinion, the EMA provides the opinion together with supporting documentation to the European Commission, who make the final decision to grant a marketing authorization, which is issued ordinarily within 67 days of receipt of the EMA’s recommendation. Accelerated evaluation may be granted by the CHMP in exceptional cases, when a medicinal product is of major interest from the point of view of public health and, in particular, from the viewpoint of therapeutic innovation. If the CHMP accepts such a request, the time limit of 210 days will be reduced to 150 days (excluding clock stops), but it is possible that the CHMP may revert to the standard time limit for the centralized procedure if it determines that it is no longer appropriate to conduct an accelerated assessment. National marketing authorizations, which are issued by the national competent authorities of the member states of the EEA and only cover their respective territory, are available for products not falling within the mandatory scope of the centralized procedure. Where a medicinal product has already been authorized for marketing in a member state of the EEA, this national authorization can be recognized in other member states through the mutual recognition procedure. If the product has not received a national authorization in any member state at the time of application, it can be approved simultaneously in two or more member states through the decentralized procedure. For the time being, under the Northern Ireland Protocol, centralized marketing authorizations continue to provide a valid basis for commercializing medicinal products in Northern Ireland. However, centralized marketing authorizations no longer provide a valid basis for the commercialization of medicinal products in Great Britain. Pursuant to the Windsor Framework, from January 1, 2025, all new medicinal products for the UK market will be authorized by the MHRA. In this regard, the MHRA will grant a single UK-wide marketing authorization for all medicinal products intended for sale in the UK, enabling medicinal products to be sold in a single pack and under a single authorization throughout the UK. Following its departure from the EU, the UK has introduced changes to its national licensing procedures, including procedures to prioritize access to new medicines that will benefit patients, ILAP (described above) and new routes of evaluation for novel products and biotechnological products. Notwithstanding that there is no wholesale recognition of EU pharmaceutical legislation under the TCA, and that EU marketing authorizations do not automatically provide a valid basis for the commercialization of medicinal products in Great Britain from January 1, 2024, applicants will be able to request the MHRA to recognize marketing authorizations granted in foreign jurisdictions (including the EU) under a new International Recognition Procedure. Regulatory Data Protection in Europe In the EU and the UK, new chemical entities (including both small molecules and biological medicinal products) and new biological substances approved on the basis of a complete independent data package consisting of quality, preclinical testing results and clinical trial data qualify for eight years of RDP upon grant of a marketing authorization and two years of marketing protection. Data protection prevents generic or biosimilar applicants from referencing the innovator’s preclinical and clinical trial data contained in the MAA dossier of the reference medicinal product when applying for a generic or biosimilar marketing authorization, for a period of eight years from the date on which the reference product was first authorized in the EU. During the two-year period of marketing protection, a generic or biosimilar MAA can be submitted, and the innovator’s data may be referenced. Even if a generic or biosimilar medicinal product is approved, it cannot be marketed until the expiration of the marketing protection. The ten-year protection period can be extended to a maximum of eleven years if, during the first eight years of those ten years, the marketing authorization holder obtains an authorization for one or more new therapeutic indications which, during the scientific evaluation prior to authorization, is 52 Table of Contents held to bring a significant clinical benefit in comparison with existing therapies. Even if a compound is considered to be a new chemical or a new biological entity so that the innovator gains the prescribed period of data protection, another company may market another version of the medicinal product if such company obtained marketing authorization based on an MAA with a complete and independent data package consisting of pharmaceutical and preclinical testing results and clinical trial data. Patent Term Extensions in the EU and Other Jurisdictions The EU also provides for patent term extension through SPCs which aim to offset the loss of patent protection for pharmaceutical products arising from the lengthy testing and clinical trials required to obtain an MA. The rules and requirements for obtaining a SPC are similar to those in the U.S. An SPC may extend the term of a basic patent for up to five years after its originally scheduled expiration date in order to provide up to a maximum of fifteen years of exclusivity from the time the medicinal product in question first obtains an MA for it to be placed on the market. As mentioned above, in certain circumstances, these periods may be extended for six additional months if pediatric exclusivity is obtained; and in the case of orphan medicinal products, a two-year extension of the orphan market exclusivity may be available. Although SPCs are available throughout the EU, holders must apply the patent term extension on a country-by-country basis. Similar patent term extension rights exist in certain other foreign jurisdictions outside the EU. Orphan Drug Designation and Exclusivity Regulation (EC) No 141/2000 and Regulation (EC) No. 847/2000 provide that a medicinal product can be designated as an orphan medicinal product by the European Commission, upon satisfactory scientific assessment by the EMA’s Committee for Orphan Medicinal Products (“COMP”), if the sponsor can establish: (1) that the product is intended for the diagnosis, prevention or treatment of a life-threatening or chronically debilitating condition, where either (i) such condition affects not more than five in ten thousand persons in the EU when the application is made, or (ii) without incentives it is unlikely that the marketing of the drug in the EU would generate sufficient return to justify the necessary investment in its development, and (2) that there exists no satisfactory method of diagnosis, prevention or treatment of the condition in question that has been authorized in the EU or, if such method exists, the drug will be of significant benefit to those affected by that condition. In the UK, the MHRA conducts an equivalent assessment, against criteria which have been tailored for the UK population. The COMP is required to re-assess the granted orphan designation at the time of marketing authorization grant to ensure that it continues to meet the criteria for the designation to be maintained. Otherwise, the orphan designation can be revoked. In relation to the UK, the MHRA does not grant orphan designations during the development of the medicinal product. Instead, the MHRA will decide whether the criteria are satisfied at the point of marketing authorization grant. An orphan drug designation provides a number of benefits, including fee reductions, fee waivers, protocol assistance (as a type of scientific advice specific for orphan medicinal products) and the possibility to apply for a centralized EU marketing authorization. Marketing authorization for an orphan medicinal product benefits from a ten-year period of market exclusivity. During this period of market exclusivity, the European Commission, national competent authorities of the EU member states may only grant marketing authorization to a “similar medicinal product” for the same therapeutic indication if: (i) a second applicant can establish that its medicinal product, although similar to the authorized product, is safer, more effective or otherwise clinically superior; (ii) the marketing authorization holder for the authorized product consents to a second orphan medicinal product application; or (iii) the marketing authorization holder for the authorized product cannot supply enough orphan medicinal product. A “similar medicinal product” is defined as a medicinal product containing a similar active substance or substances as contained in an authorized orphan medicinal product, and which is intended for the same therapeutic indication. The period of marketing protection for the authorized therapeutic indication may, however, be reduced to six years if, at the end of the fifth year, it is established that the product no longer meets the criteria for orphan drug designation because, for example, the product is sufficiently profitable not to justify market exclusivity. Orphan medicinal product designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process. Following the UK’s exit from the EU, the MHRA continues to apply the same orphan market exclusivity framework as the EU. 53 Table of Contents Periods of Authorization and Renewals A marketing authorization is valid for five years, in principle, and it may be renewed indefinitely after five years on the basis of a reevaluation of the risk-benefit balance by the EMA, the competent authority of the authorizing member state, or the MHRA. To that end, the marketing authorization holder must provide the EMA, the relevant national competent authority, or the MHRA with a consolidated version of the file in respect of quality, safety and efficacy, including all variations introduced since the marketing authorization was granted, at least six months before the marketing authorization expiry date. Once renewed, the marketing authorization is valid for an unlimited period, unless the European Commission, the relevant national competent authority, or the MHRA decides, on justified grounds relating to pharmacovigilance, to proceed with one additional five-year renewal period. Any marketing authorization ceases to be valid if it is not followed by the placement of the medicinal product on the EU market (in the case of the centralized procedure), on the market of the authorizing member state (in the case of a national procedure), or the UK market (as applicable), within three years after grant of such an authorization. Regulatory Requirements After Marketing Authorization Following approval, the holder of the marketing authorization is required to comply with a range of requirements applicable to the manufacturing, marketing, promotion and sale of the medicinal product, and must adhere in strict compliance with the applicable EU laws, regulations and guidance. These include compliance with stringent pharmacovigilance rules, pursuant to which post-authorization studies and additional monitoring obligations can be imposed. In addition, manufacture and control must also be conducted in strict compliance with cGMP requirements and comparable requirements of other regulatory bodies in the EU and UK. cGMP requirements apply to the methods, facilities and controls used in manufacturing, processing and packing of drugs against the quality standards appropriate to the intended use of a medicinal product and as required by the marketing authorization, clinical trial authorization or product specification. Much like the federal healthcare program anti-kickback law in the U.S., the provision of benefits or advantages to physicians to induce or encourage the prescription, recommendation, endorsement, purchase, supply, order or use of medicinal products is also prohibited in the EU and the UK. The provision of benefits or advantages to induce or reward improper performance generally is governed by the national anti-bribery laws of EU member states and the Bribery Act 2010 in the UK. Infringement of these laws could result in substantial fines and imprisonment. Applicable law in Europe further provides that, where medicinal products are being promoted to persons qualified to prescribe or supply them, no gifts, pecuniary advantages or benefits in kind may be supplied, offered or promised to such persons unless they are inexpensive and relevant to the practice of medicine or pharmacy. Pursuant to national laws, industry codes or professional codes of conduct payments made to physicians in certain EU member states and the UK must be publicly disclosed. Moreover, agreements with physicians often must be the subject of prior notification and approval by the physician’s employer, his or her competent professional organization and/or the regulatory authorities of the individual EU member states, or the UK (as applicable). Failure to comply with these requirements could result in reputational risk, public reprimands, administrative penalties, fines or imprisonment. The advertising and promotion of medicinal products is also subject to laws concerning promotion of medicinal products, interactions with physicians, misleading and comparative advertising and unfair commercial practices. All advertising and promotional activities for the product must be consistent with the approved summary of product characteristics, and therefore all off-label promotion is prohibited. Direct-to-consumer advertising of prescription medicines is also prohibited in the EU and the UK. Although general requirements for advertising and promotion of medicinal products are established under Directive 2001/83/EC, which was transposed into national law in the UK via the Human Medicines Regulations 2012, the details are governed by regulations in each European jurisdiction and can differ from one country to another. General Data Protection Regulation The processing of personal data regarding individuals in the EU, including personal health data, is regulated by Regulation (EU) 2016/679, which took effect on May 25, 2018. The GDPR is wide-ranging in scope and imposes numerous requirements on companies that process personal data, including requirements relating to processing health and other sensitive data, obtaining consent of the individuals to whom the personal data relates, providing information to individuals 54 Table of Contents regarding data processing activities, implementing safeguards to protect the security and confidentiality of personal data, providing notification of data breaches and taking certain measures when engaging third-party processors. The GDPR also imposes strict rules on the transfer of personal data to countries outside the EU, including the U.S., and permits data protection authorities to impose large penalties for violations of the GDPR, including potential fines of up to €20 million or 4% of annual global revenues, whichever is greater. The GDPR also confers a private right of action on data subjects and consumer associations to lodge complaints with supervisory authorities, seek judicial remedies and obtain compensation for damages resulting from violations of the GDPR. Compliance with the GDPR will be a rigorous and time-intensive process that may increase the cost of doing business or require us to change our business practices to ensure full compliance. As of January 1, 2021, the UK’s European Union (Withdrawal) Act 2018 incorporated the GDPR (as it existed on December 31, 2020 but subject to certain UK specific amendments) into UK law, referred to as the UK GDPR. The UK GDPR and the UK Data Protection Act 2018 set out the UK’s data protection regime, which is independent from but aligned to the EU’s data protection regime. Non-compliance with the UK GDPR may result in monetary penalties of up to £17.5 million or 4% of worldwide revenue, whichever is higher. Coverage and Reimbursement Significant uncertainty exists as to the coverage and reimbursement status of any product candidates for which we may seek regulatory approval by the FDA or other government authorities. In the U.S. and markets in other countries, patients generally rely on third-party payors to reimburse all or part of the costs associated with their treatment. Adequate coverage and reimbursement from governmental healthcare programs, such as Medicare and Medicaid, and commercial payors is critical to new product acceptance. Our ability to successfully commercialize our product candidates will depend in part on the extent to which coverage and adequate reimbursement for these products and related treatments will be available from government health authorities or programs, private health insurers and other organizations. Even if coverage is provided, the approved reimbursement amount may not be high enough to allow us to establish or maintain pricing sufficient to realize a sufficient return on our investment. Government authorities and other third-party payors, such as private health insurers and health maintenance organizations, decide which medications they will pay for and establish reimbursement levels. Additionally, coverage and reimbursement for drug products can differ significantly from payor to payor. One third-party payor’s decision to cover a particular drug product or service does not ensure that other payors will also provide coverage for the drug product, or will provide coverage at an adequate reimbursement rate. Coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more product candidates for which we receive regulatory approval from one or more third party payors, less favorable coverage policies and reimbursement rates may be implemented in the future. Additionally, if a companion diagnostic test is developed for use with a drug product, any coverage and reimbursement for that test would be separate and apart from the coverage and reimbursement sought for such product. A lack of coverage or adequate reimbursement for such a test could adversely affect access to a drug product. Within the U.S., third-party payors are increasingly seeking to control drug costs by examining the cost-effectiveness of new products and services in addition to their safety and efficacy; managing drug utilization and challenging the price of drugs. To obtain or maintain coverage and reimbursement for any future product, we may need to conduct expensive pharmacoeconomic studies to demonstrate the medical necessity and cost-effectiveness of our product. These studies will be in addition to the studies required to obtain regulatory approvals. Third-party payors may limit coverage of product by, for example, only covering specific products on an approved list, or formulary, which might not include all of the FDA-approved products for a particular indication. Some third-party payors may manage utilization of a particular product by requiring pre-approval (known as “prior authorization”) for coverage of particular prescriptions (to allow the payor to assess medical necessity) or otherwise restricting coverage of a product even if used consistent with its approved indication. Manufacturers of marketed drugs may be required to provide discounts or rebates under government healthcare programs or to certain government and private purchasers in order to obtain coverage under federal healthcare programs such as Medicaid. More generally, price concessions may need to be offered to third party payors to obtain favorable coverage or to purchasers to achieve sales. Arrangements with third party payors or purchasers may include value-based arrangements under which the amount paid for products depends on the performance of the product. Net prices for drugs may be further reduced by mandatory discounts or rebates required by government healthcare programs or private payors 55 Table of Contents and by any future relaxation of laws that presently restrict imports of drugs from countries where they may be sold at lower prices than in the U.S. In addition, in some foreign countries, the proposed pricing for a drug must be approved before it may be lawfully marketed. The requirements governing drug pricing vary widely from country to country. For example, the EU provides options for its member states to restrict the range of medicinal products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. To obtain reimbursement or pricing approval, some of these countries may require the completion of clinical trials that compare the cost effectiveness of a particular medicinal product candidate to currently available therapies. A member state may approve a specific price for the medicinal product or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the medicinal product on the market. There can be no assurance that any country that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our product candidates. Historically, products launched in the EU do not follow price structures of the U.S. and generally prices tend to be significantly lower. Healthcare Reform Payors, whether domestic or foreign, or governmental or private, are developing increasingly sophisticated methods of controlling healthcare costs and those methods are not always specifically adapted for therapies addressing rare diseases such as those we are developing. In both the U.S. and certain foreign jurisdictions, there have been a number of legislative and regulatory changes to the healthcare system that could impact our ability to sell our product candidates profitably if and when approved for marketing. In particular, in 2010, the ACA was enacted, which, among other things, subjected biologic products to potential competition by lower-cost biosimilars; addressed a new methodology by which rebates owed by manufacturers under the Medicaid Drug Rebate Program are calculated for drugs that are inhaled, infused, instilled, implanted or injected; increased the minimum Medicaid rebates owed by most manufacturers under the Medicaid Drug Rebate Program; extended the Medicaid Drug Rebate program to utilization of prescriptions of individuals enrolled in Medicaid managed care organizations; subjected manufacturers to new annual fees and taxes for certain branded prescription drugs; created a new Medicare Part D coverage gap discount program, in which manufacturers must agree to offer point-of-sale discounts off negotiated prices of applicable brand drugs to eligible beneficiaries during their coverage gap period, as a condition for the manufacturer’s outpatient drugs to be covered under Medicare Part D. More generally, the ACA expanded healthcare coverage through Medicaid expansion and the implementation of the “individual mandate” for health insurance coverage. Beyond the ACA, there have been ongoing healthcare reform efforts. Drug pricing and payment reform was a focus of the Trump administration and has been a focus of the Biden administration. For example, federal legislation enacted in 2021 eliminates the statutory cap on Medicaid drug rebate program rebates (currently set at 100% of a drug’s “average manufacturer price”), effective January 1, 2024. As another example, the IRA, includes a number of changes intended to address rising prescription drug prices in Medicare Parts B and D. These changes include caps on Medicare Part D out-of-pocket costs, Medicare Part B and Part D drug price inflation rebates, a new Medicare Part D manufacturer discount drug program (replacing the ACA Medicare Part D coverage gap discount program) and a drug price negotiation program for certain high spend Medicare Part B and D drugs (with the first list of drugs announced in 2023). The IRA changes have varying implementation dates that start in 2022. On August 29, 2023, HHS announced the list of the first ten drugs that will be subject to price negotiations. The focus on healthcare reform, including reform of drug pricing and payment, has continued in the wake of the IRA. For example, in 2022, subsequent to the enactment of the IRA, the Biden administration released an executive order directing the HHS to report on how the Center for Medicare and Medicaid Innovation (“CMMI”) could be leveraged to test new models for lowering drug costs for Medicare and Medicaid beneficiaries. The report was issued in 2023 and proposed various models that CMMI is currently developing which seek to lower the cost of drugs, promote accessibility and improve quality of care. Further, in December 2023, the Biden administration announced an initiative to control the price of prescription drugs through the use of march-in rights under the Bayh-Dole Act (which allow the government, in specified circumstances, to grant or require a patent-holder of technology funded by the federal government to grant a license to certain third parties). The announcement was followed by publication of Draft Interagency Guidance Framework for Considering the Exercise of March-In Rights which for the first time includes the price of a product as one factor an agency can use when deciding to exercise march-in rights. While march-in rights have not previously been exercised, given these actions, there can be no certainty that such rights will not be exercised in the future. 56 Table of Contents Healthcare reform efforts have been and may continue to be subject to scrutiny and legal challenge. For example, with respect to the ACA, tax reform legislation was enacted that eliminated the tax penalty established for individuals who do not maintain mandated health insurance coverage beginning in 2019 and, in 2021, the U.S. Supreme Court dismissed the latest judicial challenge to the ACA brought by several states without specifically ruling on the constitutionality of the ACA. As another example, revisions to regulations under the federal anti-kickback statute would remove protection for traditional Medicare Part D discounts offered by pharmaceutical manufacturers to pharmacy benefit managers and health plans. Pursuant to court order, the removal was delayed and recent legislation imposed a moratorium on implementation of the rule until January 2032. As another example, the IRA drug price negotiation program has been challenged in litigation filed by various pharmaceutical manufacturers and industry groups. There have also been efforts by federal and state government officials or legislators to implement measures to regulate prices or payment for pharmaceutical products, including legislation on drug importation. For example, on January 5, 2024, the FDA approved Florida’s Section 804 Importation Program (SIP) proposal to import certain drugs from Canada for specific state healthcare programs. It is unclear how this program will be implemented, including which drugs will be chosen, and whether it will be subject to legal challenges in the U.S. or Canada. Other states have also submitted Section 804 Importation Program (“SIP”) proposals that are pending review by the FDA. Any such approved importation plans, when implemented, may result in lower drug prices for products covered by those programs. Recently, there has been considerable public and government scrutiny of pharmaceutical pricing and proposals to address the perceived high cost of pharmaceuticals. There have also been recent state legislative efforts to address drug costs, which generally have focused on increasing transparency around drug costs or limiting drug prices. General legislative cost control measures may also affect reimbursement for our product candidates. The Budget Control Act, as amended, resulted in the imposition of reductions in Medicare (but not Medicaid) payments to providers in 2013 that remain in effect through 2032 unless additional Congressional action is taken. Any significant spending reductions affecting Medicare, Medicaid or other publicly funded or subsidized health programs that may be implemented and/or any significant taxes or fees that may be imposed on us could have an adverse impact on our results of operations. Adoption of new legislation at the federal or state level could affect demand for, or pricing of, any future products if approved for sale. We cannot, however, predict the ultimate content, timing or effect of any federal and state reform efforts. There is no assurance that federal or state healthcare reform will not adversely affect our future business and financial results. Other Healthcare Laws Pharmaceutical companies are subject to additional healthcare regulation and enforcement by the federal government and by authorities in the states and foreign jurisdictions in which they conduct their business that may constrain how we conduct our business, including the financial arrangements and relationships through which we research, as well as sell, market and distribute any products for which we obtain marketing authorization. Restrictions under applicable federal and state healthcare laws and regulations, some of which will apply only if and when we receive marketing approval for a product candidate, include the following: ● federal healthcare program anti-kickback law, which prohibits, among other things, persons from soliciting, receiving or providing remuneration, directly or indirectly, to induce either the referral of an individual for an item or service or the purchasing or ordering of a good or service, for which payment may be made under federal healthcare programs such as Medicare and Medicaid; ● federal false claims, false statements and civil monetary penalties laws which prohibit, among other activities, any person from knowingly presenting, or causing to be presented, a false claim for payment of government funds or knowingly making, or causing to be made, a false statement to get a false claim paid and may be implicated if claims are submitted that result from a violation of the federal anti-kickback statute; ● HIPAA, which, in addition to privacy protections applicable to healthcare providers and other entities, prohibits executing a scheme to defraud any healthcare benefit program or making false statements relating to healthcare matters; 57 Table of Contents ● the FDCA, which among other things, strictly regulates drug marketing, prohibits manufacturers from marketing such products for off-label use and regulates the distribution of samples; ● federal laws that require pharmaceutical manufacturers to report certain calculated product prices to the government or provide certain discounts or rebates to government authorities or private entities, often as a condition of reimbursement under government healthcare programs; ● the so-called “federal sunshine” law, which requires pharmaceutical and medical device companies to monitor and report certain financial interactions with physicians, certain non-physician practitioners and teaching hospitals to the federal government for re-disclosure to the public; ● the U.S. Foreign Corrupt Practices Act of 1977, as amended, which prohibits, among other things, U.S. companies and their employees and agents from authorizing, promising, offering, or providing, directly or indirectly, corrupt or improper payments or anything else of value to foreign government officials, employees of public international organizations and foreign government owned or affiliated entities, candidates for foreign political office, and foreign political parties or officials thereof; and ● analogous state and foreign laws and regulations, such as state anti-bribery, anti-kickback and false claims laws, which may apply to healthcare items or services that are reimbursed by non-governmental third-party payors, including private insurers. Some state laws require pharmaceutical companies to comply with specific compliance standards, restrict financial interactions between pharmaceutical companies and healthcare providers or require pharmaceutical companies to report information related to payments to healthcare providers or marketing expenditures. Other state laws may require pharmaceutical companies to file reports relating to pricing and marketing information, and state and local laws may require registration of pharmaceutical sales representatives. Efforts to ensure that our business arrangements with third parties comply with applicable healthcare laws and regulations will involve substantial costs. Given the breadth of the laws and regulations, limited guidance for certain laws and regulations and evolving government interpretations of the laws and regulations, governmental authorities may possibly conclude that our business practices may not comply with healthcare laws and regulations. If our operations are found to be in violation of any of the laws described above or any other government regulations that apply to us, we may be subject to penalties, including significant civil and criminal penalties, damages, fines, exclusion from participation in government healthcare programs, such as Medicare and Medicaid, imprisonment, and the curtailment or restructuring of our operations, any of which could adversely affect our business, financial condition, results of operations, and prospects. Employees and Human Capital Resources As of February 28, 2025, we had 130 full-time employees, consisting of clinical, scientific, development, medical affairs, technical operations, regulatory, finance, legal and operational personnel. None of our employees is represented by labor unions or subject to a collective bargaining agreement. Our personnel outside of the U.S. are subject to employment contracts which contain customary notice periods. We consider our relationship with our employees to be good. Of our 130 full-time employees as of February 28, 2025, 14 were located in China and consisted of clinical, technical operations, regulatory, finance and human resources personnel. Our China-based employees support clinical operations and regulatory matters related to obexelimab in the Asia-Pacific region and technical operations, with all functions in China reporting to management in the U.S. We also have dedicated medical and commercial personnel located in Europe to advance our obexelimab strategy in that region. We recognize that our continued ability to attract, retain, and motivate exceptional employees is vital to ensuring our long-term competitive advantage. Our employees are critical to our long-term success and are essential to helping us meet our goals. Among other things, we support and incentivize our employees in the following ways: ● Talent development, compensation, and retention : Our human capital resources objectives include, as applicable, identifying, recruiting, retaining, incentivizing and integrating our existing and future employees. Our compensation program is designed to retain, motivate and attract highly qualified employees. Accordingly, we 58 Table of Contents use a mix of competitive base salary, cash-based annual incentive compensation, performance-based equity compensation awards and other employee benefits. ● Health and safety : We value the health and safety of our employees and provide comprehensive insurance benefits, an employee assistance program, paid holidays, a personal time-off program, and other benefits which are intended to assist employees to manage their well-being. ● Inclusion and diversity : We are committed to efforts to increase diversity and foster an inclusive professional environment that supports our workforce. Corporate and Other Information We incorporated in November 2019 as Zenas BioPharma (Cayman) Limited, an exempted company incorporated in the Cayman Islands with limited liability, and commenced operations in 2020. On August 2, 2023, the Company (then known as Zenas BioPharma (Cayman) Limited) de-registered from the Cayman Islands and registered by way of continuation in the State of Delaware. Our principal executive offices are located at 852 Winter Street, Suite 250, Waltham MA 02451, and our telephone number at that address is (857) 271-2954. On September 16, 2024, the Company completed its initial public offering (“IPO”), in which the Company issued and sold 15,220,588 shares of its common stock, including 1,985,294 shares pursuant to the full exercise of the underwriters’ option to purchase additional shares, at a public offering price of $17.00 per share, for aggregate gross proceeds of $258.7 million. The Company received approximately $234.3 million in net proceeds after deducting underwriting discounts, commissions and other offering expenses. Available Information Our Internet address is www.zenasbio.com. Our website and the information contained on, or that can be accessed through, the website will not be deemed to be incorporated by reference in, and are not considered part of, this Annual Report on Form 10-K. Our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, including exhibits, proxy and information statements and amendments to those reports filed or furnished pursuant to Sections 13(a), 14, and 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) are available through the “Investor & Media Relations” portion of our website free of charge as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. In addition, our filings with the SEC may be accessed through the SEC’s Electronic Data Gathering, Analysis and Retrieval system at http://www.sec.gov. All statements made in any of our securities filings, including all forward-looking statements or information, are made as of the date of the document in which the statement is included, and we do not assume or undertake any obligation to update any of those statements or documents unless we are required to do so by law. ​ ​ 59 Table of Contents Item 1A. Risk Factors Investors should carefully consider the risks described below, together with the other information contained in this Annual Report, including in the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and in our audited consolidated financial statements and the related notes contained in this Annual Report. The events discussed below may occur and adversely impact our business, financial condition, results of operations and prospects, which may cause the trading price of our common stock to decline. These risks and uncertainties described below are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently believe to be immaterial may also affect our business. See “Special Note Regarding Forward-Looking Statements.” Risks Related to Our Financial Position and Need for Capital We are a clinical stage biopharma company with a limited operating history and no products approved for commercial sale; we have incurred substantial losses since our inception, and we anticipate incurring substantial and increasing losses for the foreseeable future. We are a clinical stage biopharma company with a limited operating history on which to base an investment decision. We have no product candidates approved for commercial sale in any country and have not generated any revenue from sales of products. Biopharmaceutical product development is a highly speculative undertaking, involving substantial upfront capital expenditure and significant risk. Any product candidate may fail to demonstrate adequate efficacy or an acceptable safety profile, gain regulatory approval or become commercially viable, despite substantial investment on development or commercialization. We have incurred, and will continue to incur, significant expenses related to the clinical development of our product candidates and ongoing operations. For the year ended December 31, 2024, we reported a net loss of $157.0 million. As of December 31, 2024, we had accumulated deficit of $387.4 million, which included non-cash charges for stock-based compensation and acquisition and development expenses. We expect to continue to incur significant losses for the foreseeable future, and we expect these losses to increase as we advance the development of our product candidates. We may also encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. The size of our future net losses will depend, in part, on the rate that our expenses increase and our ability to generate revenue. Our prior losses and expected future losses have had and will continue to have an adverse effect on our stockholders’ equity and our working capital. We anticipate that our expenses will increase substantially if, and as, we: ● continue clinical development of obexelimab and our other programs; ● advance our obexelimab program and our other product candidates through preclinical development and clinical trials; ● identify additional product candidates and acquire rights from third parties to those product candidates through licenses or acquisitions and conduct development activities, including preclinical studies and clinical trials; ● make royalty, milestone or other payments under current, and any future, license or collaboration agreements; ● procure the manufacturing of preclinical, clinical and commercial supply of our current or any future product candidates; ● seek marketing regulatory approvals for our current or any future product candidates that successfully complete clinical trials; ● commercialize our current or any future product candidates, if approved; 60 Table of Contents ● take steps toward our goal of being an integrated biopharma company capable of supporting commercial activities, including establishing sales, marketing and distribution infrastructure; ● attract, hire and retain qualified clinical, scientific, operations and management personnel; ● seek to continue to develop, maintain and defend our intellectual property portfolio, including against third-party interference, infringement and other intellectual property claims, if any; ● add and maintain operational, financial and information management systems; ● attempt to address any competing therapies and market developments; ● experience delays in our preclinical studies, clinical trials or regulatory approval for our current or any future product candidates, including with respect to failed studies, inconclusive results, safety issues or other regulatory challenges; ● establish agreements with contract research organizations (“CROs”) and contract manufacturing organizations (“ CMOs”); and ● incur additional costs associated with being a public company, including audit, legal, regulatory and tax-related services associated with maintaining compliance with an exchange listing and the Securities and Exchange Commission (the “SEC”) requirements, director and officer insurance premiums and investor relations costs. Even if we succeed in commercializing one or more product candidates, we expect to incur substantial expenditures to develop and market additional product candidates. We will require substantial additional financing to achieve our goals, and failure to obtain additional capital when needed, or on acceptable terms, would cause us to delay, limit, reduce or terminate our product development efforts. The development of biopharmaceutical product candidates, including conducting preclinical studies and clinical trials, is a time consuming, capital-intensive and uncertain process. Our operations have consumed substantial amounts of cash since inception. We expect our expenses to substantially increase in connection with our ongoing and future activities. If we obtain regulatory approval for obexelimab or other product candidates, we also expect to incur significant commercialization expenses related to manufacturing, marketing, sales and distribution of such products. Because the outcome of any clinical trial or preclinical study is uncertain, we cannot reliably estimate the actual amount of capital necessary to successfully complete the development and commercialization of obexelimab and other product candidates. As of December 31, 2024, we had $350.8 million in cash, cash equivalents and short-term investments. Based upon our current operating plan, we believe that our cash, cash equivalents and investments as of December 31, 2024, will be sufficient to fund our operating expenses and capital expenditure requirements into the fourth quarter of 2026. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect. We expect to attempt to raise additional cash in advance of exhausting our available capital resources. We will not generate revenue from product sales unless and until we successfully complete clinical development and obtain regulatory approval for a product candidate, and we may not ever generate significant revenue or profits. In addition, we expect to incur costs associated with operating as a public company, including significant legal, accounting, investor relations, and other expenses that we did not incur prior to our IPO. If we obtain regulatory approval for a product candidate and do not enter into a third-party commercialization partnership, we expect to incur significant expenses related to developing our commercialization capability to support product sales, marketing, manufacturing and distribution activities. We may also require additional capital to pursue in-licenses or acquisitions of other product candidates. As a result, we expect to incur substantial operating losses and negative operating cash flows for the foreseeable future. 61 Table of Contents Because of the numerous risks and uncertainties associated with research, development and commercialization of product candidates, we are unable to estimate the exact amount of our working capital requirements. Our future funding requirements will depend on, and could increase significantly as a result of, many factors, including: ● the scope, timing and progress of our ongoing obexelimab clinical studies and other research and development activities associated with the development of other and future product candidates; ● the number and scope of preclinical and clinical programs we decide to pursue; ● our ability to maintain our current research and development programs and to establish new programs; ● the timing of and successful patient enrollment in, and the initiation and completion of, clinical trials; ● the successful completion of clinical trials with safety, tolerability and efficacy profiles that are satisfactory to the FDA, or any comparable foreign regulatory authority; ● the timing, receipt and terms of any marketing approvals from applicable regulatory authorities; ● our ability to establish new licensing or collaboration arrangements; ● the performance of our future collaborators, if any; ● our ability to establish arrangements with third-party manufacturers for the commercial supply of products that receive marketing approval, if any; ● development and timely delivery of commercial-grade drug formulations that can be used in our planned clinical trials and for commercialization; ● obtaining, maintaining, defending and enforcing patent claims and other intellectual property rights; ● our ability to hire additional personnel and consultants as our business grows, including additional executive officers and clinical development, regulatory, chemistry, manufacturing and controls, quality and commercial personnel; ● commercializing product candidates, if approved, whether alone or in collaboration with others; ● the costs and timing of establishing or securing sales and marketing capabilities for our product candidates, if approved; ● our ability to achieve sufficient market acceptance, coverage and adequate reimbursement from third-party payors and adequate market share and revenue for any approved products; and ● maintaining a continued acceptable safety profile of the product candidates following approval. We expect that our commercial revenue, if any, will initially be derived from sales of obexelimab, which we do not expect to be commercially available for several years, if ever. Accordingly, we will need to continue to rely on additional financing to achieve our business objectives. Adequate additional financing may not be available to us on acceptable terms, or at all, including as a result of financial and credit market deterioration or instability, market-wide liquidity shortages, geopolitical events or otherwise. If we are unable to raise sufficient additional capital, we would be forced to curtail our planned operations and the pursuit of our growth strategy. 62 Table of Contents Raising additional capital may cause dilution to our stockholders imposing restrictions on our operations or require us to relinquish rights to our product candidates. Until such time, if ever, that we generate substantial product revenue, we expect to finance our cash needs through equity offerings, debt financings or other capital sources, including potential collaborations, licenses and other arrangements. To the extent that we raise additional capital through the sale of equity or convertible debt securities, stockholders’ ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect their rights as a holder of our common stock. Any future debt or preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, selling or licensing our assets, making capital expenditures, declaring dividends or encumbering our assets to secure future indebtedness. Such restrictions could adversely impact our ability to conduct our operations and execute our business plan. If we raise additional funds through future collaborations, licenses and other arrangements, we likely would relinquish valuable rights to our potential future revenue streams or product candidates. We also may grant licenses on terms that may not be favorable to us or that reduce the value of our common stock. If we are unable to raise additional funds through equity or debt financings or other arrangements when needed, or on acceptable terms, we would be required to delay, limit, reduce or terminate our product development efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves. Further, we may not be able to access a portion of our existing cash due to market conditions. If banks and financial institutions with whom we hold accounts enter receivership or become insolvent in the future in response to financial conditions affecting the banking system and financial markets, our ability to access our existing cash may be threatened and could have a material adverse effect on our business and financial condition. Risks Related to Product Candidate Development and Commercialization Clinical development is lengthy and expensive, characterized by uncertain outcomes, with results of earlier studies and trials often failing to predict future trial results or results in other indications of a product candidate. We may incur additional costs or experience delays in completing, or fail to complete, the development and commercialization of our current product candidates or any future product candidates. We face substantial risk of failure with our product candidates and we may fail to receive regulatory approval for any of our product candidates. To obtain the requisite regulatory approvals to commercialize any product candidate, we must demonstrate, through extensive preclinical studies and lengthy, complex and expensive clinical trials, that a product candidate is safe, pure and potent and has a favorable risk-benefit profile. Clinical testing often takes many years to complete, and its outcome is inherently uncertain. The results of preclinical studies and early clinical trials of our product candidates may not predict results of later-stage clinical trials, and results in one indication may not predict results for the same product candidate in another indication. Differences in trial design between early-stage clinical trials and later-stage clinical trials raise challenges for extrapolating the results of earlier clinical trials to later clinical trials. A number of companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to lack of efficacy or unfavorable safety profiles, notwithstanding promising results in earlier trials. Prior to our acquisition of obexelimab, Xencor conducted a Phase 2 trial of obexelimab in patients with SLE, where the primary endpoint was not achieved with statistical significance. The results of our clinical trials of obexelimab in SLE or other indications or our clinical trials for any other product candidates may not achieve statistical significance or demonstrate a favorable risk-benefit profile. Further, negative clinical trial results for a product candidate with respect to one indication may impact the potential or perceived potential of other indications. Moreover, clinical data are often susceptible to varying interpretations and analyses, and many companies that have believed their product candidates performed satisfactorily in clinical trials have nonetheless failed to obtain marketing approval of such product candidates. Commencing any future clinical trials is subject to finalizing the trial design and submitting an application, such as an IND or BLA, to the FDA or a comparable foreign regulatory authority. Even after the submission of an IND or BLA, the FDA or comparable foreign regulatory authorities could disagree that their requirements to commence a clinical trial have been satisfied or disagree with the study design, which may require the completion of additional trials or the amendment of the 63 Table of Contents trial’s protocols or the imposition of stricter conditions on the commencement of the clinical trial. We may be unable to establish clinical endpoints, dose levels and regimens or bioanalytical assay methods that regulatory authorities would consider clinically meaningful. A high failure rate characterizes product candidates proceeding through clinical trials, and failure may occur at all stages of the clinical trial process. Most product candidates that commence clinical trials are never approved as products, and our current or future clinical trials ultimately may fail to support the approval of our current or any future product candidates. We expect to continue to rely, in part, on collaborators, CROs and clinical trial sites to conduct our clinical trials, including participant enrollment, and we have limited influence over their performance. We or our collaborators may experience delays in initiating or completing clinical trials and preclinical studies or other issues that delay or prevent our ability to receive marketing approval or commercialize our current and any future product candidates, including: ● the FDA or comparable foreign regulatory authorities may require us to conduct additional preclinical studies or impose additional requirements before permitting us to initiate a clinical trial; ● the FDA or comparable foreign regulatory authorities, Institutional Review Boards (“IRBs”) or ethics committees may disagree with our study design, may require that we modify or amend our clinical trial protocols, or may not authorize us or our investigators to commence or conduct a clinical trial at a prospective trial site; ● we may experience delays in reaching, or fail to reach, agreement on acceptable terms with trial sites and CROs, the terms of which can be subject to extensive negotiation and may vary significantly; ● clinical investigators or clinical trial sites may deviate from trial protocols or Good Clinical Practice requirements (“GCPs”) or drop out of a trial, and we may need to add new investigators or sites; ● our CROs may fail to comply with regulatory requirements or meet their contractual obligations to us in a timely manner, if at all; ● the number of participants required for clinical trials may be larger than expected, enrollment in clinical trials may be slower than expected or participants may drop out or fail to return for post-treatment follow-up at a higher rate than expected; ● we may observe unexpectedly high placebo response rates; ● the cost of clinical trials and preclinical studies may be greater than we anticipate, or we may have insufficient funds to conduct such trial or study or to pay the substantial user fees required by the FDA upon the submission of a BLA; ● the supply or quality of our product candidates or other materials necessary to conduct our clinical trials or preclinical studies may be insufficient or inadequate to initiate or complete a given clinical trial; ● our product candidates may have undesirable side effects or other unexpected characteristics that are viewed to outweigh their potential benefits; ● reports from clinical testing of other similar therapies may raise safety, tolerability or efficacy concerns about our product candidates; and ● clinical trials of our product candidates may fail to show appropriate safety, tolerability or efficacy, may produce negative or inconclusive results or may otherwise fail to improve on the existing standard of care, and we may decide, or regulators may require us, to conduct additional clinical trials or preclinical studies or we may decide to abandon product candidate development. 64 Table of Contents In addition, delays occur when a clinical trial is suspended, put on clinical hold or terminated by the trial sponsor, the FDA or comparable foreign regulatory authorities, or the IRBs of the institutions in which such trials are being conducted, or when a clinical trial is recommended for suspension or termination by a data safety monitoring board. Suspensions and terminations are imposed due to a number of factors, including failure to conduct a clinical trial in accordance with regulatory requirements or trial protocols, failure to conduct the trial in accordance with GCPs or applicable regulatory guidelines, failed inspections of clinical trial operations or trial sites by the FDA or comparable foreign regulatory authorities, unforeseen safety issues or adverse side effects, failure to establish or achieve clinically meaningful trial endpoints, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. Clinical trials frequently are delayed or terminated as a result of ambiguous or negative interim results or unanticipated adverse events. If trials or tests are not positive or are only modestly positive or if there are safety concerns, we may be required to repeat or conduct additional clinical trials or preclinical studies for our product candidates beyond those that we currently contemplate, we may be delayed in or prevented from obtaining marketing approval or may obtain marketing approval in some countries and not in others, we may obtain approval for indications or patient populations that are not as broad as intended or desired or obtain approval with significant use or distribution restrictions or safety warnings, be subject to post-marketing testing requirements, or be subject to increased pricing pressure. Many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials also ultimately may lead to the denial of regulatory approval of a product candidate. Further, the FDA or comparable foreign regulatory authorities may disagree with our clinical trial design and our interpretation of data from clinical trials or may change the requirements for approval even after they have reviewed and commented on the design for our clinical trials. When we conduct preclinical and clinical research in collaboration with other academic, pharmaceutical and biotechnology entities, we risk additional delays due to the frequent need to align on decisions. Our product development costs have increased, and may continue to increase, when we experience delays in clinical testing. Our clinical trials may not begin when expected, may require restructuring or may not be completed on schedule, or at all. Significant clinical trial delays also shorten any periods during which we may have the exclusive right to commercialize our product candidates and may allow our competitors to bring products to market before we do, potentially impairing our ability to successfully manufacture and commercialize our product candidates, if approved. Delays and increased costs in our clinical development programs would harm our business, financial condition, results of operations and prospects. Delays or difficulties in the enrollment and dosing of patients in clinical trials, delay or prevent receipt of necessary regulatory approvals. The timing of our clinical trials depends on our ability to recruit patients to participate in our studies as well as the dosing of such patients and completion of required follow-up periods. Participant enrollment, a significant factor in the timing of clinical trials, is affected by many factors, including the size and nature of the patient population, the number and location of clinical sites, the proximity of participants to clinical sites, the eligibility and exclusion criteria for the trial, the design of the clinical trial, challenges in obtaining and maintaining participant consents, enrolled participants dropping out, competing clinical trials and clinicians’ and patients’ perceptions as to the potential advantages of the product candidate being studied in relation to other available therapies, including any new drugs or biologics that may be approved for the indications being investigated by us. Rare or orphan diseases like IgG4-RD pose additional risk due to the difficulty identifying study subjects and ensuring each participant’s disease state meets the study parameters. Further, because screening for many of these diseases is not widely adopted, and because it can be difficult to diagnose these diseases in the absence of screening, it can be difficult to find patients who are eligible to participate in our studies or trials. In addition, our clinical trials currently, and may in the future, compete with other clinical trials for product candidates that address the same disease as our product candidates, and this competition reduces the number and types of participants available to us, because some participants who might have opted to enroll in our trials instead opt to enroll in a trial conducted by a competitor or elect to use a marketed therapy. We also could encounter delays if doctors face ethical challenges associated with enrolling participants in a clinical trial rather than prescribing an existing treatment with an established safety and efficacy profile. 65 Table of Contents If we or our collaborators are unable to enroll a sufficient number of eligible patients to participate in our clinical trials, we may not be able to initiate, continue or complete clinical trials for our product candidates. Even if we are able to enroll a sufficient number of participants in our clinical trials, delays in enrollment may result in increased costs, delay completion or adversely impact the outcome of the trial. Additionally, our ability to successfully initiate, enroll, and complete a clinical trial in any foreign country is subject to numerous risks unique to conducting business in foreign countries, including: difficulty in establishing or managing relationships with CROs and physicians; different standards for the conduct of clinical trials; different standard-of-care for patients with a particular disease; difficulty in locating qualified local consultants, physicians and partners; and potential burden of complying with a variety of foreign laws, medical standards and regulatory requirements, including the regulation of pharmaceutical and biotechnology products and treatment. We have experienced participant withdrawals or discontinuations from our trials. Participants, including in any control groups, frequently withdraw from a clinical trial if they are not experiencing improvement in their underlying disease or condition or if they experience adverse side effects or other issues. Withdrawal of participants from our clinical trials may compromise the quality of our data. Difficulties enrolling a sufficient number of patients to conduct our clinical trials as planned could require us to delay, limit or terminate clinical trials for our product candidates, or expand to additional jurisdictions, which could impose additional challenges on our company. Failure to successfully conduct our clinical trials as planned, would have an adverse effect on our business, financial condition, results of operations and prospects. Any significant adverse events or undesirable side effects caused by our product candidates may delay or prevent regulatory approval or market acceptance of our product candidates, or result in significant negative consequences following marketing approval, if any. Unacceptable, undesirable or clinically unmanageable side effects, caused by any of our product candidates could cause us or regulatory authorities to interrupt, delay or halt our clinical trials and could result in a more restrictive label or the delay or denial of marketing approval by the FDA or comparable foreign regulatory authorities. We have observed certain adverse events (“AEs”) and SAEs in our clinical trials of obexelimab administered through IV infusion. Our clinical trials of obexelimab are administered through SC injection. In the Phase 1 pharmacokinetic (“PK”) and relative bioavailability study of obexelimab administered either intravenously or subcutaneously, the most common related treatment emergent adverse events (“TEAEs”) across all SC dose regimens were headache and injection site reactions. GI-related events seen with IV infusions were not observed in subjects who received SC formulation, but future studies may reveal similar issues. AEs, SAEs or other side effects in clinical trials often make it difficult to recruit participants to clinical trials and results in participants dropping out of trials. While certain side effects may be reversible following discontinuation of the product candidate with sufficient recovery periods, we will need to monitor the severity and duration of side effects in our clinical trials. If such effects are more severe, less reversible than we expect or not reversible at all, we may decide, or be required, to perform additional studies or to halt or delay further clinical development of our product candidates. While we believe that obexelimab has the potential to offer benefits, including in regard to its side-effect profile, over B cell depleting agents, if obexelimab is shown to have adverse events, side effects or other safety or tolerability concerns, then our opportunity to disrupt the current standard of care will be limited. AEs and SAEs may be deemed to be related to our product candidates. Such a determination may require longer and more extensive clinical development, or regulatory authorities may increase the amount of data and information required to approve, market or maintain approval of our product candidates. We, the FDA or other applicable regulatory authorities, or an IRB, may suspend clinical trials of a product candidate at any time for various reasons, including a belief that participants in such trials are being exposed to unacceptable health risks or adverse side effects. Many potential product candidates developed in the biotechnology industry that initially showed promise in early-stage trials have later been found to cause side effects that prevented their further development and 66 Table of Contents approval. Even if side effects do not preclude the product candidate from obtaining or maintaining marketing approval, undesirable side effects may inhibit market acceptance. Even if we successfully develop a product candidate and it receives marketing approval, the FDA could require us to adopt a Risk Evaluation and Mitigation Strategy (“REMS”) to ensure that the benefits of treatment outweigh the risks for each potential patient, which may include, among other things, a medication guide outlining the risks of the product for distribution to patients, a communication plan to healthcare practitioners, extensive patient monitoring or distribution systems and processes that are highly controlled, restrictive, and more costly than what is typical for the industry. Furthermore, if we or others later identify undesirable side effects caused by any product candidate that we obtain marketing approval for, several potentially significant negative consequences could result, including: ● regulatory authorities may limit, suspend or withdraw approvals of such product, or may refuse to approve supplemental applications for such product; ● regulatory authorities may require additional warnings on the label, such as a “Boxed Warning,” contraindications or precautions, or otherwise limit the approved use of such product; ● regulatory authorities may impose additional restrictions on the marketing of, or the manufacturing processes for, the particular product, including requiring a REMS; ● we may be required to recall the product or change the way it is administered in patients; ● we may be required to conduct additional clinical trials; ● we may decide to remove such product from the market; ● we could be sued and held liable for harm caused to patients; and ● our reputation may suffer. Any of these events could prevent us from obtaining or maintaining regulatory approvals or achieving or maintaining market acceptance of our current and future product candidates or could substantially increase the costs and expenses of commercializing the affected product, which in turn could significantly impact our ability to successfully commercialize our product candidates and generate revenues. Risks associated with the in-licensing or acquisition of product candidates could cause substantial delays in the preclinical and clinical development of our product candidates. We have relied on, and continue to rely on, our licensing partners, such as Xencor, to have (i) conducted research and development in accordance with the applicable protocol, legal, regulatory and scientific standards, (ii) accurately reported the results of all clinical trials conducted prior to our acquisition of the relevant product candidates and (iii) correctly collected and interpreted the data from these trials. If the research and development processes or the results of the development programs prior to our acquisition of our product candidates prove to be unreliable, this could result in increased costs and delays in the development of our product candidates, which could adversely affect any future revenue from such product candidates, if approved. We may also acquire or in-license additional product candidates for preclinical or clinical development in the future as we continue to build our pipeline. The risks associated with acquiring or in-licensing product candidates could result in delays in the commencement or completion of our preclinical studies and clinical trials, if ever, and our ability to generate revenues from our product candidates may be delayed. Please see “—Risks Related to Our Intellectual Property—We may not obtain or maintain necessary rights to our product candidates through acquisitions and in-licenses” for additional information regarding such risks. 67 Table of Contents We face potential competition from different sources that have made substantial investments into the rapid development of novel treatments for immunological indications, including large and specialty pharmaceutical and biotechnology companies, many of which already have approved therapies in our current indications. The biotechnology and pharmaceutical industries are characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary drugs. While we believe that our knowledge, experience and scientific resources provide us with competitive advantages, we face potential competition from many different sources, including large and specialty pharmaceutical and biotechnology companies, academic research institutions and governmental agencies, as well as public and private research institutions. Any product candidates that we successfully develop and commercialize, if approved, will compete with existing therapies and new therapies that may become available in the future. The key competitive factors affecting the success of all of our product candidates, if approved, are likely to be their safety, efficacy, convenience, price, the level of generic competition, the existence of therapeutic alternatives and the availability of coverage and reimbursement from government and other third-party payors. Many of the companies against which we are competing, or against which we may compete in the future, have significantly greater financial resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approvals and marketing approved drugs than we do. Mergers and acquisitions in the pharmaceutical and biotechnology industries may result in even more resources being concentrated among a smaller number of our competitors. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to, or necessary for, our programs. Our current product candidates, initially under development for treatment of various I&I indications would, if approved, face competition from existing approved immunological treatments, many of which have achieved commercial success. For example, we are currently developing obexelimab for the treatment of IgG4-RD, MS, and SLE. There are currently no approved therapies for IgG4-RD, but there are two products approved for SLE, and a number of products approved for MS. Moreover, there are a number of product candidates in clinical development by other companies for IgG4-RD, MS, and SLE that may become available in the future, including UPLIZNA (inebilizumab-cdon), an anti-CD19 antibody being developed by Amgen Inc., for which Amgen filed a BLA based on the results of its Phase 3 trial in patients with IgG4-RD. To compete successfully, we need to disrupt currently marketed drugs, meaning we must demonstrate that the relative cost, method of administration, safety, tolerability and efficacy of our product candidates provides a better alternative to existing and new therapies. Our commercial opportunity and likelihood of success will be reduced or eliminated if our product candidates are not ultimately demonstrated to be safer, more effective, more conveniently administered or less expensive than the current standard of care or future competing products. Furthermore, even if our product candidates are able to achieve these attributes, acceptance of our products may be inhibited by the reluctance of physicians to switch from existing therapies to our products, or if physicians choose to reserve our products for use in limited circumstances. Competitive products may make any products we develop obsolete or noncompetitive before we recover the expense of development and commercialization. Such competitors could also recruit our employees, which could negatively impact our level of expertise and our ability to execute our business plan. If we are not able to effectively compete for any of the foregoing reasons, our business will be materially harmed. Interim , initial, “top-line” and preliminary data from our clinical trials that we announce or publish from time to time are subject to audit and verification procedures and may differ materially from final data as more patient data become available. Preliminary or top-line data from our preclinical studies and clinical trials that we publish from time to time are based on preliminary analyses of then-available data, and the results, related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular preclinical study or clinical trial. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate all data. As a result, the top-line or preliminary results may differ from 68 Table of Contents future results of the same studies or trials, or different conclusions or considerations may qualify such results once additional data have been received and fully evaluated. Top-line data also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data. As a result, top-line data should be viewed with caution until the final data are available. From time to time, we also may disclose interim data from our preclinical studies and clinical trials. Interim data from clinical trials are subject to the risk that one or more of the clinical outcomes may materially change as participant enrollment continues and more participant data become available or as participants from our clinical trials continue other treatments for their disease. Furthermore, third parties, including regulatory authorities, may not accept or agree with our assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could delay or prevent regulatory approval of, or limit commercial prospects for, the particular product candidate. In addition, the information we choose to publicly disclose regarding a particular study or clinical trial is based on what is typically extensive information, and investors or others may not agree with what we determine to disclose. If the interim, top-line or preliminary data that we report differ from final results, or if others, including regulatory authorities, disagree with the conclusions reached, our ability to obtain approval for, and commercialize, our product candidates may be harmed, which could harm our business, financial condition, results of operations and prospects. Further, disclosure of interim, top-line or preliminary data by us or by our competitors could result in volatility in the price of our common stock . Our ongoing Phase 3 trial of obexelimab for IgG4-RD and other clinical trials of obexelimab, even if successfully completed, may not be sufficient for approval of obexelimab for the applicable indication. FDA approval of a new biologic generally requires data from two well-controlled Phase 3 trials of the relevant biologic in the relevant patient population; however, in some cases the FDA may accept data from a single Phase 3 trial to support marketing approval. We are conducting a Phase 3 trial of obexelimab for IgG4-RD, and we believe the results of this trial may be sufficient to support submission of a BLA for this indication. Although we have discussed our plans with the FDA, we do not have any agreement from the FDA that our regulatory development plans will provide adequate safety and efficacy data for the proposed dosing regimen or otherwise be sufficient for submission of a BLA. The FDA may require that we conduct additional clinical trials, including a comparative trial against an approved therapy, which would significantly delay our development timelines and require substantially more resources. If we are required to conduct two Phase 3 clinical trials for IgG4-RD, then our development timeline would be extended, and the related expenses would be significantly increased. Although obexelimab has been granted orphan drug designation by the FDA for IgG4-RD, such designation does not guarantee that any regulatory authority will accept fewer trials, accelerate regulatory review of, or ultimately approve obexelimab for IgG4-RD. If the FDA does not agree with our planned strategy, the FDA may ultimately require us to conduct additional Phase 3 clinical trials prior to approval of an indication. In addition, the standard of care may change with the approval of new products in the same indications that we are studying. This may result in the FDA or other regulatory authorities requesting additional studies to show that our product candidate is superior to the new products. ​ 69 Table of Contents We may not realize the benefits of our current or future collaborations or licensing arrangements and may be unsuccessful in consummating future partnerships. Our current or future collaborations or licensing arrangements may not be successful. Additionally, we have partnered, and intend to further partner, with third parties with respect to the clinical development and commercialization, if approved, of certain of our programs in certain regions outside the U.S. and Europe, and we may not be successful in identifying, negotiating and executing partnerships. The success of our collaboration arrangements will depend heavily on the efforts and activities of our collaborators. Collaborations are subject to numerous risks, which may include that: ● collaborators have significant discretion in determining the efforts and resources that they will apply to collaborations; ● collaborators may not pursue development and commercialization of our product candidates or may elect not to continue or renew development or commercialization programs based on trial or test results, changes in their strategic focus due to the acquisition of competitive products, availability of funding or other external factors, such as a business combination that diverts resources or creates competing priorities; ● agreements with collaborators may not provide exclusive rights to use their intellectual property and technology in all relevant fields of use and in all territories in which we may wish to develop or commercialize our technology and product candidates in the future; ● collaborators could independently develop, or develop with third parties, products that compete directly or indirectly with our product candidates; ● a collaborator with marketing, manufacturing and distribution rights to one or more products may not commit sufficient resources to or otherwise not perform satisfactorily in carrying out these activities; ● the grant of exclusive rights to our collaborators would prevent us from collaborating with others; ● collaborators may not properly maintain or defend our intellectual property rights or may use our intellectual property or proprietary information in a way that gives rise to actual or threatened litigation that could jeopardize or invalidate our intellectual property or proprietary information or expose us to potential liability; ● disputes may arise between us and a collaborator that cause the delay or termination of the research, development or commercialization of our future product candidates or that result in costly litigation or arbitration that diverts management attention and resources; ● collaborations may be terminated, and, if terminated, may result in a need for additional capital to pursue further development or commercialization of the applicable future product candidates; ● collaborators may own or co-own intellectual property covering our product candidates that results from our collaborating with them, and in such cases, we would not have the exclusive right to develop or commercialize such intellectual property; and ● a collaborator’s sales and marketing activities or other operations may not be in compliance with applicable laws resulting in civil or criminal proceedings. Even if we complete the necessary clinical trials, we cannot predict when, or if, we will obtain regulatory approval to commercialize any product candidate in the U.S. or any other jurisdiction, and any such approval may be for a more narrow indication than we seek. We cannot commercialize a product candidate unless and until the appropriate regulatory authorities have reviewed and approved the product candidate. Even if our product candidates meet their safety and efficacy endpoints in clinical trials, the regulatory authorities may not complete their review processes in a timely manner, or we may not be able to obtain 70 Table of Contents regulatory approval. Additional delays may result if an FDA Advisory Committee or other regulatory authority recommends non-approval or restrictions on approval. In addition, we may experience delays or rejections based upon additional government regulation from future legislation or administrative action, or changes in regulatory authority policy during the period of product development, clinical trials, and the review process. Regulatory authorities may approve a product candidate for more limited indications than requested or they may impose significant limitations in the form of narrow indications, warnings or a REMS. These regulatory authorities may require labeling that includes precautions or contraindications with respect to conditions of use, or they may grant approval subject to the performance of costly post marketing clinical trials. In addition, regulatory authorities may not approve the labeling claims that we believe are necessary or desirable for the successful commercialization of any product candidates we may develop. Any of the foregoing scenarios could materially harm the commercial prospects for our product candidates and adversely affect our business, financial condition, results of operations, and prospects. Our clinical trial results may not support approval and our product candidates could fail to receive regulatory approval for many reasons, including the following: ● the FDA or comparable foreign regulatory authorities may disagree with the design or implementation of our clinical trials; ● we may be unable to demonstrate to the satisfaction of the FDA or comparable foreign regulatory authorities that our product candidates are safe and effective for any of their proposed indications; ● the results of clinical trials may not meet the level of statistical significance required by the FDA or comparable foreign regulatory authorities for approval, including due to the heterogeneity of patient populations, or apparent improvement in trial participants receiving placebo; ● we may be unable to demonstrate that our product candidates’ clinical and other benefits outweigh their safety risks; ● the FDA or comparable foreign regulatory authorities may disagree with our interpretation of data from preclinical studies or clinical trials; ● the data collected from clinical trials of our product candidates may not be sufficient to the satisfaction of the FDA or comparable foreign regulatory authorities to support the submission of a BLA or other comparable submission in foreign jurisdictions or to obtain regulatory approval in the U.S. or elsewhere; ● the FDA or comparable foreign regulatory authorities may not approve our CMOs’ manufacturing process or facilities; ● the FDA may not accept clinical data from trials conducted by individual investigators or in countries where the standard of care is potentially different from the U.S.; and ● the approval policies or regulations of the FDA or comparable foreign regulatory authorities may significantly change in a manner rendering our clinical data insufficient for approval. Regulatory approval for our product candidates may not be obtained without lengthy delays, if at all. Any delay in obtaining, or inability to obtain, applicable regulatory approvals would prevent us from commercializing our product candidates. We may expend our limited resources to pursue a particular product candidate in specific indications and fail to capitalize on product candidates or indications that may be more profitable or for which there is a greater likelihood of success. Because we have limited financial and managerial resources, we focus our development efforts on certain selected product candidates in certain selected indications. For example, we are initially focused on our lead product candidate, obexelimab, 71 Table of Contents for the treatment of IgG4-RD, MS, and SLE. As a result, we may forgo or delay pursuit of opportunities with other product candidates or other indications for our existing product candidates that later prove to have greater commercial potential. Additionally, negative clinical trial results with respect to one indication of a product candidate may impact the potential or perception of other indications of the product candidate. Our resource allocation decisions may result in our failure to capitalize on viable commercial products or profitable market opportunities. Our spending on current and future development programs and product candidates for specific indications may not yield any commercially viable product candidates. If we do not accurately evaluate the commercial potential or target market for a particular product candidate, we may relinquish valuable rights to that product candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to such product candidate. We are currently conducting, and may in the future conduct, clinical trials for current or future product candidates outside the U.S., and the FDA and comparable foreign regulatory authorities may not accept data from such trials. We are currently conducting clinical trials outside the U.S., including in Europe and Asia, and we expect to continue to conduct trials internationally in the future. The acceptance of data from clinical trials conducted outside the U.S. by the FDA or comparable foreign regulatory authorities may be subject to certain conditions or may not be accepted at all. In cases where data from foreign clinical trials are intended to serve as the basis for marketing approval in the U.S., the FDA will generally not approve the application unless the data are applicable to the U.S. population and U.S. medical practice, the trials were performed by clinical investigators of recognized competence and pursuant to GCP regulations and the FDA is able to validate the data through an on-site inspection or other appropriate means. Additionally, the FDA’s clinical trial requirements, including sufficient size of patient populations and statistical powering, must be met. Many comparable foreign regulatory authorities have similar approval requirements. In addition, foreign trials are subject to local laws of the foreign jurisdictions where the trials are conducted. The FDA or any comparable foreign regulatory authority may not accept data from trials conducted outside of the U.S. or the applicable jurisdiction, which would result in the need for additional trials that could be costly and time consuming and could result in the product candidate not receiving approval for commercialization in the applicable jurisdiction. Even if we receive marketing approval for our current or future product candidates in the U.S., we may never receive regulatory approval to market outside of the U.S. We plan to seek regulatory approval of our current or future product candidates outside of the U.S. In order to market any product outside of the U.S. we must establish and comply with the numerous and varying safety, efficacy and other regulatory requirements of other applicable jurisdictions. Marketing approval processes vary among countries but generally implicate all of the risks detailed above regarding FDA approval in the U.S. as well as other risks. The time required to obtain approvals in other countries might differ substantially from that required to obtain FDA approval and can require additional product candidate testing and additional administrative review periods. In many countries outside of the U.S., products must receive pricing and reimbursement approval before the product can be commercialized. Obtaining this approval can result in substantial delays in bringing products to market in such countries. Marketing approval in one country does not ensure marketing approval in another, but a failure or delay in obtaining marketing approval in one country may have a negative effect on the regulatory process in others and would impair our ability to market our current or future product candidates in such foreign markets. Any such impairment would limit the commercial potential of the product candidate, which could adversely affect our business, financial condition, results of operations and prospects. The successful commercialization of our product candidates, if approved, will depend in part on the extent to which governmental authorities and other third party payors establish broad coverage, adequate reimbursement levels and favorable pricing for our products. Failure to obtain or maintain such coverage , reimbursement and pricing for any approved products could limit our ability to market those products and would decrease our ability to generate revenue. The availability of coverage and the adequacy of reimbursement by governmental healthcare authorities or programs such as Medicare and Medicaid, private health insurers and other third-party payors are essential for most patients to be able to afford prescription medications such as our product candidates, if approved. Our ability to achieve coverage and acceptable levels of reimbursement for our approved products by third-party payors will affect our ability to successfully commercialize those products. No uniform policy for coverage and reimbursement for products exists among third-party payors in the U.S. Coverage and reimbursement for products can therefore differ significantly from payor to payor. Even 72 Table of Contents if we obtain coverage for a given product by a third-party payor, the reimbursement payment rates may not be adequate or may require co-payments that patients find unacceptably high. Coverage and adequate reimbursement in the U.S. or elsewhere may not be available for any product that we may develop, and any coverage or reimbursement that may be obtained could be reduced or eliminated in the future. There is significant uncertainty related to third-party payor coverage and reimbursement of newly approved products. The coverage determination process is often time consuming and costly and may require us to provide scientific and clinical support for the use of our products to each payor separately, with no assurance that coverage will be obtained. Third party payors may not provide or may limit coverage, including to a subset of the patient population for which the treatment is approved by the FDA, or may control utilization including by requiring that patients try other therapies first or that prescribers obtain specific approval of coverage on a patient by patient basis. Many third-party payors refuse to provide coverage and reimbursement for particular drugs when equivalent generic drugs, biosimilars or less expensive therapies are available. A third-party payor may consider our product candidates, if approved, as substitutes for alternative products on the market now or in the future and only be willing to cover the cost of the alternative product. Third-party payors increasingly are challenging prices charged for biopharmaceutical products and services. Even if we show improved efficacy, safety or convenience of administration with obexelimab or any of our other product candidates, pricing of competitive products may limit the amount we will be able to charge for any of our product candidates, if approved. Third-party payors may deny or revoke the reimbursement status of a product or establish payment for new or existing marketed products at levels that are too low to enable us to realize an appropriate return on our investment in our product candidates. When new competitor generic and biosimilar products enter the market, pricing or reimbursement for the innovator compound may be reduced. More generally, the existence of generic and biosimilar products or other therapeutic alternatives within a “therapeutic category” may result in reduced reimbursement from payors. Additionally, new competitor brand drugs can trigger therapeutic category reviews in the interest of modifying coverage and/or reimbursement levels. We may be required to provide discounts or rebates under government healthcare programs or to certain government and private purchasers in order to obtain coverage under federal healthcare programs such as Medicaid. More generally, we may need to offer price concessions to third party payors to obtain favorable coverage or to purchasers to achieve sales. Such actions could have a negative impact on our ability to successfully commercialize any of our product candidates, if approved. Additionally, if a companion diagnostic test is developed for use with a drug product, any coverage and reimbursement for that test would be separate and apart from the coverage and reimbursement sought for such drug product. A lack of coverage or adequate reimbursement for such a test could adversely affect access to a drug product. Outside the U.S., international operations are generally subject to extensive governmental price controls and other market regulations, and we believe the increasing emphasis on cost-containment initiatives in Europe and other countries has and will continue to put pressure on the pricing and usage of products like our product candidates. In many countries, the prices of medical products are subject to varying price control mechanisms as part of national health systems. Other countries allow companies to fix their own prices for medical products but monitor and control company profits. Additional foreign price controls or other changes in pricing regulation could restrict the amount that we are able to charge for our product candidates, if approved. Accordingly, in markets outside the U.S., the reimbursement for our product candidates may be lower than in the U.S. and may be insufficient to generate meaningful revenue and profits. Factors outside the U.S. that may be relevant in pricing and reimbursement determinations by health authorities, including in European countries, may include, without limitation, perceived cost-effectiveness perceived benefit to patient quality of life, and designation as an orphan drug indication, among others. Moreover, increasing efforts by governmental and third-party payors in the U.S. and abroad to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for our products, if approved. We expect to experience pricing pressures for any of our product candidates that may be approved due to the continuing trend toward managed healthcare and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs and surgical procedures and other treatments, has become very intense. As a result, increasingly high barriers are being erected to the entry of new products. 73 Table of Contents We may not be able to obtain or maintain orphan drug designations for certain of our product candidates, and we may be unable to maintain the benefits associated with orphan drug designation, including the potential for market exclusivity. Regulatory authorities in some jurisdictions, including the U.S. and Europe, may designate drugs for relatively small patient populations as orphan drugs. For example, the FDA may designate a product as an orphan product if it is intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals in the U.S., or a patient population of greater than 200,000 individuals in the U.S. but for which there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the U.S. The FDA and the EMA have each granted orphan drug designation to obexelimab for IgG4-RD. We may not be able to maintain orphan drug designation for obexelimab for IgG4-RD. Additionally, we may not be able to obtain orphan drug designation for any additional indications for our product candidates, and we may not be able to maintain such designations if granted. Generally, if a product with an orphan drug designation subsequently receives the first marketing approval for the indication for which it has such designation, the product is entitled to a period of marketing exclusivity, which precludes the FDA from approving another marketing application for the same biologic for the same indications for seven years. Even if we are able to maintain orphan drug designation for IgG4-RD or obtain orphan drug exclusivity for any other indication or product candidate, that exclusivity may not effectively protect the product from competition because different drugs can be approved for the same condition. Even after an orphan drug is approved, the FDA can subsequently approve the same drug for the same condition if, among other things, the FDA concludes that the later drug is clinically superior, if it is shown to be safer, more effective or makes a major contribution to patient care. The EMA is required to re-assess granted orphan designation at the time of marketing authorization to ensure that it continues to meet the criteria for the designation to be maintained. Otherwise, the orphan designation can be revoked. Orphan drug designation does not convey any advantage in or shorten the duration of the regulatory review and approval process. Even if we receive orphan drug designation or orphan drug exclusivity for any of our product candidates, there is no guarantee that we will enjoy the benefits of such designations or exclusivity periods, and granted designations, if not maintained, will not provide the benefits of such designation. The decision of the U.S. Court of Appeals for the 11th Circuit in Catalyst Pharms., Inc. v. Becerra , 14 F.4 th 1299 (11 th Cir. 2021) has created uncertainty regarding the scope of orphan drug exclusivity. Although the FDA subsequently announced that it intends to continue to apply its longstanding interpretation of the regulations to matters outside of the scope of the Catalyst order and continue tying the scope of orphan-drug exclusivity to the uses or indications for which a drug is approved, it is unclear how future litigation, legislation, agency decisions, and administrative actions will impact the scope of the orphan drug exclusivity. We may seek fast track designation, breakthrough therapy designation and/or priority review designation from the FDA or similar designations from comparable foreign regulatory authorities for one or more of our product candidates. Even if one or more of our product candidates receive these designations, we may be unable to obtain or maintain the benefits associated with such designation. The FDA has established various designations to facilitate more rapid and efficient development and approval of certain types of drugs intended to treat serious conditions that fill an unmet medical need. Such designations include fast track designation, breakthrough therapy designation, and priority review designation. We intend to seek priority review designation for obexelimab for IgG4-RD. The FDA has broad discretion whether or not to grant this designation, so even if we believe a particular product candidate is eligible for this designation, the FDA could decide not to grant it. If any of our programs or product candidates receive any of these designations by the FDA or similar designations by comparable foreign regulatory authorities, there is no assurance that we will receive any benefits from such programs or that we will continue to meet the criteria to maintain such designation. Even if we obtain such designations, we may not experience a faster development process, review or approval compared to conventional procedures. A grant of these designations does not ensure that a product candidate will receive marketing approval or that approval will be granted within any particular timeframe. In addition, the FDA may withdraw any such designation if it believes that the designation is no longer supported by data from our clinical development program. 74 Table of Contents We may seek accelerated approval for some of our product candidates but may not be able to obtain it as the sufficiency of our clinical trial results for accelerated approval are subject to the FDA’s discretion. We may explore strategies for our product candidates that involve use of the FDA’s accelerated approval pathway. Obtaining accelerated approval requires demonstration of meaningful benefit over available therapies for a serious condition. The determination of what constitutes available therapy is wholly up to the FDA and is subject to change. No assurance can be given that other therapeutics will not receive full approval prior to our potential receipt of accelerated approval. If that were to occur, no assurance can be given that we would be successful in proving meaningful benefit over those later approved products. If we were unable to prove meaningful benefit over any such agents, we would be effectively blocked from receiving accelerated approval. If any of our drugs were ever to receive accelerated approval, we would be required to conduct a post-market confirmatory study, which we may not complete, or if completed, may prove unsuccessful. In such instance, the FDA can remove the product from the market. Risks Related to Our Business and Operations Our business depends entirely on the success of our product candidates, and we may fail to successfully develop, receive regulatory approval for, or successfully commercialize any or all of our product candidates. We do not have any products approved for commercial sale. We have invested substantially all of our efforts and financial resources in the development of our product candidates, each of which is still in clinical development, and we expect that we will continue to invest heavily in these product candidates and any future product candidates we may develop. Our business and our ability to generate revenue, which we do not expect will occur for many years, if ever, are substantially dependent on our ability to acquire, develop, obtain regulatory approval for and successfully commercialize our product candidates, which may never occur. Our product candidates will require substantial additional clinical development time, regulatory approval, commercial manufacturing arrangements, establishment of a commercial organization, significant marketing efforts and further investment before we can generate any revenue from product sales. We may not meet our timelines for our current or future clinical trials, which may be delayed or not completed for a number of reasons (see “—Risks Related to Product Candidate Development and Commercialization—Clinical development is lengthy and expensive, characterized by uncertain outcomes, with results of earlier studies and trials often failing to predict future trial results. We may incur additional costs or experience delays in completing, or fail to complete, the development and commercialization of our current product candidates or any future product candidates.”). Our product candidates are susceptible to the risks of failure inherent at any stage of product development, including the appearance of unexpected AEs or failure to achieve primary endpoints in clinical trials. Even if our product candidates are successful in clinical trials, we are not permitted to market or promote any product candidate before we receive regulatory approval from the FDA or comparable foreign regulatory authorities. If we do not receive FDA or comparable foreign regulatory approval with the necessary conditions to allow commercialization, we will not be able to generate revenue from those product candidates in the U.S. or elsewhere in the foreseeable future, or at all. We have never submitted a BLA for our product candidates to the FDA, or a similar marketing application to a comparable foreign regulatory authority, and our current or any future product candidates may not be successful in clinical trials or receive regulatory approval. If approved for marketing by applicable regulatory authorities, our ability to generate revenue from our product candidates will depend on our ability to: ● receive regulatory approval for the targeted patient populations and claims that are necessary or desirable for successful marketing and maintain an acceptable safety profile for the products following approval; ● price our products competitively such that third-party and government reimbursement permits broad product adoption; ● obtain and maintain healthcare coverage and adequate reimbursement; 75 Table of Contents ● achieve market acceptance of our products by patients, the medical community and third-party payors; ● demonstrate the superiority of our products compared to the standard of care, as well as other therapies in development; ● create market demand for our product candidates through our own marketing and sales activities or any co-promotion or other arrangements that we may otherwise establish; ● manufacture product candidates through CMOs in sufficient quantities and at acceptable quality and cost to meet commercial demand at launch and thereafter; ● establish sales and marketing capabilities, whether alone or through a collaboration, to support commercialization of our product candidates; ● establish and maintain agreements with wholesalers, distributors, pharmacies and group purchasing organizations on commercially reasonable terms; ● obtain, maintain, protect and enforce patent and other intellectual property protection and regulatory exclusivity for our products; ● maintain compliance with applicable laws, regulations and guidance including interactions with healthcare professionals, patient advocacy groups and communication of healthcare economic information to payors and formularies; ● maintain a distribution and logistics network capable of product storage within our specifications and regulatory guidelines, and capable of timely product delivery; and ● assure that our product will be used as directed and that additional unexpected safety risks will not arise. Any significant delays in obtaining approval for or inability to successfully commercialize our product candidates would adversely affect our business, financial condition, results of operations and prospects. We are dependent on the services of our senior management and other clinical and scientific personnel, and if we are not able to retain these individuals or recruit additional management or clinical and scientific personnel, our business will suffer. Our success depends in part on our continued ability to attract, retain and motivate highly qualified management, clinical and scientific personnel. We are highly dependent upon our Founder and Chief Executive Officer, Leon O. Moulder, Jr. We are also dependent on our President and Chief Operating Officer, Joseph Farmer, Chief Business Officer and Chief Financial Officer, Jennifer Fox, and Chief Commercial Officer, Orlando Oliveira and other members of our senior management and clinical development teams. The loss of services of any of these individuals could delay or prevent the successful development of our product pipeline, initiation or completion of our preclinical studies and clinical trials or the commercialization of our product candidates, if approved. Although we have executed employment agreements or offer letters with each member of our senior management team, these agreements are terminable at will with or without notice and, therefore, we may not be able to retain their services. We do not currently maintain “key person” life insurance on the lives of our executives or any of our employees. This lack of insurance means that we may not have adequate compensation for the loss of the services of these individuals. We will need to expand and effectively manage our managerial, operational, financial and other resources in order to successfully pursue our clinical development and commercialization efforts. We may not be successful in maintaining our unique company culture and continuing to attract or retain qualified management and scientific and clinical personnel in the future due to the intense competition for qualified personnel among biopharmaceutical, biotechnology and other businesses, particularly in the greater Boston area. If we are not able to attract, integrate, retain and motivate personnel 76 Table of Contents necessary to accomplish our business objectives, we may experience constraints that significantly impede the achievement of our development objectives, our ability to raise additional capital and our ability to implement our business strategy. We will need to grow our organization, and we may experience difficulties in managing our growth and expanding our operations, which could adversely affect our business. As our development and commercialization plans and strategies develop, and as we transition into operating as a public company, we expect to expand our employee base for managerial, operational, financial and other resources. As our product candidates enter and advance through preclinical studies and clinical trials, we will need to expand our development and regulatory capabilities and contract with third parties to provide manufacturing and other capabilities for us. In the future, we expect to have to manage additional relationships with collaborators or partners, suppliers and other organizations. Our ability to manage our operations and future growth will require us to continue to improve our operational, financial and management controls, reporting systems and procedures, and we may not be able to implement improvements in an efficient or timely manner or may discover deficiencies in existing systems and controls. Our inability to successfully manage our growth and expand our operations could adversely affect our business, financial condition, results of operations and prospects. The manufacturing of our product candidates is complex, and our third-party manufacturers may encounter difficulties in production. If our third-party manufacturers encounter such difficulties, our ability to provide supply of our product candidates for clinical trials, our ability to obtain marketing approval, or provide commercial supply of our products, if approved, could be delayed or halted. Our product candidates are biopharmaceuticals and the process of manufacturing biopharmaceuticals is complex, time consuming, highly regulated and subject to multiple risks. Our CMOs must comply with legal requirements, current Good Manufacturing Practices requirements (“cGMPs”) and guidelines for the manufacturing of biopharmaceuticals used in clinical trials and, if approved, marketed products. Our CMOs may have limited experience in the manufacturing of cGMP batches of our products. Manufacturing biopharmaceuticals is highly susceptible to drug product loss due to contamination, equipment failure, improper installation or operation of equipment, vendor or operator error, inconsistency in yields, variability in product characteristics and difficulties in scaling the production process. The impact of drug product loss is compounded by the long lead times needed to procure additional drug product due to plant capacity limitations or other restrictions at our CMOs. Even minor deviations from normal manufacturing processes could result in reduced production yields, lot failures, product defects, product liability claims, or other supply disruptions. If microbial, viral or other contaminations are discovered at our third-party manufacturers’ facilities, such facilities may need to be closed for an extended period of time to investigate and remedy the contamination, which could delay clinical trials and adversely affect our business. Problems in third-party manufacturing process or facilities could restrict our ability to ensure sufficient clinical material for our clinical trials or delay or prevent us from obtaining marketing approval. Scaling up a biopharmaceutical manufacturing process is a difficult and uncertain task and involves additional risks, including cost overruns, process scale-up, process reproducibility, stability issues, compliance with cGMPs, lot consistency and timely availability of sufficient quantity of raw materials. Even if we obtain regulatory approval for any of our product candidates, manufacturers may not be able to manufacture the approved product to specifications acceptable to the FDA or other comparable foreign regulatory authorities, to produce it in sufficient quantities to meet the requirements for the potential launch of the product or to meet potential future demand. If our third-party manufacturers are unable, or decide not, to adequately validate or scale-up the manufacturing process at our current manufacturers’ facilities, we will need to transfer to another manufacturer and complete the manufacturing validation process, which can be lengthy. If our manufacturers are unable to produce sufficient quantities of drug substance and/or drug product for clinical trials or for commercialization we will need to identify and negotiate with other CMOs an agreement for clinical and/or commercial supply and it is not certain we will be able to come to agreement timely or on terms acceptable to us, which would likely jeopardize our ability to provide any product candidates to study subjects in clinical trials and products to patients, if approved. Any delay or interruption in clinical trial supplies will likely delay the completion of planned clinical trials, increases the costs associated with maintaining clinical trial programs and, depending upon the period of delay, could require new 77 Table of Contents clinical trials at additional expense or terminate clinical trials completely. Any adverse developments affecting clinical or commercial manufacturing of our product candidates or products may result in shipment delays, inventory shortages, lot failures, product withdrawals or recalls, or other interruptions in the supply of our product candidates or products. We may also have to take inventory write-offs and incur other charges and expenses for product candidates or products that fail to meet specifications, undertake costly remediation efforts or seek more costly manufacturing alternatives. Accordingly, failures or difficulties faced at any level of our supply chain could adversely affect our business and delay or impede the development and commercialization of any of our product candidates or products, if approved, and could have an adverse effect on our business, financial condition, results of operations and prospects. As part of our process development efforts, we also may make changes to the manufacturing processes at various points during development, for various reasons, such as controlling costs, achieving scale, decreasing processing time, increasing manufacturing success rate, proximity to global regions we intend to target or other reasons. Such changes may not achieve their intended objectives, and any of these changes could cause our current or future product candidates to perform differently or affect the results of our future clinical trials. In some circumstances, changes in the manufacturing process require us to perform ex vivo comparability studies and to collect additional data from participants prior to undertaking more advanced clinical trials. For instance, changes in our process during the course of clinical development may require us to show the comparability of the product used in earlier clinical phases or at earlier portions of a clinical trial to the product used in later clinical phases or later portions of the clinical trial. This could delay completion of clinical trials, require the conduct of bridging clinical trials or the repetition of one or more clinical trials, increase clinical trial costs, delay approval of our product candidates and jeopardize our ability to commence sales and generate revenue. Revenue from our product candidates, if approved, will be limited if the product does not achieve broad market acceptance. As a company, we have never commercialized a product candidate for any indication. Even if a product candidate is approved by the appropriate regulatory authorities for marketing and sale, it may not gain acceptance among physicians, patients, third-party payors and others in the medical community. If any product candidate for which we obtain regulatory approval does not gain an adequate level of market acceptance, we may not generate sufficient product revenue or become profitable. The degree of market acceptance of any of our product candidates will depend on a number of factors, some of which are beyond our control, including: ● the safety, efficacy, tolerability and ease of administration of our product candidates; ● the prevalence and severity of side effects and AEs associated with our product candidates, and how the safety and tolerability profile of our product candidates compares to those of existing or emerging therapies; ● the clinical indications for which the products are approved and the approved claims that we may make for the products; ● limitations or warnings contained in the product’s FDA-approved labeling, including potential limitations or warnings that may be more restrictive than competitive products; ● distribution and use restrictions imposed by the FDA with respect to such product candidates or to which we agree as part of a mandatory REMS or voluntary risk management plan; ● changes in the standard of care for the targeted indications for such product candidates; ● cost of treatment as compared to the clinical benefit in relation to alternative treatments or therapies; ● the availability of adequate coverage and reimbursement by third parties, such as insurance companies and other healthcare payors, and by government healthcare programs, including Medicare and Medicaid; 78 Table of Contents ● the extent and strength of our marketing and distribution of such product candidates; ● the safety, efficacy and other potential advantages of, and availability of, alternative treatments already used or that may later be approved for any of our intended indications; ● the timing of market introduction of such product candidates, as well as competitive products; ● the reluctance of physicians to switch their patients’ current standard of care; ● the reluctance of patients to switch from their existing therapy regardless of the safety and efficacy of newer products; ● our ability to offer such product candidates for sale at competitive prices; ● the extent and strength of our third-party manufacturer and supplier support; ● adverse publicity about our product or favorable publicity about competitive products; and ● potential product liability claims. Our efforts to educate the medical community and third-party payors as to the benefits of our product candidates may require significant resources and may never be successful. Even if the medical community accepts that our product candidates are safe and effective for their approved indications, physicians and patients may not be receptive to such product candidates and may be slow to adopt them as an accepted treatment. If our current or future product candidates are approved, but do not achieve an adequate level of acceptance among physicians, patients and third-party payors, we may not generate meaningful revenue from our product candidates and may never become profitable. Misconduct or other improper actions, including noncompliance with regulatory standards and requirements, by our employees, independent contractors, consultants, commercial partners and vendors exposes us to potential noncompliance with regulatory standards and requirements. Employee fraud or other illegal activity by our employees, independent contractors, consultants, commercial partners, CROs, CMOs and vendors exposes us to liability. Misconduct by these parties could be intentional, reckless and/or negligent conduct, including failure to comply with FDA or other regulations, provide true, complete and accurate information to the FDA or comparable foreign regulatory authorities, comply with manufacturing standards we may establish, comply with healthcare fraud and abuse laws and regulations, report financial information or data accurately or disclose unauthorized activities to us. If we obtain FDA approval of any of our product candidates and begin commercializing those products in the U.S., our potential exposure under these laws will increase significantly, as will our costs associated with compliance. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. Misconduct could also involve the improper use of information obtained in the course of clinical trials or creation of fraudulent data in preclinical studies or clinical trials, which could result in regulatory sanctions and serious harm to our reputation. Additionally, a person could allege fraud or other misconduct even if none occurred. It is not always possible to identify and deter employee misconduct, and the precautions we take to detect and prevent this activity may not be effective in controlling known or unknown risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to comply with such laws or regulations. Any such actions instituted against us could have a material and adverse effect on our business, financial condition, results of operations and prospects, including the imposition of significant civil, criminal or administrative penalties, damages, fines, disgorgement, imprisonment, the curtailment or restructuring of our operations, loss of eligibility to obtain approvals from the FDA, exclusion from participation in government contracting, healthcare reimbursement or other government programs, including Medicare and Medicaid, integrity oversight and reporting obligations, or reputational harm. 79 Table of Contents Our estimates of commercial opportunities for product candidates and forecasts of market growth may prove to be smaller than we believe, and even if the markets in which we compete achieve the forecasted growth, our business may not grow at similar rates, or at all. We intend to initially focus our product candidate development on treatments for various I&I indications. Our projections of addressable patient populations within any particular disease state that may benefit from treatment with our product candidates are based on our estimates. Market opportunity estimates and growth forecasts are subject to significant uncertainty and are based on assumptions and estimates. Our estimates, which have been derived from a variety of sources, including scientific literature, surveys of clinics, patient foundations and market research, may prove to be incorrect in general or as to their applicability to our company. Further, new studies or trials may change the estimated incidence or prevalence of these diseases. For example, IgG4-RD is a relatively recently described disease that incorporates groups of manifestations that were diagnosed as separate disease entities prior to 2003. We estimate that the currently diagnosed population of IgG4-RD patients in the U.S. is approximately 20,000, with what we believe to be comparable prevalence rates globally. Additionally, the potentially addressable patient population for our product candidates may not ultimately be amenable to treatment with our product candidates. Our commercial opportunity may also be limited by future competitor treatments that enter the market with such patients. If any of our estimates prove to be inaccurate, the commercial opportunity for any product candidate that we or our strategic partners develop could be significantly diminished and have an adverse material impact on our business. Even if we obtain significant market share for our product candidates, because some of our potential target populations are very small, we may never achieve profitability despite obtaining such significant market share. Our future growth may depend, in part, on our ability to operate in foreign markets, where we would be subject to additional regulatory burdens and other risks and uncertainties. Our future growth may depend, in part, on our ability to develop and commercialize our product candidates in foreign markets, including in the European Union (“EU”), United Kingdom (“UK”), Japan and China for which we may rely on collaboration with third parties. We are not permitted to market or promote any of our product candidates before we receive regulatory approval from the applicable regulatory authority in that foreign market, and we may not obtain foreign regulatory approvals on a timely basis, if at all. To obtain separate regulatory approval in other countries, we must comply with numerous and varying regulatory requirements of such countries regarding safety and efficacy and governing, among other things, clinical trials and commercial sales, pricing and distribution of our product candidates. If we fail to comply with the regulatory requirements in international markets or fail to receive applicable marketing approvals, our ability to realize the full commercial potential of our product candidates will be harmed. Failure to obtain approval of any of our product candidates by regulatory authorities in another country may significantly diminish the commercial prospects of that product candidate and our business, financial condition, results of operations and prospects could be adversely affected. Moreover, even if we obtain approval of our product candidates and ultimately commercialize our product candidates in foreign markets, we would be subject to the risks and uncertainties, including the burden of complying with complex and changing foreign regulatory, tax, accounting and legal requirements and reduced protection of intellectual property rights in some foreign countries. Strategic transactions could impact our liquidity, increase our expenses and present significant distractions to our management. As a core part of our strategy, we intend to enter into strategic transactions, which could include acquisitions of companies, asset purchases and in-licensing and out-licensing of intellectual property. For example, we in-licensed the exclusive global rights to develop and commercialize obexelimab, ZB002 and ZB004 from Xencor, and, in August 2023, we entered into a strategic license and collaboration with BMS, pursuant to which we granted the exclusive rights to develop and, if approved, commercialize obexelimab in Japan, South Korea, Taiwan, Hong Kong, Singapore and Australia. The expected synergies in development programs, pipelines and other areas of focus between Zenas, Xencor and BMS may not be realized on a timely basis or at all, and there may be risks associated with the acquisition that we did not previously anticipate, such as unanticipated liabilities. 80 Table of Contents We also may enter into a variety of other business arrangements, including strategic collaborations, joint ventures, restructurings, divestitures, business combinations and investments. Any future transactions could increase our near and long-term expenditures, result in potentially dilutive issuances of our equity securities, including our common stock, or the incurrence of debt, contingent liabilities, amortization expenses or acquired in-process research and development expenses, any of which could affect our business, financial condition, liquidity and results of operations. Future acquisitions may require us to obtain additional financing, which may not be available on favorable terms or at all. These transactions may never be successful and may require significant time and attention of our management. In addition, the integration of any business or assets may be disruptive, complex, risky and costly and we may never realize the full benefits of the acquisition. Recent and future changes to tax laws could adversely affect our company. The tax regimes we are subject to or operate under, including with respect to income and non-income taxes, are unsettled and may be subject to significant change. Changes in tax laws, regulations, or rulings, or changes in interpretations of existing laws and regulations, could adversely affect our company. For example, the Tax Cuts and Jobs Act, the Coronavirus Aid, Relief, and Economic Security Act, and the Inflation Reduction Act of 2022 (the “IRA”) enacted many significant changes to the U.S. tax laws. Future guidance from the Internal Revenue Service and other tax authorities with respect to such legislation may affect us, and certain aspects thereof could be repealed or modified in future legislation. For example, the IRA includes provisions that will impact the U.S. federal income taxation of certain corporations, including imposing a 15% minimum tax on the book income of certain large corporations and a 1% excise tax on certain corporate stock repurchases that would be imposed on the corporation repurchasing such stock. If our internal information technology systems, or those used by our CROs, CMOs, clinical sites or other contractors or consultants, are or were compromised, become unavailable or suffer security incidents, loss or leakage of data or other disruptions, we could suffer material adverse consequences, including operational or service interruption, harm to our reputation, litigation, fines, penalties, compromise of sensitive information related our business and other adverse consequences. In the ordinary course of our business, we, and the third parties upon which we rely, process sensitive data and as a result, we and the third parties upon which we rely face a variety of evolving threats which could cause security incidents. Our internal information technology systems and those of our CROs, CMOs, clinical sites and other contractors and consultants are vulnerable to cyberattacks, computer viruses, bugs, worms, or other malicious codes, malware (including as a result of advanced persistent threat intrusions) and other attacks by computer hackers, cracking, application security attacks, social engineering (including through phishing attacks), supply chain attacks and vulnerabilities through our third-party service providers, denial-of-service attacks (such as credential stuffing), credential harvesting, personnel misconduct or error, supply-chain attacks, software bugs, server malfunctions, software or hardware failures, loss of data or other information technology assets, adware, telecommunications failures, earthquakes, fires, floods and other similar threats. Such threats are prevalent and continue to rise, are increasingly difficult to detect and come from a variety of sources, including traditional computer “hackers,” threat actors, “hacktivists,” organized criminal threat actors, personnel (such as through theft or misuse), sophisticated nation states and nation-state-supported actors. In particular, ransomware attacks, including those from organized criminal threat actors, nation-states and nation-state supported actors, are becoming increasingly prevalent and severe and can lead to significant interruptions, delays, or outages in our operations, loss of data (including sensitive customer information), loss of income, significant extra expenses to restore data or systems, reputational loss and the diversion of funds. To alleviate the negative impact of a ransomware attack, it may be preferable to make extortion payments, but we may be unwilling or unable to do so (including, for example, if applicable laws or regulations prohibit such payments, or our insurance carrier objects to payment). Some actors, including nation-state actors, also engage in cyber-attacks for geopolitical reasons and in conjunction with military conflicts and defense activities. During times of war and other major conflicts, we and the third parties upon which we rely are vulnerable to a heightened risk of these attacks, including retaliatory cyber-attacks, that could materially disrupt our systems and operations, supply chain and ability to conduct our development activities, including clinical trials. In addition to experiencing a security incident, third parties may gather, collect or infer sensitive information 81 Table of Contents about us from public sources, data brokers or other means that reveals competitively sensitive details about our organization and could be used against us. Additionally, remote work increases risks to our information technology systems and data, as more of our employees utilize network connections, computers and devices outside our premises or network, including working at home, while in transit and in public locations. We may be vulnerable to attacks as a result of vulnerabilities introduced through our supply chain, including vendors we engage to provide us with security and other technologies. Furthermore, future or past business transactions (such as acquisitions or integrations) could expose us to additional cybersecurity risks and vulnerabilities present in acquired or integrated entities’ systems and technologies, including security issues that are not identified during due diligence. Additionally, it may be difficult to integrate companies into our information technology environment and security program. We may not be able to detect and remediate all vulnerabilities and the threats and techniques used to exploit such vulnerabilities change frequently and are often sophisticated in nature. Therefore, vulnerabilities could be exploited but may not be detected until after a security incident has occurred. Further, we may experience delays in developing and deploying remedial measures designed to address any such identified vulnerabilities. We rely on third-party service providers and technologies to operate critical business systems to process sensitive information in a variety of contexts, including cloud-based infrastructure, encryption and authentication technology, employee email and other functions. We also rely on third-party service providers to assist with our clinical trials, provide other products or services or otherwise to operate our business. Our ability to perform diligence on or monitor third parties’ information security practices is limited, and third parties may not have adequate information security measures in place. If our third-party service providers experience a security incident or other interruption, we could experience adverse consequences. While we may be entitled to damages if our third-party service providers fail to satisfy their privacy or security-related obligations to us, any award may be insufficient to cover our damages, or we may be unable to recover such award. If the information technology systems of our CROs, CMOs, clinical sites and other contractors and consultants become subject to disruptions or security incidents, we may have insufficient recourse against such third parties and we may have to expend significant resources to mitigate the impact of such an event, and to develop and implement protections to prevent future events of this nature from occurring. In addition, supply-chain attacks have increased in frequency and severity, and we cannot guarantee that third parties and infrastructure in our supply chain or our third-party partners’ supply chains have not been compromised or that they do not contain exploitable defects or bugs that could result in a breach of or disruption to our information technology systems (including our services) or the third-party information technology systems that support us. A security incident or other interruption could result in unauthorized, unlawful or accidental acquisition, modification, destruction, loss, alteration, encryption, disclosure of, or access to our sensitive data or our information technology systems, or those of the third parties upon whom we rely, any of which could disrupt our ability (and that of third parties upon whom we rely) to advance clinical development or commercial activities for any products, if approved. For example, the loss of clinical trial data from completed or ongoing clinical trials could result in delays in our regulatory approval efforts, significantly increase our costs to recover or reproduce the data or limit our ability to effectively execute a product recall, if required. In addition, we could incur liability if any disruption or security incident results in the loss of or damage to our data or applications, or inappropriate disclosure of personal, confidential or proprietary information. Applicable data privacy and security obligations also may require us to notify relevant stakeholders of security incidents. Such disclosures are costly, and the disclosure or the failure to comply with such requirements could lead to adverse consequences. Any disruption or security incident could result in legal claims or proceedings, liability under laws that protect the privacy of personal information and significant regulatory penalties, damage to our reputation or a loss of confidence in us and our ability to conduct clinical trials, which could delay the clinical development of our product candidates. Although we have obtained cyber insurance, we cannot be sure that our insurance coverage will be adequate or sufficient to protect us from or to mitigate liabilities arising out of a cybersecurity incident or that such coverage will continue to be available on commercially reasonable terms in the future. 82 Table of Contents Our business entails a significant risk of product liability and our ability to obtain sufficient insurance coverage could adversely affect our business, financial condition, results of operations and prospects. As we conduct clinical trials of our current or future product candidates, we are exposed to significant product liability risks inherent in the development, testing, manufacturing and marketing of new therapies. Product liability claims could delay or prevent completion of our development programs. If we succeed in obtaining approval to market any product candidate, product liability claims could result in FDA or other investigation of the safety and effectiveness of our future product candidates, our manufacturing processes and facilities or our marketing programs and potentially a recall of our products or more serious enforcement action, limitations on the approved indications for which they may be used or suspension or withdrawal of approvals. Regardless of the merits or eventual outcome, liability claims may also result in decreased demand for our product candidates, termination of clinical trial sites or entire trial programs, withdrawal of clinical trial participants or inability to enroll participants, injury to our reputation and significant negative media attention, significant costs to defend the related litigation, a diversion of management’s time and our resources from our business operations, substantial monetary awards to trial participants or patients, loss of revenue, the inability to commercialize and products that we may develop, and a decline in our stock price. We may require higher levels of product liability insurance for later stages of clinical development or marketing any of our product candidates, and our insurance may not provide sufficient coverage against potential liabilities. Furthermore, clinical trial and product liability insurance is becoming increasingly expensive. As a result, we may be unable to obtain sufficient insurance at a reasonable cost to protect us against losses caused by product liability claims that could adversely affect our business, financial condition, results of operations and prospects. Public opinion and scrutiny of I&I treatments may impact public perception of our company and product candidates, or may adversely affect our ability to conduct our business and our business plans. Public perception may be influenced by claims, such as claims that our product candidates are unsafe, unethical or immoral and, consequently, our approach may not gain the acceptance of the public or the medical community. Negative public reaction to I&I treatments in general could result in greater government regulation and stricter labeling requirements of products to treat immunological diseases, including any of our product candidates, if approved, and could cause a decrease in the demand for any product candidates we may develop. Moreover, our success will depend upon physicians specializing in the treatment of those diseases that our product candidates target prescribing, and their patients being willing to receive, treatments that involve the use of our product candidates in lieu of, or in addition to, existing treatments they are already familiar with and for which greater clinical data may be available. AEs in our clinical trials, even if not ultimately attributable to our product candidates, and the resulting publicity could result in withdrawal of clinical trial participants or impact our ability to enroll participants or lead to increased governmental regulation, unfavorable public perception, potential regulatory delays in the testing or approval of our product candidates, stricter labeling requirements for those product candidates that are approved and a decrease in demand for any such product candidates. More restrictive government regulations or negative public opinion could have an adverse effect on our business, financial condition, results of operations and prospects, and may delay or impair the development and, if approved, commercialization of our product candidates or demand for any products we may develop. Risks Related to Our Intellectual Property If we are unable to obtain and maintain sufficient intellectual property protection for our product candidates or any future product candidates we may develop, or if the scope of the intellectual property protection obtained is not sufficiently broad, our competitors or other third parties could develop and commercialize products similar or identical to ours, and our ability to successfully develop and commercialize our product candidates may be adversely impacted. We rely upon a combination of patents, know-how and confidentiality agreements to protect the intellectual property related to our product candidates and to prevent third parties from copying and surpassing our achievements, thus eroding our competitive position in our market. Our success depends in large part on our ability to obtain and maintain patent protection in the U.S. and other countries for our product candidates and their uses, as well as our ability to operate without infringing, misappropriating or otherwise violating the proprietary rights of others. We seek to protect our proprietary position by filing and licensing patent applications in the U.S. and abroad related to our novel discoveries and technologies that are important to our business. 83 Table of Contents Although we in-license issued patents, we do not own any issued patents and our pending and future patent applications may not result in patents being issued. Issued patents may not afford sufficient protection of our product candidates or their intended uses against competitors, and the patents issued may be infringed, designed around, invalidated by third parties, or may not effectively prevent others from commercializing competitive technologies, products or product candidates. Obtaining and enforcing patents is expensive and time consuming, and we may not be able to file, prosecute, maintain, enforce or license all necessary or desirable patent applications or maintain and/or enforce patents that may issue based on our patent applications, at a reasonable cost or in a timely manner. We may not be able to obtain or maintain patent applications and patents due to the subject matter claimed in such patent applications and patents being in disclosures in the public domain. It is also possible that we will fail to identify patentable aspects of our research and development results before it is too late to obtain patent protection. Although we enter into non-disclosure and confidentiality agreements with parties who have access to confidential or patentable aspects of our research and development output, such as our employees, corporate collaborators, outside scientific collaborators, CROs, CMOs, consultants, advisors and other third parties, any of these parties may breach these agreements and disclose such results before a patent application is filed, thereby jeopardizing our ability to seek patent protection. Consequently, we may not be able to prevent third parties from using our technology that is in the public domain. Composition of matter patents for biological and pharmaceutical product candidates often provide a strong form of intellectual property protection for those types of products, as such patents provide protection without regard to any method of use. However, the claims in our or our collaborators’ or licensors’ pending patent applications directed to composition of matter of our product candidates may not be considered patentable by the USPTO or by patent offices in foreign countries, or the claims in any of our or our licensors’ issued patents may not be considered valid and enforceable by courts in the U.S. or foreign countries. Method of use patents protect the use of a product for the specified method. This type of patent does not prevent a competitor from making and marketing a product that is identical to our product candidates for an indication that is outside the scope of the patented method. Moreover, even if competitors do not actively promote their product for our targeted indications, clinicians may prescribe these products “off-label.” Although off-label prescriptions may infringe or contribute to the infringement of method of use patents, the practice is common and such infringement is difficult to prevent or prosecute. The patent position of biopharmaceutical companies generally is highly uncertain, involves complex legal and factual questions and has in recent years been the subject of much litigation, resulting in court decisions, including Supreme Court decisions, which have increased uncertainties as to the ability to enforce patent rights in the future. As a result, the issuance, scope, validity, enforceability and commercial value of any patent rights are highly uncertain. Our pending and future owned and in-licensed patent applications may not result in patents being issued which protect our product candidates, effectively prevent others from commercializing our product candidates or otherwise provide any competitive advantage. In fact, patent applications may not issue as patents at all. The coverage claimed in a patent application can also be significantly reduced before the patent is issued, and its scope can be reinterpreted after issuance. In addition, the laws of foreign countries may not protect our rights to the same extent as the laws of the U.S., or vice versa. The patent application process is subject to numerous risks and uncertainties, and we may not be successful in protecting our product candidates by obtaining and defending patents. For example, we may not be aware of all third-party intellectual property rights potentially relating to our product candidates or their intended uses, and as a result the impact of such third-party intellectual property rights upon the patentability of our own or our licensors’ patents and patent applications, as well as the impact of such third-party intellectual property upon our freedom to operate, is highly uncertain. Publications of discoveries in the scientific literature often lag behind the actual discoveries, and patent applications in the U.S. and other jurisdictions are typically not published until 18 months after filing or, in some cases, not at all. Therefore, we cannot know with certainty whether we were the first to make the inventions claimed in our patents or pending patent applications, or that we were the first to file for patent protection of such inventions. If a third party can establish that we or our licensors were not the first to make or the first to file for patent protection of such inventions, our owned or licensed patent applications may not issue as patents and even if issued, may be challenged and invalidated or rendered unenforceable. As a result, the issuance, inventorship, scope, validity, enforceability and commercial value of our or our licensors’ patent rights are highly uncertain. 84 Table of Contents The issuance of a patent is not conclusive as to its inventorship, scope, validity or enforceability and our or our licensors’ pending patent applications may be challenged in patent offices in the U.S. and abroad. Even issued patents may later be found invalid or unenforceable or may be modified or revoked in proceedings instituted by third parties before various patent offices or in courts. For example, our or our licensors’ pending patent applications may be subject to third-party pre-issuance submissions of prior art to the USPTO or our issued patents may be subject to post-grant review proceedings, oppositions, derivations, reexaminations, interferences, inter partes review proceedings or other similar proceedings, in the U.S. or elsewhere, challenging our or our licensors’ patent rights or the patent rights of others. Such submissions may also be made prior to a patent’s issuance, precluding the granting of a patent based on one or more of our owned or licensed pending patent applications. An adverse determination in any such challenges may result in loss of exclusivity or in patent claims being narrowed, invalidated, or held unenforceable, in whole or in part, which could limit our ability to stop others from using or commercializing similar or identical technology and product candidates, or limit the duration of the patent protection of our technology and product candidates. Such challenges also may result in substantial cost and require significant time from our scientists and management, even if the eventual outcome is favorable to us. Any of the foregoing could adversely affect our business, financial condition, results of operations and prospects. A third party may also claim that our owned or licensed patent rights are invalid or unenforceable in a litigation. The outcome following legal assertions of invalidity and unenforceability is unpredictable. An adverse result in any legal proceeding could put one or more of our owned or in-licensed patents at risk of being invalidated or interpreted narrowly and could allow third parties to commercialize our products and compete directly with us, without payment to us, or result in our inability to manufacture or commercialize our technology, products or product candidates without infringing third-party patent rights. In addition, given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. The degree of future protection for our proprietary rights is uncertain. Only limited protection may be available and may not adequately protect our rights or permit us to gain or keep any competitive advantage. Any failure to obtain or maintain patent protection with respect to our product candidates or their uses could adversely affect our business, financial condition, results of operations and prospects. We have in-licensed patent portfolios, but have no solely owned issued patents relating to our product candidates. Although we exclusively in-license patent portfolios from Xencor related to obexelimab, ZB002 and ZB004, we have no solely owned issued patents. Although the exclusively in-licensed patent portfolios contain pending patent applications, we may not obtain any issued patents from the pending applications directed to our product candidates. Claims in our U.S. pending patent applications, corresponding international patent applications and patent applications in certain foreign jurisdictions, or those of our licensors, may not be considered patentable by the USPTO, courts in the U.S. or by the patent offices and courts in foreign countries, and any issued claims may be found invalid or unenforceable if challenged. Additionally, our provisional applications may never result in issued patents. Accordingly, we or our licensors may never obtain issued patents or that any issued patents we or our licensors obtain may not provide us with any competitive advantage. Failure to obtain adequate patent protection for our product candidates and technology could adversely affect our business, financial condition, results of operations and prospects. We may not obtain or maintain necessary rights to our product candidates through acquisitions and in- licenses. The growth of our business depends in part on our ability to acquire, in-license, or use third-party proprietary rights, and we may not be able to do so on commercially reasonable terms or at all. Licenses may be on nonexclusive terms, thereby giving our competitors and other third parties access to the same intellectual property licensed to us, or could require us to make substantial licensing and royalty payments. The licensing and acquisition of third-party intellectual property rights is a competitive area, and a number of more established companies may pursue strategies to license or acquire third-party intellectual property rights that we may consider attractive or necessary. These established companies may have a competitive advantage over us due to their size, capital resources or greater clinical development and commercialization capabilities. In addition, companies that perceive us to be a competitor may be unwilling to assign or license rights to us. We also may be unable to license or acquire third-party intellectual property rights on terms that would allow us to make an appropriate return on our investment or at all. If we are unable to successfully obtain rights to required third-party intellectual property rights or maintain the existing intellectual property rights we have obtained, we may have to abandon 85 Table of Contents development of the relevant program or product candidate, which could adversely affect our business, financial condition, results of operations, and prospects. While we normally seek to obtain the right to control prosecution, maintenance and enforcement of the patents relating to our product candidates, there may be times when the filing and prosecution activities for patents and patent applications relating to our product candidates are controlled by our licensors or collaboration partners. For example, under our license and collaboration agreements with Xencor, Xencor is responsible for patent prosecution of certain licensed intellectual property. If any of our current or future licensors or collaboration partners fails to prosecute, maintain and enforce such patents and patent applications in a manner consistent with the best interests of our business, including by payment of all applicable fees for patents covering our product candidates, we could lose our rights to the intellectual property or our exclusivity with respect to those rights, our ability to develop and commercialize those product candidates may be adversely affected and we may not be able to prevent competitors from making, using and selling competing products. In addition, even where we have the right to control patent prosecution of patents and patent applications we have licensed to and from third parties, we may still be adversely affected or prejudiced by actions or inactions of our licensees, our future licensors and their counsel that took place prior to the date upon which we assumed control over patent prosecution. Patent rights relating to inventions described and claimed in our or our licensors’ pending patent applications may not issue and patents based on our or our licensors’ patent applications could be challenged and rendered invalid and/or unenforceable. The patent application process is subject to numerous risks and uncertainties, and we, our licensors, or any of our potential future collaborators may not be successful in protecting our product candidates by obtaining and defending patents. We and our licensors have several pending U.S. and foreign patent applications in our portfolio. We cannot predict: ● if and when patents may issue based on our and our licensors’ patent applications; ● the scope of protection of any patent issuing based on our and our licensors’ patent applications; ● whether the claims of any patent issuing based on our and our licensors’ patent applications will provide protection against competitors; ● whether or not third parties will find ways to invalidate or circumvent our and our licensors’ patent rights; ● whether or not others will obtain patents claiming aspects similar to those covered by our and our licensors’ patents and patent applications; ● whether we will need to initiate litigation or administrative proceedings to enforce and/or defend our and our licensors’ patent rights which will be costly whether we win or lose; ● whether the patent applications that we own will result in issued patents with claims that cover our product candidates or uses thereof in the U.S. or in other foreign countries; or ● whether we may experience patent office interruption or delays to our ability to timely secure patent coverage to our product candidates due to global pandemics and epidemics. The claims in our or our licensors’ pending patent applications directed to our product candidates may not be considered patentable by the USPTO or by patent offices in foreign countries, and any such patent applications may not issue as granted patents. One aspect of the determination of patentability of our and our licensors’ inventions depends on the scope and content of the “prior art,” information that was or is deemed available to a person of skill in the relevant art prior to the priority date of the claimed invention. There may be prior art of which we are not aware that may affect the patentability of our or our licensors’ patent claims or, if issued, affect the validity or enforceability of a patent claim. Even if the patents do issue based on our or our licensors’ patent applications, third parties may challenge the validity, enforceability or scope thereof, which may result in such patents being narrowed, invalidated or held unenforceable. For example, there may be prior art not considered by the patent office that is raised by a third party to challenge the validity of any patents that issue 86 Table of Contents from our or our licensors' patent applications. Furthermore, even if they are unchallenged, patents in our and our licensors’ portfolio may not adequately exclude third parties from practicing relevant technology or prevent others from designing around our claims. If the breadth or strength of our intellectual property position with respect to our product candidates is threatened, it could dissuade companies from collaborating with us to develop and threaten our ability to commercialize our product candidates. In the event of litigation or administrative proceedings, we cannot be certain that the claims in any of our issued patents will be considered valid by courts in the U.S. or foreign countries. We may not be able to protect our intellectual property rights throughout the world. Patents are of national or regional effect. Filing, prosecuting and defending patents on all of our research programs and product candidates in all countries throughout the world would be prohibitively expensive, and our and our licensors’ intellectual property rights in some countries outside the U.S. can be less extensive than those in the U.S. In addition, the laws of some foreign countries do not protect intellectual property rights to the same extent as federal and state laws in the U.S., even in jurisdictions where we do pursue patent protection. Consequently, we may not be able to prevent third parties from practicing our or our licensors’ inventions in all countries outside the U.S., even in jurisdictions where we or our licensors do pursue patent protection, or from selling or importing products made using our or our licensors’ inventions in and into the U.S. or other jurisdictions. Competitors may use our or our licensors’ technologies in jurisdictions where we have not obtained patent protection to develop their own products and, further, may export otherwise infringing products to territories where we and our licensors have patent protection, but enforcement is not as strong as that in the U.S. These competitor products may compete with our product candidates, and our and our licensors’ patents or other intellectual property rights may not be effective or sufficient to prevent them from competing. Various companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of many countries do not favor the enforcement of patents and other intellectual property protection, particularly those relating to pharmaceuticals, which could make it difficult for us to stop the infringement of our and our licensors’ patents or marketing of competing products in violation of our proprietary rights. Various countries outside the U.S. have compulsory licensing laws under which a patent owner may be compelled to grant licenses to third parties. In addition, many countries limit the enforceability of patents against government agencies or government contractors. As a result, a patent owner may have limited remedies in certain circumstances, which could materially diminish the value of such patent. If we or our licensors are forced to grant a license to third parties with respect to any patents relevant to our business, our competitive position may be impaired, and our business, financial condition, results of operations and prospects may be adversely affected. Accordingly, our efforts to enforce our intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we develop or license. Further, the standards applied by the USPTO and foreign patent offices in granting patents are not always applied uniformly or predictably. As such, we do not know the degree of future protection that we will have on our product candidates. While we will endeavor to try to protect our product candidates with intellectual property rights such as patents, as appropriate, the process of obtaining patents is time consuming, expensive and unpredictable. Intellectual property rights do not necessarily address all potential threats to our competitive advantage. The degree of future protection afforded by our intellectual property rights is uncertain because intellectual property rights have limitations and may not adequately protect our business or permit us to maintain our competitive advantage. For example: ● others may be able to make product candidates that are similar to ours but that are not covered by the pending patent applications that we own or the patents or patent applications that we license; ● we or our licensors or future collaborators might not have been the first to make the inventions covered by the pending patent application that we own or have exclusively licensed; ● we or our licensors or future collaborators might not have been the first to file patent applications covering certain of our or their inventions; 87 Table of Contents ● others may independently develop similar or alternative technologies or duplicate any of our technologies without infringing or otherwise violating our owned or licensed intellectual property rights; ● it is possible that noncompliance with the USPTO and foreign governmental patent agencies requirement for a number of procedural, documentary, fee payment and other provisions during the patent process can result in abandonment or lapse of a patent or patent application, and partial or complete loss of patent rights in the relevant jurisdiction; ● it is possible that our pending owned or licensed patent applications or those that we may own or license in the future will not lead to issued patents; ● issued patents that we either own or have exclusively licensed may be revoked, modified, or held invalid or unenforceable, as a result of legal challenges by our competitors; ● others may have access to the same intellectual property rights licensed to us in the future on a non-exclusive basis; ● our competitors might conduct research and development activities in countries where we do not have patent rights and then use the information learned from such activities to develop competitive products for sale in our major commercial markets; ● we may not develop additional proprietary technologies that are patentable; ● we cannot predict the scope of protection of any patent issuing based on our and our licensors’ patent applications, including whether the patent applications that we own, presently in-license, or, in the future, in-license will result in issued patents with claims that directed to our product candidates or uses thereof in the U.S. or in other foreign countries; ● there may be significant pressure on the U.S. government and international governmental bodies to limit the scope of patent protection both inside and outside the U.S. for disease treatments that prove successful, as a matter of public policy regarding worldwide health concerns; ● countries other than the U.S. may have patent laws less favorable to patentees than those upheld by U.S. courts, allowing foreign competitors a better opportunity to create, develop and market competing product candidates; ● the claims of any patent issuing based on our patent applications may not provide protection against competitors or any competitive advantages, or may be challenged by third parties; ● if enforced, a court may not hold that our patents, if they issue in the future, are valid, enforceable and infringed; ● we may need to initiate litigation or administrative proceedings to enforce and/or defend our patent rights which will be costly whether we win or lose; ● we may choose not to file a patent application in order to maintain certain trade secrets or know-how, and a third party may subsequently file a patent application covering such intellectual property; ● we may fail to adequately protect and police our trademarks and trade secrets; and ● the patents of others may have an adverse effect on our business, including if others obtain patents claiming subject matter similar to or improving that covered by our patent applications. Should any of these or similar events occur, they could significantly harm our business, financial condition, results of operations and prospects. 88 Table of Contents We may be involved in lawsuits to protect or enforce our patents or other intellectual property, which could be expensive, time consuming and unsuccessful. Competitors or other third parties may infringe our patents, trademarks or other intellectual property. To counter infringement or unauthorized use, we or one of our licensing partners may file infringement claims, which can be expensive and time consuming and divert the time and attention of our management and scientific personnel. Our or our licensors’ pending patent applications cannot be enforced against third parties practicing the technology claimed in such applications unless and until a patent issues from such applications. Claims we assert against perceived infringers could provoke these parties to assert counterclaims against us alleging that we infringe their patents, in addition to counterclaims asserting that our patents or our licensors’ patents are invalid or unenforceable, or both. In patent litigation in the U.S., defendant counterclaims alleging invalidity and/or unenforceability are commonplace. Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness, non- enablement, insufficient written description or failure to claim patent-eligible subject matter. Grounds for an unenforceability assertion could be an allegation that someone connected with prosecution of the patent withheld relevant information from the USPTO or made a misleading statement during prosecution. The outcome following legal assertions of invalidity and unenforceability is unpredictable. In any patent infringement proceeding, there is a risk that a court will decide that a patent of ours or our licensors is invalid or unenforceable, in whole or in part, and that we do not have the right to stop the other party from using the invention at issue. There is also a risk that, even if the validity of such patents is upheld, the court will construe the patent’s claims narrowly or decide that we do not have the right to stop the other party from using the invention at issue on the grounds that our or our licensors’ patent claims do not cover the invention, or decide that the other party’s use of our or our licensors’ patented technology falls under the safe harbor to patent infringement under 35 U.S.C. §271(e)(1). An adverse outcome in a litigation or proceeding involving our or our licensors’ patents could limit our ability to assert our or our licensors’ patents against those parties or other competitors and may curtail or preclude our ability to exclude third parties from making and selling similar or competitive products. Any of these occurrences could adversely affect our competitive position, business, financial condition, results of operations or prospects. Similarly, if we assert trademark infringement claims, a court may determine that the marks we have asserted are invalid or unenforceable, or that the party against whom we have asserted trademark infringement has superior rights to the marks in question. In this case, we could ultimately be forced to cease use of such trademarks. Even if we establish infringement, the court may decide not to grant an injunction against further infringing activity and instead award only monetary damages, which may or may not be an adequate remedy. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during litigation. There could also be public announcements of the results of hearings, motions or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could adversely affect the price of shares of our common stock. Moreover, we may not have sufficient financial or other resources to file and pursue such infringement claims, which typically last for years before they are concluded. Even if we ultimately prevail in such claims, the monetary cost of such litigation and the diversion of the attention of our management and scientific personnel could outweigh any benefit we receive as a result of the proceedings. Intellectual property rights of third parties could adversely affect our ability to commercialize obexelimab, or future product candidates, and we, our licensors or collaborators, or any future strategic partners may become subject to third party claims or litigation alleging infringement of patents or other proprietary rights or seeking to invalidate patents or other proprietary rights. We might be required to litigate or obtain licenses from third parties in order to develop or market obexelimab or future product candidates. Such litigation or licenses could be costly or not available on commercially reasonable terms. Our commercial success depends on our ability to develop, manufacture, market and sell our product candidates without infringing, misappropriating or otherwise violating the valid intellectual property and other proprietary rights of third parties. Identifying third-party patent rights that may be relevant to our operations is difficult because patent searching is imperfect due to differences in terminology among patents, incomplete databases and the difficulty in assessing the meaning of patent claims. We cannot guarantee that any of our patent searches or analyses, including the identification of relevant patents, the scope of patent claims or the expiration of relevant patents, are complete or thorough, nor can we be certain that we have identified each and every third-party patent and pending application in the U.S. and abroad that is relevant to or necessary for the commercialization of our product candidates in any jurisdiction. 89 Table of Contents We do not always conduct independent reviews of pending patent applications of and patents issued to third parties. Patent applications in the U.S. and elsewhere are typically published approximately 18 months after the earliest filing for which priority is claimed, with such earliest filing date being commonly referred to as the priority date. Certain U.S. applications that will not be filed outside the U.S. can remain confidential until patents issue. In addition, patent applications in the U.S. and elsewhere can be pending for many years before issuance, or unintentionally abandoned patents or applications can be revived. Furthermore, pending patent applications that have been published can, subject to certain limitations, be later amended in a manner that could cover our product candidates or the use of our product candidates. As such, there may be applications of others now pending or recently revived patents of which we are unaware. The scope of a patent claim is determined by an interpretation of the law, the written disclosure in a patent and the patent’s prosecution history. Our interpretation of the relevance or the scope of a patent or a pending application may be incorrect. For example, we may incorrectly determine that our product candidates are not covered by a third-party patent or may incorrectly predict whether a third-party’s pending application will issue with claims of relevant scope. Our determination of the expiration date of any patent in the U.S. or abroad that we consider relevant may be incorrect. Our failure to identify and correctly interpret relevant patents may negatively impact our ability to develop and market our product candidates. Litigation or other legal proceedings relating to intellectual property claims, with or without merit, is unpredictable and generally expensive and time consuming and, even if resolved in our favor, is likely to divert significant resources from our core business, including distracting our technical and management personnel from their normal responsibilities. In addition, there could be public announcements of the results of hearings, motions or other interim proceedings or developments which could adversely effect the market price of our common stock and harm our reputation. Such litigation or proceedings could substantially increase our operating losses and reduce the resources available for development activities or any future sales, marketing or distribution activities. We may not have sufficient financial or other resources to adequately conduct such litigation or proceedings. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively than we can because of their greater financial resources and more mature and developed intellectual property portfolios. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could adversely affect our ability to compete in the marketplace. There is a substantial amount of intellectual property litigation in the biotechnology and pharmaceutical industries, and we may become party to, or threatened with, litigation or other adversarial proceedings regarding intellectual property rights with respect to our product candidates. We cannot be certain that our product candidates will not infringe existing or future valid patents owned by third parties. Third parties may assert infringement claims against us based on existing or future intellectual property rights, regardless of their merit. We may decide in the future to seek a license to such third-party patents or other intellectual property rights, but we might not be able to do so on reasonable terms. Proving patent invalidity may be difficult. For example, in the U.S., proving invalidity in court requires a showing of clear and convincing evidence to overcome the presumption of validity enjoyed by issued patents. As this burden is a high one, there is no assurance that a court of competent jurisdiction would invalidate the claims of any such U.S. patent or find that our product candidates do not infringe any such claims. If we are found to infringe, misappropriate or otherwise violate a third party’s intellectual property rights, we could be forced, includin