CytomX Therapeutics, Inc. 10-Q

Item 4 Controls and Procedures 31 PART II – OTHER INFORMATION Item 1. Legal Proceedings 32 Item 1A. Risk Factors 32 Item 2. Unregistered Sales of Equity Securities and Use of Proceeds 73 Item 3. Defaults Upon Senior Securities 74 Item 4. Mine Safety Disclosures 74 Item 5. Other Information 74 Item 6. Exhibits 75 Signatures 76 1 Forward-Looking Statements This Quarterly Report on Form 10-Q contains certain forward-looking statements that involve risks and uncertainties. These forward-looking statements reflect our current views with respect to, among other things, future events and our financial performance. These statements are often, but not always, made through the use of words or phrases such as “may,” “might,” “should,” “could,” “predict,” “potential,” “believe,” “expect,” “continue,” “will,” “anticipate,” “seek,” “estimate,” “intend,” “plan,” “projection,” “would,” “annualized” and “outlook,” or the negative version of those words or other comparable words or phrases of a future or forward-looking nature. These forward-looking statements are not historical facts, and are based on current expectations, estimates and projections about our industry, management’s beliefs and certain assumptions made by management, many of which, by their nature, are inherently uncertain and beyond our control. Accordingly, we caution you that any such forward-looking statements are not guarantees of future performance and are subject to risks, assumptions, estimates and uncertainties that are difficult to predict. Although we believe that the expectations reflected in these forward-looking statements are reasonable as of the date made, actual results may prove to be materially different from the results expressed or implied by the forward-looking statements. A number of important factors could cause our actual results to differ materially from those indicated in these forward-looking statements, including those factors identified in “Risk Factors” or “Management’s Discussion and Analysis of Financial Condition and Results of Operations” or the following: • our expectations regarding the potential benefits, activity, effectiveness and safety of our product candidates and therapeutics developed utilizing our PROBODY® conditionally activated platform technology; • the initiation, timing, progress and results of our ongoing clinical trials, research and development programs, preclinical studies, and Investigational New Drug Application (“IND”), Clinical Trial Application, New Drug Application (“NDA”), Biologics License Application (“BLA”), and other regulatory submissions; • the timing of the completion of our ongoing clinical trials and the timing and availability of clinical data from such clinical trials; • our ability to identify and develop additional product candidates; • our dependence on collaborators for developing, obtaining regulatory approval for and commercializing product candidates in the collaboration; • our or a collaborator’s ability to obtain and maintain regulatory approval of any of our product candidates; • our receipt and timing of any milestone payments or royalties under any research collaboration and license agreements or arrangements; • our expectations and beliefs regarding the evolution of the market for cancer therapies and development of the oncology industry; • the rate and degree of market acceptance of any approved product candidates; • the commercialization of any approved product candidates; • our ability to establish and maintain collaborations and retain commercial rights for our product candidates in such collaborations; • the implementation of our business model and strategic plans for our business, technologies and product candidates; • our estimates of our expenses, ongoing losses, future revenue and capital requirements; • our or any collaborator’s ability to obtain and maintain intellectual property protection for our technologies and product candidates and our ability to operate our business without infringing the intellectual property rights of others; • our reliance on third parties to conduct our preclinical studies or any future clinical trials; • our reliance on third-party supply and manufacturing partners to supply the materials and components for, and manufacture, our research and development, preclinical and clinical trial product supplies, including third parties in Europe and China; • our ability to attract and retain qualified key management and technical personnel; • our ability to secure and maintain licenses of intellectual property to protect our technologies and product candidates; • our financial performance; 2 • developments relating to our competitors, our industry, international conflict or uncertainties; and • the extent to which any future pandemic and related governmental regulations and restrictions may impact our business, including our research, clinical trials, which include ongoing site initiation and patient enrollment, manufacturing and financial condition. Any forward-looking statements in this Quarterly Report on Form 10-Q reflect our current views with respect to future events or to our future financial performance and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. Factors that may cause actual results to differ materially from current expectations include, among other things, those listed under Part II, Item 1A. Risk Factors and discussed elsewhere in this Quarterly Report on Form 10-Q. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future. This Quarterly Report on Form 10-Q also contains estimates, projections and other information concerning our industry, our business and the markets for certain drugs and therapeutic biologics, including data regarding the estimated size of those markets, their projected growth rates and the incidence of certain medical conditions. Information that is based on estimates, forecasts, projections or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained these industry, business, market and other data from reports, research surveys, studies and similar data prepared by third parties, industry, medical and general publications, government data and similar sources. In some cases, we do not expressly refer to the sources from which these data are derived. Except where the context otherwise requires, in this Quarterly Report on Form 10-Q, “we,” “us,” “our” and the “Company” refer to CytomX Therapeutics, Inc. Trademarks This Quarterly Report on Form 10-Q includes trademarks, service marks and trade names owned by us or other companies. All trademarks, service marks and trade names included in this Quarterly Report on Form 10-Q are the property of their respective owners. 3 PART I – FINANCIAL INFORMATION Item 1. Condensed Financi al Statements (Unaudited) CYTOMX THERAPEUTICS, INC. CONDENSED BAL ANCE SHEETS (in thousands) September 30, December 31, 2025 2024 (unaudited) (1) Assets Current assets: Cash and cash equivalents $ 34,185 $ 38,052 Short-term investments 109,441 62,571 Accounts receivable 1,629 3,103 Prepaid expenses and other current assets 3,962 3,579 Total current assets 149,217 107,305 Property and equipment, net 1,721 2,467 Intangible assets, net 474 583 Goodwill 949 949 Restricted cash 1,028 1,027 Operating lease right-of-use asset 4,814 8,136 Other assets 51 66 Total assets $ 158,254 $ 120,533 Liabilities and Stockholders' Equity (Deficit) Current liabilities: Accounts payable $ 646 $ 1,088 Accrued liabilities 12,408 12,338 Operating lease liabilities - short term 5,596 5,145 Deferred revenue, current portion 22,379 67,201 Total current liabilities 41,029 85,772 Deferred revenue, net of current portion 5,537 26,862 Operating lease liabilities - long term — 4,240 Other long term liabilities 4,299 4,115 Total liabilities 50,865 120,989 Commitments and contingencies Stockholders' equity (deficit): Convertible preferred stock — — Common stock 2 1 Additional paid-in capital 789,720 691,095 Accumulated other comprehensive income 104 27 Accumulated deficit ( 682,437 ) ( 691,579 ) Total stockholders' equity (deficit) 107,389 ( 456 ) Total liabilities and stockholders' equity (deficit) $ 158,254 $ 120,533 __________________ (1) The condensed balance sheet as of December 31, 2024 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2024. See accompanying notes to condensed financial statements. 4 CYTOMX THERAPEUTICS, INC. CONDENSED STATEMENTS OF OPERA TIONS AND COMPREHENSIVE INCOME (LOSS) (in thousands, except share and per share data) (Unaudited) Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 Revenues $ 5,963 $ 33,432 $ 75,538 $ 100,010 Operating expenses: Research and development 15,304 21,368 47,493 68,592 General and administrative 6,427 7,953 22,477 24,102 Total operating expenses 21,731 29,321 69,970 92,694 Income (loss) from operations ( 15,768 ) 4,111 5,568 7,316 Interest income 1,592 1,693 3,725 5,858 Other (expense) income, net 5 ( 7 ) 33 ( 19 ) Income (loss) before income taxes ( 14,171 ) 5,797 9,326 13,155 Provision for income taxes 58 61 184 162 Net Income (Loss) ( 14,229 ) 5,736 9,142 12,993 Other comprehensive income (loss): Unrealized (loss) gain on investments, net of tax 71 44 77 ( 55 ) Total comprehensive income (loss) $ ( 14,158 ) $ 5,780 $ 9,219 $ 12,938 Net income (loss) per share: Basic $ ( 0.09 ) $ 0.07 $ 0.07 $ 0.15 Diluted $ ( 0.09 ) $ 0.07 $ 0.07 $ 0.15 Weighted average common shares used to compute net income (loss) per share Basic 165,004,291 85,093,227 127,352,366 84,005,093 Diluted 165,004,291 85,204,709 128,859,852 84,428,843 See accompanying notes to condensed financial statements. 5 CYTOMX THERAPEUTICS, INC. CONDENSED STATEMENTS OF STOC KHOLDERS’ EQUITY (DEFICIT) (in thousands, except share data) (Unaudited) Accumulated Additional Other Total Common Stock Paid-in Comprehensive Accumulated Stockholders' Shares Amount Capital Income (Loss) Deficit Equity (Deficit) Balance at December 31, 2024 80,099,889 $ 1 $ 691,095 $ 27 $ ( 691,579 ) $ ( 456 ) Exercise of stock options and release of RSUs 521,404 — — — — — Stock-based compensation — — 2,008 — — 2,008 Other comprehensive loss — — — ( 28 ) — ( 28 ) Net income — — — — 23,525 23,525 Balance at March 31, 2025 80,621,293 $ 1 $ 693,103 $ ( 1 ) $ ( 668,054 ) $ 25,049 Exercise of stock options and release of RSUs 332,741 — 76 — — 76 Issuance of common stock under the ESPP 110,974 — 101 — — 101 Issuance of common stock in follow-on offering, net of issuance cost 76,923,076 1 93,372 — — 93,373 Exercise of pre-funded warrants 6,923,031 — — — — — Stock-based compensation 1,431 — 1,431 Other comprehensive income — — — 34 — 34 Net loss — — — — ( 154 ) ( 154 ) Balance at June 30, 2025 164,911,115 $ 2 $ 788,083 33 $ ( 668,208 ) 119,910 Exercise of stock options 158,532 — 253 — — 253 Stock-based compensation — — 1,384 — — 1,384 Other comprehensive income — — — 71 — 71 Net loss — — — — ( 14,229 ) ( 14,229 ) Balance at September 30, 2025 165,069,647 $ 2 $ 789,720 $ 104 $ ( 682,437 ) $ 107,389 See accompanying notes to condensed financial statements. 6 CYTOMX THERAPEUTICS, INC. CONDENSED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT) (in thousands, except share data) (Unaudited) Accumulated Additional Other Total Common Stock Paid-in Comprehensive Accumulated Stockholders' Shares Amount Capital Income (Loss) Deficit Deficit Balance at December 31, 2023 67,310,838 $ 1 $ 675,905 $ 95 $ ( 723,448 ) $ ( 47,447 ) Exercise of stock options and release of RSUs 826,797 — 174 — — 174 Stock-based compensation — — 1,907 — — 1,907 Other comprehensive loss — — — ( 105 ) — ( 105 ) Net income — — — — 13,791 13,791 Balance at March 31, 2024 68,137,635 $ 1 $ 677,986 $ ( 10 ) $ ( 709,657 ) $ ( 31,680 ) Exercise of stock options and release of RSUs 12,477 — 20 — — 20 Issuance of common stock under the ESPP 196,930 — 236 — — 236 Issuance of common stock under the Open Market Sale Agreement, net of issuance cost 2,270,608 — 4,843 — — 4,843 Exercise of pre-funded warrants 7,499,951 — — — — — Stock-based compensation — — 1,882 — — 1,882 Other comprehensive income — — — 6 — 6 Net loss — — — — ( 6,534 ) ( 6,534 ) Balance at June 30, 2024 78,117,601 $ 1 $ 684,967 $ ( 4 ) $ ( 716,191 ) $ ( 31,227 ) Release of RSUs 115,000 — — — — — Stock-based compensation — — 1,995 — — 1,995 Other comprehensive income — — — 44 — 44 Net income — — — — 5,736 5,736 Balance at September 30, 2024 78,232,601 $ 1 $ 686,962 $ 40 $ ( 710,455 ) $ ( 23,452 ) See accompanying notes to condensed financial statements. 7 CYTOMX THERAPEUTICS, INC. CONDENSED STATEMEN TS OF CASH FLOWS (in thousands) (Unaudited) Nine Months Ended September 30, 2025 2024 Cash flows from operating activities: Net income $ 9,142 $ 12,993 Adjustments to reconcile net income to net cash used in operating activities: Amortization of intangible assets 109 109 Depreciation and amortization 757 1,246 Accretion of discounts on short-term investments ( 1,487 ) ( 4,524 ) Stock-based compensation expense 4,823 5,784 Non-cash lease expense 3,322 3,027 Changes in operating assets and liabilities Accounts receivable 1,474 80 Prepaid expenses and other assets ( 368 ) 1,768 Accounts payable ( 434 ) ( 36 ) Accrued liabilities and other long-term liabilities ( 3,535 ) ( 4,074 ) Deferred revenue ( 66,147 ) ( 82,696 ) Net cash used in operating activities ( 52,344 ) ( 66,323 ) Cash flows from investing activities: Purchases of property and equipment ( 19 ) ( 230 ) Purchases of short-term investments ( 148,306 ) ( 105,706 ) Maturities of short-term investments 103,000 190,501 Net cash (used in) provided by investing activities ( 45,325 ) 84,565 Cash flows from financing activities: Proceeds from issuance of common stock, net of issuance costs 93,373 4,843 Proceeds from employee purchase plan and exercise of stock options 430 430 Net cash provided by financing activities 93,803 5,273 Net (decrease) increase in cash, cash equivalents and restricted cash ( 3,866 ) 23,515 Cash, cash equivalents and restricted cash, beginning of period 39,079 18,088 Cash, cash equivalents and restricted cash, end of period $ 35,213 $ 41,603 See accompanying notes to condensed financial statements. 8 Notes to Condensed Financial Statements (Unaudited) 1. Descriptio n of the Business CytomX Therapeutics, Inc. (the “Company”) is a clinical-stage, oncology-focused biopharmaceutical company developing potent biologics designed to remain masked and inactive in healthy tissue and to be unmasked and preferentially activated in the tumor microenvironment. The Company aims to build a commercial enterprise to maximize its impact on the treatment of cancer. The Company is advancing potential first-in-class and best-in-class therapeutics created using its PROBODY® therapeutic technology platform that could meaningfully improve outcomes for cancer patients. Its proprietary and unique PROBODY technology platform is designed to enable “conditional activation” of masked drug candidates in the tumor microenvironment across multiple therapeutic modalities. The Company is located in South San Francisco, California and was incorporated in the state of Delaware in September 2010. 2. Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation The accompanying interim condensed financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Unaudited Interim Financial Information The accompanying interim condensed financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented. The condensed results of operations for this interim period are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period. The accompanying condensed financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC. Use of Estimates The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. Significant Accounting Policie s There have been no material changes to our significant accounting policies this interim period, as compared to the significant accounting policies disclosed in “Note 2. Basis of Presentation and Summary of Significant Accounting Policies” of the “Notes to Financial Statements” included in Part II, Item 8 of our 2024 Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC. Recently Issued Accounting Standards Not Yet Adopted In November 2024, the Financial Accounting Standards Board (“FASB”) issued Accounts Standards Update (“ASU”) 2024-03, Disaggregation of Income Statement Expenses ("ASU 2024-03"), which enhances transparency in income statement disclosures. ASU 2024-03 requires entities to disclose detailed information about specific components of income statement expenses, such as employee compensation, depreciation, and amortization, as well as other significant expense categories. The objective is to provide financial statement users with greater insight into the nature and variability of expenses, improving their ability to analyze financial performance and make informed decisions. ASU 2025-01 clarified that this ASU 2024-03 is effective for the annual reporting periods beginning after December 15, 2026 and for interim periods within annual reporting periods beginning after December 15, 2027 with early adoption permitted. The Company expects to adopt this ASU during the year ended December 31, 2027 on a prospective basis and is currently evaluating the impact on its financial statements. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures ("ASU 2023-09"), which enhances transparency in income tax disclosures. ASU 2023-09 requires entities to disclose (1) specific categories in the rate reconciliation, (2) the income or loss from continuing operations before income tax expense or benefit (separated between domestic and foreign) and (3) income tax expense or benefit from continuing operations (separated by federal, state and foreign). ASU 2023-09 also 9 Notes to Condensed Financial Statements (Unaudited) requires entities to disclose their income tax payments to international, federal, state and local jurisdictions, among other changes. The Company will adopt this ASU as of December 31, 2025 on a prospective basis and is currently evaluating the impact on its financial statement s. 3. Net Income Per Share Basic net income (loss) per share is calculated by dividing the net income (loss) by the weighted-average number of shares of common stock outstanding for the period. Diluted net income (loss) per share is calculated using the weighted-average number of common shares outstanding, plus potential dilutive common stock during the period. Diluted net loss per share is the same as basic net loss per share in the period when the effect of the potentially dilutive securities is anti-dilutive. The pre-funded warrants are included in both the basic and diluted EPS calculation. The following table presents the calculation of basic and diluted net income per share: Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 (in thousands, except share and per share data) Numerator: Net income (loss) $ ( 14,229 ) $ 5,736 $ 9,142 $ 12,993 Denominator: Basic Weighted-average common shares outstanding 165,004,291 78,170,101 127,352,366 77,081,967 Weighted-average pre-funded warrants — 6,923,126 — 6,923,126 Weighted-average common shares outstanding used to calculate basic net income (loss) per share 165,004,291 85,093,227 127,352,366 84,005,093 Diluted Weighted-average common shares outstanding used to calculate basic net income (loss) per share 165,004,291 85,093,227 127,352,366 84,005,093 Effect of potentially dilutive securities: Stock options, ESPP & RSUs — 111,482 1,507,486 423,750 Weighted-average common shares outstanding used to calculate diluted net income (loss) per share 165,004,291 85,204,709 128,859,852 84,428,843 Net income (loss) per share Basic $ ( 0.09 ) $ 0.07 $ 0.07 $ 0.15 Diluted $ ( 0.09 ) $ 0.07 $ 0.07 $ 0.15 The following weighted-average outstanding shares of potentially dilutive securities are excluded from the computation of diluted net income (loss) per share for the periods presented, because including them would have been anti-dilutive: Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 Options and ESPP to purchase common stock 15,984,069 14,583,619 13,584,042 14,262,791 Common stock warrants 5,769,231 11,538,462 9,615,385 11,538,462 RSUs 2,908,581 1,738,213 122,103 217,727 Total 24,661,881 27,860,294 23,321,529 26,018,980 4. Fair Value Measurements and Investments The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows: 10 Notes to Condensed Financial Statements (Unaudited) • Level I: Inputs which include quoted prices in active markets for identical assets and liabilities. • Level II: Inputs other than Level I that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. • Level III: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The carrying amounts of the Company’s financial instruments, including restricted cash, accounts receivable, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities. The Company’s financial instruments consist of Level I and Level II assets which consist primarily of highly liquid money market funds, some of which are included in restricted cash and U.S. Treasury securities that are included in cash equivalents or short-term investments. Our Level II marketable securities are valued using third-party pricing sources, which can include observable market prices, interest rates and yield curves observable at commonly quoted intervals for similar assets as observable inputs for pricing. The following tables set forth the fair value of the Company’s investments subject to fair value measurements on a recurring basis and the level of inputs used in such measurements: September 30, 2025 Valuation Hierarchy Amortized Cost Gross Unrealized Gains Aggregate Fair Value (in thousands) Assets Money market funds Level I $ 19,269 $ — $ 19,269 Restricted cash (money market funds) Level I 1,028 — 1,028 U.S. Treasury Securities Level II 124,300 103 124,403 Total $ 144,597 $ 103 $ 144,700 December 31, 2024 Valuation Hierarchy Amortized Cost Gross Unrealized Gains Aggregate Fair Value (in thousands) Assets Money market funds Level I $ 28,313 $ — $ 28,313 Restricted cash (money market funds) Level I 1,027 — 1,027 U.S. Treasury Securities Level II 72,503 27 72,530 Total $ 101,843 $ 27 $ 101,870 As of September 30, 2025, the remaining contractual terms of those investments are less than a year. Based on the scheduled maturities of our marketable securities, we determined that it was more likely than not that we will hold these marketable securities to maturity for a recovery of our cost basis. 5. Accrued Liabilities Accrued liabilities consisted of the following: September 30, December 31, 2025 2024 (in thousands) Research and clinical expenses $ 4,827 $ 8,581 Payroll and related expenses 6,419 2,578 Legal and professional expenses 735 689 Restructuring expenses 86 — Other accrued expenses 341 490 Total $ 12,408 $ 12,338 11 Notes to Condensed Financial Statements (Unaudited) 6. Collaboration and License Agreements The following table summarizes the revenue by collaboration partner: Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 (in thousands) (in thousands) Amgen $ — $ ( 783 ) $ 9,818 $ 1,491 Astellas 4,360 2,553 18,453 23,497 Bristol Myers Squibb — 22,977 41,928 56,042 Regeneron 1,600 2,896 5,307 7,925 Moderna 3 5,789 32 11,055 Total revenue $ 5,963 $ 33,432 $ 75,538 $ 100,010 Amgen, Inc. On September 29, 2017, the Company and Amgen, Inc. (“Amgen”) entered into a Collaboration and License Agreement (the “Amgen Agreement”). Pursuant to the Amgen Agreement, the Company received an upfront payment of $ 40.0 million in October 2017. Concurrent with the Amgen Agreement, the Company and Amgen entered into a Share Purchase Agreement pursuant to which Amgen purchased 1,156,069 shares of the Company’s common stock at a price of $ 17.30 per share for total proceeds of $ 20.0 million. Under the terms of the Amgen Agreement, as amended, the Company and Amgen were co-developing a conditionally activated T-cell engager (“TCE”) targeting epidermal growth factor receptor (the “EGFR Products”). The Company was responsible for early-stage development of EGFR Products and Amgen was to be responsible for late-stage development and commercialization of EGFR Products. Following potential advancement beyond early-stage development, the Company had the right to elect to participate financially in the global co-development of EGFR Products with Amgen, during which the Company would have been responsible for a certain percentage of the worldwide development costs and entitled to certain percentage of profit sharing in the U.S., for EGFR Products. In addition, the Company was also eligible to receive up to $ 460.0 million in development, regulatory, and commercial milestone payments for EGFR Products, and royalties in certain percentages of worldwide commercial sales. In October 2021, CytomX and Amgen executed an amendment to the Amgen Agreement primarily to (1) extend the target selection date for Amgen to select its additional targets for research and development, and (2) reduce the total number of milestone events and increase the total amount of milestone payments for EGFR Products. In each of May 2023 and March 2024, CytomX and Amgen executed an amendment to the Amgen Agreement to extend the target selection period for Amgen to select its additional targets. Amgen had the right to select a total of up to three targets, including the two additional targets. The Company and Amgen collaborated in the research and development of conditionally activated T-cell engaging bispecifics therapies directed against such targets. Amgen had selected one such target (the “Amgen Other Product”). Except with respect to preclinical activities to be conducted by CytomX, Amgen would have been responsible, at its expense, for the development, manufacture, and commercialization of all Amgen Products. In January 2022, the IND for the EGFR product (CX-904) was allowed to proceed by the U.S. Food and Drug Administration (“FDA”) and the program progressed into Phase 1 dose escalation. In March 2025, CytomX and Amgen jointly decided to not continue CX-904 development and Amgen terminated its license to the EGFR Products. In April 2025, the Amgen Other Product was also terminated with 60 days written notice pursuant to the Amgen Agreement. A cumulative adjustment from a change in estimate of $ 8.4 million was recognized in the first quarter of 2025 due to Amgen terminating its license to the EGFR Product effective May 2025. The Amgen research collaboration remains in effect with the current scope being the preclinical TCE that CytomX selected from Amgen’s preclinical pipeline further discussed below. At the initiation of the collaboration, CytomX had the option to select from programs specified in the Amgen Agreement, an existing preclinical stage TCE product from the Amgen preclinical pipeline. In March 2018, CytomX selected the program and this program, CX-908, a PROBODY® T cell engager targeting CDH3 and CD3, is currently in preclinical development. CytomX is responsible, at its expense, for converting this program to a conditionally activated TCE product, and thereafter, will be responsible for development, manufacturing, and commercialization of the product (“CytomX Product”). Amgen is eligible to receive up to $ 203.0 million in development, regulatory, and commercial milestone payments for the CytomX Product, and tiered mid-single digit to low double-digit percentage royalties. 12 Notes to Condensed Financial Statements (Unaudited) As of June 30, 2025, the Company has completed its performance obligations related to the EGFR Products and the Amgen Other Products. The remaining deferred revenue of $ 0.3 million was fully recognized in the second quarter of 2025. As of December 31, 2024, deferred revenues related to the EGFR Products performance obligation was $ 9.7 million and was immaterial for the Amgen Other Products. Astellas Pharma Inc. The Company and Astellas Pharma, Inc. (“Astellas”) entered into a Collaboration and License Agreement (the “Astellas Agreement”) on March 23, 2020, the effective date, to collaborate on preclinical research activities to discover and develop certain antibody compounds for the treatment of cancer using the Company’s PROBODY therapeutic technology. Under the terms of the Astellas Agreement, the Company granted Astellas an exclusive, worldwide right to develop and commercialize PROBODY therapeutics for up to four collaboration targets including one initial target and three additional targets (“Additional Targets”). In addition, Astellas had the right to expand the number of Additional Targets from three up to five (the “Expansion Option”) before the third anniversary of the effective date. Furthermore, for a specified number of targets, at a pre-specified time prior to the initiation of the first pivotal study of a product against such target, the Company may elect to participate in certain development costs and share in the profits generated in the United States with respect to such product (“Cost Share Option”). The Cost Share Option, if exercised, will also provide the option for the Company to co-commercialize such product in the United States. The Company does not consider the Cost Share Option as a performance obligation at the inception of the agreement as participation is at the Company’s discretion. Pursuant to the Astellas Agreement, the consideration from Astellas was comprised of an upfront fee of $ 80.0 million and total potential contingent payments for development, regulatory and sales milestones of up to an aggregate of approximately $ 1.6 billion. The Company is also entitled to tiered royalties from high-single digit to mid-teen percentage royalties from potential future sales. Astellas is responsible for all preclinical research costs incurred by either party as set forth in the preclinical research plan and the Company will receive research and development service fees based on a prescribed full-time employee ("FTE") rate. In January 2023, the Company announced that it achieved a clinical candidate milestone under the Astellas Agreement which triggered a $ 5.0 million milestone payment to the Company which was fully recognized in the first quarter of 2023 as the Company had completed its related performance obligation of the first collaboration target which resulted in the clinical candidate nomination for further development. In March 2024, the Company announced that it achieved the good laboratory practices ("GLPs") toxicology milestone for this candidate which triggered a $ 5.0 million milestone payment to the Company. The $ 5.0 million milestone payment was fully recognized in the first quarter of 2024 as the Company had completed its related performance obligation of this first collaboration target. Also, in March 2024, the Company announced that it achieved a clinical candidate milestone for a second collaboration target under the Astellas Agreement which triggered an additional $ 5.0 million milestone payment to the Company. The $ 5.0 million milestone payment was fully recognized in the first quarter of 2024 as the Company had completed its related performance obligation of the second collaboration target which resulted in the clinical candidate nomination for further development. In the first quarter of 2025, Astellas initiated GLP toxicology studies for the second collaboration target, triggering a $ 5.0 million milestone payment to CytomX. The $ 5.0 million milestone payment was fully recognized in the first quarter of 2025 as the Company had completed its related performance obligation of this second collaboration target. As of September 30, 2025 and December 31, 2024, deferred revenue relating to the Astellas Agreement was $ 7.2 million and $ 17.4 million, respectively. The amount due from Astellas under the Astellas Agreement was $ 1.1 million as of September 30, 2025 and $ 1.1 million as of December 31, 2024. Bristol Myers Squibb Company On May 23, 2014, the Company and Bristol Myers Squibb Company (“Bristol Myers Squibb” or “BMS”) entered into a Collaboration and License Agreement (the “BMS Agreement”) to discover and develop compounds for use in human therapeutics aimed at multiple immuno-oncology targets using the Company’s PROBODY therapeutic technology, including the target CTLA-4. The effective date of the BMS Agreement was July 7, 2014. Under the terms of the BMS Agreement, the Company granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize PROBODY therapeutics for up to four oncology targets. Bristol Myers Squibb had additional rights to substitute up to two collaboration targets within three years of the effective date of the BMS Agreement. These rights expired in May 2017. Each collaboration target had a two-year research term and the two additional targets had to be nominated by Bristol Myers Squibb within five years of the effective date of the BMS Agreement. The research term for each collaboration target could be extended in one year increments up to three times. 13 Notes to Condensed Financial Statements (Unaudited) Pursuant to the BMS Agreement, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $ 50.0 million and estimated research and development service fees, and the Company was initially entitled to receive contingent payments of up to $ 25.0 million for additional targets and contingent payments for development, regulatory and sales milestones. In addition, the Company was entitled to royalty payments in the mid-single digits to low double-digit percentages from potential future sales. On March 17, 2017, the Company and Bristol Myers Squibb amended the BMS Agreement and entered into Amendment Number 1 to Extend Collaboration and License Agreement (“Amendment 1”). Amendment 1 granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize PROBODY therapeutics for up to eight additional targets. The effective date of Amendment 1 was April 25, 2017. Under the terms of Amendment 1, the Company continued to have obligations to Bristol Myers Squibb to discover and conduct preclinical development of PROBODY therapeutics against any targets they chose to select during the research period under the terms of Amendment 1. Pursuant to Amendment 1, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $ 200.0 million, estimated research and development service fees, and contingent payments for development, regulatory and sales milestones for the eight targets. The Company was also entitled to tiered mid-single to low double-digit percentage royalties from potential future sales. Amendment 1 did not change the term of Bristol Myers Squibb’s royalty obligation under the BMS Agreement. Bristol Myers Squibb’s royalty obligation continues on a licensed-product by licensed-product basis until the later of (i) the expiration of the last claim of the licensed patents covering the licensed products in the country, (ii) the twelfth anniversary of the first commercial sale of a licensed product in a country, or (iii) the expiration of any applicable regulatory, pediatric, orphan drug or data exclusivity with respect to such product. In February 2021, the Company and Bristol Myers Squibb amended the BMS Agreement and entered into Amendment Number 2 to amend the Collaboration and License Agreement (“Amendment 2”), as previously amended by Amendment 1. Subsequent to Amendment 2, in addition to Bristol Myers Squibb’s ongoing development of the CTLA-4 program, Bristol Myers Squibb also had the exclusive worldwide rights to develop and commercialize PROBODY therapeutics for up to five oncology targets. Under the terms of Amendment 2, the period for target selection was extended and in 2022, all remaining targets were selected. The Company continues to collaborate with Bristol Myers Squibb to discover and conduct preclinical development of PROBODY therapeutics against targets selected by Bristol Myers Squibb over the estimated research period, which is projected to end in April 2025. Pursuant to Amendment 2, the Company was eligible to receive contingent payments for development, regulatory and sales milestones. It is also entitled to tiered mid-single to low double-digit percentage of royalties from potential future sales. The Company accounted for Amendment 2 as a modification and reallocated the remaining unrecognized transaction price to the remaining performance obligations. In October 2022, the Company and Bristol Myers Squibb amended the BMS Agreement and entered into Amendment Number 3 (“Amendment 3”), as previously amended by Amendment 1 and Amendment 2, to clarify the rights and restrictions of certain new proprietary antibodies that the parties exchanged. There were no substantive changes to each party's performance obligations. In March 2024, following a Bristol Myers Squibb corporate portfolio prioritization process, Bristol Myers Squibb notified CytomX that it does not intend to continue the development of BMS-986288 beyond the current Phase 2 study and terminated its collaboration license to the CTLA-4 target under the collaboration. BMS-986288 was Bristol Myers Squibb’s leading next generation PROBODY CTLA-4 program that it had previously prioritized over BMS-986249, which was a PROBODY version of ipilimumab. In June 2024, Bristol Myers Squibb prioritized its pre-clinical research activities under the collaboration and revised the research scope by one collaboration target. The Company determined that it has no further obligations related to the target that was deprioritized and accounted for the reduction of the target as a modification and the related remaining unrecognized transaction price was reallocated to the remaining performance obligations. As of December 31, 2024, deferred revenue relating to BMS Agreement was $ 41.9 million. T he Company's research efforts on all the ongoing programs were completed in April 2025 upon which the $ 11.6 million of remaining deferred revenue was recognized in the second quarter of 2025. In May 2025, one collaboration target was also terminated with two months written notice pursuant to the BMS Agreement and two preclinical programs remain in development with Bristol Myers Squibb responsible for further advancement. ModernaTX, Inc. The Company and ModernaTX, Inc. (“Moderna”) entered into a Collaboration and License Agreement (the “Moderna Agreement”) on December 30, 2022, the effective date, to collaborate on discovery and preclinical research and development activities to create investigational messenger RNA (mRNA) based conditionally activated therapies using the Company’s PROBODY therapeutic technology. Moderna is solely responsible for the development (preclinical and clinical), manufacturing, and commercialization of any products under the Moderna Agreement. 14 Notes to Condensed Financial Statements (Unaudited) Under the terms of the Moderna Agreement, the Company granted Moderna an exclusive, worldwide right to develop and commercialize PROBODY therapeutics for the collaboration programs. In exchange, the Company received an upfront payment of $ 35.0 million in January 2023, including $ 5.0 million of prepaid research and development service fees. The Company will continue to receive research and development service fees according to the preclinical research work plans based on a prescribed FTE rate and is eligible to receive up to approximately $ 1.2 billion in future development, regulatory, and commercial milestone payments. The Company is also eligible to receive tiered royalties from high-single digit to low-teen percentage rates of annual global net sales of any products that are commercialized under the Moderna Agreement. Due to Moderna's budget considerations in 2025, the Company's remaining activities for its performance obligation are currently expected to be carried out primarily in 2026 and 2027. As of September 30, 2025 and December 31, 2024, deferred revenue relating to the Moderna Agreement was $ 9.3 million and $ 9.3 million, respectively. The amount due from Moderna under the Moderna Agreement was $ 0.0 and $ 0.9 million as of September 30, 2025 and December 31, 2024, respectively. Regeneron Pharmaceuticals, Inc. The Company and Regeneron Pharmaceuticals Inc. (“Regeneron”) entered into a Collaboration and License Agreement (the “Regeneron Agreement”) on November 16, 2022, to collaborate on creation of conditionally-activated investigational bispecific cancer therapies utilizing the Company’s PROBODY therapeutic platform and Regeneron’s Veloci-Bi® bispecific antibody development platform. The Company and Regeneron will collaborate on preclinical research and discovery activities for initially agreed upon collaboration programs (“Collaboration Program”) with an option to expand additional Collaboration Programs (“Additional Collaboration Program Option”). Under the Collaboration and License Agreement, the Company granted Regeneron an exclusive, worldwide, royalty-bearing license under certain Company intellectual property to develop, manufacture, commercialize and otherwise exploit licensed products (“Licensed Products”) for all human and non-human diagnostic, prophylactic and therapeutic uses in oncology. Regeneron is responsible for funding the cost of preclinical research and discovery activities of both parties for all Licensed Products and for funding the cost of development, manufacturing and commercialization of all Licensed Products worldwide. Pursuant to the Regeneron Agreement, the consideration from Regeneron is comprised of an upfront fee of $ 30.0 million, contingent payments for development and regulatory milestones and commercial milestone payments of up to an aggregate of approximately $ 0.8 billion. If Regeneron exercises its Additional Collaboration Program Option, the Company would be eligible to receive additional upfront and milestone payments aggregating up to approximately $ 1.2 billion. The Company is also entitled to tiered royalties from high-single digit to low-teen percentage royalties from potential future sales. In addition, the Company will receive research and development service fees based on a prescribed FTE rate. As of September 30, 2025 and December 31, 2024, deferred revenue relating to the Regeneron Agreement was $ 11.4 million and $ 15.6 million, respectively. The amount due from Regeneron under the Regeneron Agreement was $ 0.4 million and $ 1.0 million as of September 30, 2025 and December 31, 2024, respectively. Contract Liabilities The following table presents changes in the Company’s total contract liabilities during the nine months ended September 30, 2025 and 2024: Deferred Revenue (in thousands) December 31, 2024 $ 94,063 Additions 4,391 Revenue recognized ( 70,538 ) September 30, 2025 $ 27,916 December 31, 2023 $ 212,315 Additions 6,652 Revenue recognized ( 89,348 ) September 30, 2024 $ 129,619 The Company expects that the $ 27.9 million of deferred revenue related to the following contracts as of September 30, 2025 will be recognized as revenue based on actual FTE effort and estimated program progress as set forth below. However, the timing of revenue recognition could differ from the estimates depending on facts and circumstances impacting the various contracts, including progress of 15 Notes to Condensed Financial Statements (Unaudited) research and development, resources assigned to the contracts by the Company or its collaboration partners or other factors outside of the Company’s control. • The $ 7.2 million of deferred revenue related to the Astellas Agreement is expected to be recognized until 2026 . • The $ 9.3 million of deferred revenue related to the Moderna Agreement, together with research and development service fees, is expected to be recognized primarily in 2026 and 2027 due to Moderna's budget considerations in 2025. • The $ 11.4 million o f deferred revenue related to the Regeneron Agreement, together with research and development service fees, is expected to be recognized until 2026 . 7. License Agreement UCSB Agreement In August 2010, the Company entered into an exclusive, worldwide license agreement with University of California, Santa Barbara (“UCSB”), relating to the use of certain patents and technology relating to its core technology, including its therapeutic antibodies, and to certain patent rights the Company co-owns with UCSB covering PROBODY antibodies and other pro-proteins (the “UCSB Agreement”). Pursuant to the UCSB Agreement, the Company has annual minimum royalty obligations of $ 0.2 million under the terms of certain exclusive licensed patent rights. In April 2019, the Company entered into Amendment No.3 to the UCSB Agreement to adjust and clarify certain sublicense terms (“Amendment No.3”). Under the terms of Amendment No.3, the Company agreed to make an additional annual license maintenance fees of $ 0.8 million through 2031 . In the event that the Company terminates the agreement due to material concern of the safety or efficacy of the related technology, 50 % of all remaining maintenance fees will become due immediately. Otherwise, all remaining maintenance fees will become due immediately upon early termination of the agreement unless there is a material breach by UCSB. In March 2024, the Company incurred $ 0.6 million of sublicense fees triggered by achieving the GLP toxicology studies milestone for the first clinical candidate which was nominated by Astellas in 2023, as well as by achieving the clinical candidate nomination milestone for a second collaboration target under the Astellas Agreement. In the first quarter 2025, the Company incurred $ 0.2 million of sublicense fees triggered by achieving the GLP toxicology studies milestone for the second clinical candidate which was nominated by Astellas in March 2024. For the three and nine months ended September 30, 2025, the Company incurred sublicense expenses of $ 0 and $ 1.1 million, r espectively, under the provisions of the UCSB Agreement. For the three and nine months ended September 30, 2024, the Company incurred sublicense expenses of $ 0 and $ 1.6 million, respectively, under the provisions of the UCSB Agreement. ImmunoGen (acquired by AbbVie in 2024) In December 2019, the Company entered into a License Agreement (the “ImmunoGen 2019 License”) with ImmunoGen, Inc. to obtain an exclusive license with respect to epithelial cell adhesion molecule (“EPCAM”). Under the ImmunoGen 2019 License, ImmunoGen agreed to transfer its know-how, patents, intellectual property rights, and technology transfer materials and information related to its EpCAM program. The license gives the Company the sole ability to develop, manufacture, use and commercialize any licensed product that incorporates, is comprised of, or otherwise derived from PROBODY technology that targets EpCAM in any human therapeutic field on a worldwide basis. In exchange, the Company made an upfront license payment of $ 7.5 million, and will pay up to $ 35.0 million in certain clinical development milestones and up to $ 320.0 million in regulatory approval and commercial milestone payments, if achieved. ImmunoGen is also entitled to royalties on product sales ranging from the mid-to-high single digits percentages. In April 2024, the Company made a $ 5.0 million payment of the $ 35.0 million in potential clinical development milestone payments to AbbVie (formerly ImmunoGen) with respect to achieving the milestone of dosing the first patient for CX-2051 under the ImmunoGen 2019 License Agreement. 8. Common Stock In February 2020, the Company entered into the Open Market Sale Agreement (as amended on each of March 4, 2022 and August 9, 2024, the “Sales Agreement”) with Jefferies LLC (“Jefferies”), as sales agent, providing for the sale of up to $ 75,000,000 of its common stock, at par value $ 0.00001 per share, from time to time under an at-the-market ("ATM") offering. Pursuant to the Sales Agreement, Jefferies as the sales agent will receive a commission of 3.0 % of the gross sales price for shares of common stock sold under the Sales Agreement . In 2024, under the ATM offering, the Company sold approximately 3.9 million shares at a weighted average price of $ 1.82 per share for net proceeds of approximately $ 6.9 million after deducting sales commissions and related issuance cost. In Octo ber 2025, the Company sold approximately 4.3 million shares at a weighted average price of $3.43 per share under the ATM offering for net proceeds of approximately $14.4 million, after deducting sales commissions and related issuance cost. 16 Notes to Condensed Financial Statements (Unaudited) In May 2025, the Company completed an underwritten public offering of 76,923,076 shares of common stock at a price of $ 1.30 per share. The aggregate net proceeds received by the Company from the offering were approximately $ 93.4 million, after deducting underwriting discounts and commissions of $ 6.0 milli on and offering expenses of $ 0.6 mil lion. Longitude Venture Partners V, L.P. (“LVPV”) acquired approximately 11.5 million shares of common stock through the underwritten public offering. Longitude Capital Partners V, LLC (“LCPV”) is a general partner of LVPV. A member of the Company’s board of directors serves as a managing director of LCPV, and therefore, LCPV is considered a related party of the Company. The Company had no other significant related party transactions with LCPV. In June 2023, the Company entered into an agreement with BVF Partners L.P. (“BVF”) for a private placement (the "Private Placement Agreement") and received an aggregate net proceeds of approximately $ 29.7 million in July 2023, after deducting issuance costs of approximately $ 0.3 million. In the private placement, the Company issued pre-funded warrants to BVF to purchase up to 14,423,077 shares of common stock, accompanying Tranche 1 warrants to purchase up to 5,769,231 shares of common stock and accompanying Tranche 2 warrants to purchase up to 5,769,231 shares of common stock, at a combined price of $ 2.08 per share. The initial exercise price of the Tranche 1 and Tranche 2 warrants was $ 4.16 per share and $ 6.24 per share, respectively. The public offering in May 2025 triggered an adjustment provision in the Tranche 1 and Tranche 2 warrants, pursuant to which the exercise prices were reduced to $ 2.73 and $ 3.77 per share, respectively. In May 2024, BVF exercised its right to purchase 7.5 million shares of common stock through its pre-funded warrants at an exercise price of $ 0.00001 per share. In May 2025, BVF exercised its right to purchase the remaining 6.9 million shares of common stock through its pre-funded warrants at an exercise price of $ 0.00001 per share. The following table summarizes the Company's activities of outstanding warrants for the nine months ended of September 30, 2025: Pre-funded Warrants Tranche 1 Warrants Tranche 2 Warrants Number of warrants Weighted- Average Exercise Price Per Share Number of warrants Weighted- Average Exercise Price Per Share Number of warrants Weighted- Average Exercise Price Per Share Balance at December 31, 2024 6,923,077 $ 0.00001 5,769,231 $ 4.16 5,769,231 $ 6.24 Exercised ( 6,923,077 ) — — Expired — ( 5,769,231 ) — Balance at September 30, 2025 — $ 0.00001 — $ 2.73 5,769,231 $ 3.77 The Tranche 1 warrants expired without being exercised in July 2025 and the Tranche 2 warrants expire in July 2026 . 9. Stock-Based Compensation Stock Options Activities for the Company’s stock option plans for the nine months ended September 30, 2025 were as follows: Options Outstanding Number of Options Weighted- Average Exercise Price Per Share Balance at December 31, 2024 14,562,061 $ 6.20 Options granted 3,983,805 1.41 Options exercised ( 210,439 ) 1.57 Option forfeited/expired ( 2,158,715 ) 5.55 Balance at September 30, 2025 16,176,712 $ 5.16 The Company recorded $ 0.8 million an d $ 1.5 million of stock-based compensation expense related to the stock option plans for the three months ended September 30, 2025 and 2024, respectively. The Company recorded $ 2.9 million and $ 4.4 million of stock-based compensation expense related to the stock option plans for the nine months ended September 30, 2025 and 2024, respectively. 17 Notes to Condensed Financial Statements (Unaudited) Time-based RSUs ("TRSU") Activities for the Company’s TRSUs for the nine months ended September 30, 2025 were as follows: Number of Shares Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2024 1,853,232 $ 2.00 RSU's awarded 1,998,163 0.86 RSU's vested ( 527,238 ) 2.21 RSU's forfeited ( 419,407 ) 1.89 Balance at September 30, 2025 2,904,750 $ 1.19 The Company recorde d $ 0.5 million and $ 0.4 million of stock-based compensation expense related to the TRSUs for the three months end September 30, 2025 and 2024, respectively. The Company recorded $ 1.1 million a nd $ 1.1 million of stock-based compensation expense related to the TRSUs for the nine months end September 30, 2025 and 2024, respectively. Performance-based RSUs ("PSUs") 2023 PSU In February 2023, the Company granted 760,000 PSUs to executive employees with an aggregated grant date fair value of approximately $ 1.9 million. Vesting for 50% of the PSUs granted occurred upon attaining certain specific milestones by December 2024 (“2023-Tranche-1”), and the remaining 50% will vest upon attaining certain specific milestones by December 2025 (“2023-Tranche-2”). As of December 31, 2024, the PSUs for 2023-Tranche-1 were canceled as the related performance condition was not met by December 2024. The performance condition for 2023-Tranche-2 was determined to be probable a s of March 31, 2025 and as a result $ 0.5 million compensation cost was recorded for the first quarter of 2025. As of June 30, 2025, the performance condition was determined to be satisfied and the 2023-Tranche-2 PSUs were fully vested. As a result, the Company recorded $ 0.2 million and $ 0.7 million compensation cost for the three and six months ended June 30, 2025. 2024 PSU In January 2024, the Company granted 810,000 PSUs to executive employees with an aggregated grant date fair value of approximately $ 1.3 million. Vesting for 50% of the PSUs granted will occur upon attaining certain specific milestones by December 2025 (“2024-Tranche-1”), and the remaining 50% will vest upon attaining certain specific milestones by December 2026 (“2024-Tranche-2”). The Company determined that it is not probable that the performance conditions will be satisfied for each of these tranches and hence no compensation cost was recorded for these awards through September 30, 2025. 2025 PSU In September 2025, the Company granted 413,350 PSUs to executive employees with an aggregated grant date fair value of approximately $ 1.2 million. Vesting for one third of the PSUs granted will occur upon attaining a certain specific milestone (“2025-Tranche-1”), vesting for one third of the PSUs granted will occur upon attaining a certain specific milestone (“2025-Tranche-2”) on June 30, 2027 or later, and the remaining one third will vest upon attaining a certain specific milestone on June 30, 2028 or later (“2025-Tranche-3”). The Company determined that it is not probable that the performance conditions will be satisfied for each of these tranches and hence no compensation cost was recorded for these awards through September 30, 2025. Activities for the Company’s PSUs for the nine months ended September 30, 2025, were as follows: Number of Shares Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2024 1,190,000 $ 1.94 PSU's awarded 413,350 2.90 PSU's vested ( 275,000 ) 2.52 PSU's forfeited ( 330,000 ) 1.95 Balance at September 30, 2025 998,350 $ 2.18 18 Notes to Condensed Financial Statements (Unaudited) Stock-based Compensation Total stock-based compensation recorded was as follows: Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 (in thousands) (in thousands) Research and development $ 597 $ 691 $ 1,723 $ 2,054 General and administrative 787 1,304 3,100 3,730 Total stock-based compensation expense $ 1,384 $ 1,995 $ 4,823 $ 5,784 10. Income Taxes The Company maintains a full valuation allowance against its net deferred tax assets through December 31, 2024 . The Company files income taxes in the U.S. federal jurisdiction, the state of California and various other U.S. states. The state of California contested the Company’s tax position on revenue apportionment for upfront and milestone payments resulting from the Company’s collaboration and licensing agreements for the years 2017 and 2018. In September 2023, the Company received Notice of Proposed Assessment (“NOPA”) from the Franchise Tax Board. The Company recorded an uncertain tax position of $ 4.3 million in long term liabilities for the proposed tax assessment, penalties and interest through September 30, 2025. Of the unrecognized tax benefits as of September 30, 2025, approximately $ 5.0 million would affect the Company’s effective tax rate if recognized. In addition, utilization of carryforward attributes and indirect federal tax effects of the assessment would result in a reduction in deferred tax assets of $ 5.0 million. The Company filed a protest to contest the proposed assessment in November 2023. Due to the ongoing nature of the examination and discussions with the state of California, the Company is unable to estimate a date by which this matter will be resolved. The One Big Beautiful Bill Act (OBBBA) was signed into law in July 2025. The OBBBA may be subject to further clarification and interpretative guidance. The provisions do not have a material impact on the Company’s financial statements . 19 Notes to Condensed Financial Statements (Unaudited) 11. Segment Disclosures The Company operates as a single operating segment. The Chief Executive Officer is identified as the Chief Operating Decision Maker (CODM). The CODM primarily reviews the Company’s financial information on an aggregate basis. The CODM utilizes the aggregated financial information to make strategic decisions, assess performance, and allocate resources across the Company. The aggregate information includes the revenue by collaboration partner, research and development expense by program, as well as net income that is reported on the Condensed Statements of Operations and Comprehensive Income. Net income is used to monitor budget versus actual results in assessing performance of the segment and in establishing management's compensation. The measure of segment assets is reported on the Condensed Balance Sheets as total assets. All of the Company’s long-lived assets are located in the United States. In addition to the revenue by collaborative partners disclosed in Note 6, the CODM reviews the following significant expenses in making decisions about the allocation of resources and assessing performance (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 (in thousands) (in thousands) Total revenue $ 5,963 $ 33,432 $ 75,538 $ 100,010 External costs incurred by product candidate (target): CX-904 (EGFRxCD3) 150 2,659 710 5,847 CX-2051 (EpCAM) 5,354 6,353 13,304 14,105 CX-801 (IFNα2b) 369 456 1,308 2,060 Other wholly owned and partnered programs 462 783 1,357 5,596 General research and development expenses 1,700 2,529 5,750 13,888 Total external costs 8,035 12,780 22,429 41,496 Internal costs 7,269 8,588 25,064 27,096 Research and development expenses 15,304 21,368 47,493 68,592 General and administrative expenses 6,427 7,953 22,477 24,102 Total operating expenses 21,731 29,321 69,970 92,694 Income (loss) from operations ( 15,768 ) 4,111 5,568 7,316 Interest income 1,592 1,693 3,725 5,858 Other income (expense), net 5 ( 7 ) 33 ( 19 ) Income (loss) before income taxes ( 14,171 ) 5,797 9,326 13,155 Provision for income taxes 58 61 184 162 Segment and net income (loss) $ ( 14,229 ) $ 5,736 $ 9,142 $ 12,993 20 Notes to Condensed Financial Statements (Unaudited) 12. Restructuring On January 6, 2025, the Company announced a restructuring plan to streamline its organization and prioritize CX-2051 (EpCAM PROBODY ® ADC), CX-801 and its activities to support its research collaborations. This plan resulted in a reduction of approximately 40 % of its workforce and was substantially completed in the first quarter of 2025. The Company incurred the total restructuring charges of $ 2.8 million, primarily related to one-time severance payments and other employee-related co sts. This includes $ 1.7 million of research and development expenses and $ 1.1 million of general and administrative expenses that were recorded during the nine months ended September 30, 2025. The following is a summary of activities of restructuring costs (in thousands): Severance and Benefits Costs Stock Based Compensation Total Restructuring cost recorded $ 2,833 $ 77 $ 2,910 Cash payment ( 1,974 ) — ( 1,974 ) Changes in estimates ( 4 ) — ( 4 ) Non-cash charges — ( 77 ) ( 77 ) Balance at March 31, 2025 $ 855 $ — $ 855 Restructuring cost 25 25 Cash payment ( 702 ) — ( 702 ) Changes in estimates ( 17 ) — ( 17 ) Balance at June 30, 2025 $ 161 $ — $ 161 Cash payment ( 5 ) — ( 5 ) Changes in estimates ( 70 ) — ( 70 ) Balance at September 30, 2025 $ 86 $ - $ 86 13. Subsequent Event Lease In November 2025, the Company entered into a lease (the “2026 Lease”) of office and laboratory space located in Emeryville, California for the Company’s corporate headquarters. The 2026 Lease will commence on October 1, 2026 and end on December 31, 2029 , and the Company has two options to extend the term, each for an additional two years , at the then fair market rent as determined under the term of the 2026 Lease. Under the terms of the lease, the Company is obligated to make aggregate future minimum lease payments totaling approximately $5.7 million over the lease term, exclusive of operating expenses and other common area charges. 21 Item 2. Management’s Discuss ion and Analysis of Financial Condition and Results of Operations You should read the following management’s discussion and analysis of our financial condition and results of operations in conjunction with our unaudited condensed financial statements and notes thereto included in Part I, Item 1 of this Quarterly Report on Form 10-Q and with our audited financial statements and notes thereto for the year ended December 31, 2024, included in our Annual Report on Form 10-K as filed with the U.S. Securities and Exchange Commission (“SEC”) on March 6, 2025. This discussion and other parts of this report contain forward-looking statements that involve risks and uncertainties, such as statements of our plans, objectives, expectations and intentions. Our actual results could differ materially from those discussed in these forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, those discussed in the section of this report titled “Risk Factors.” Except as may be required by law, we assume no obligation to update these forward-looking statements or the reasons that results could differ from these forward-looking statements. Overview We are a clinical-stage, oncology-focused biopharmaceutical company focused on developing novel, conditionally activated, masked biologics designed to be preferentially unmasked and activated in the tumor microenvironment. We aim to build a commercial enterprise to maximize our impact on the treatment of cancer. By pioneering a novel class of localized biologic drug candidates, powered by our PROBODY ® therapeutic technology platform, we are a leader in the field of masked, conditionally activated oncology therapeutics and have established biologics localization as a strategic area of research and development in the biopharmaceutical industry. Our vision is to transform lives with safer, more effective therapies with the goal to address major unmet needs in oncology. Our proprietary, versatile, multi-modality PROBODY technology platform is designed to enable conditional activation of potent masked biologic therapeutic candidates within the tumor microenvironment while minimizing drug activity in healthy tissues and circulation. Our platform is built on a strong foundation of tumor biology expertise, including deep knowledge of tumor-associated enzymes known as proteases. Proteases are tightly controlled in normal tissues but often dysregulated and active in tumor microenvironments where they play important roles in cancer cell migration, invasion and metastasis. Leveraging our deep scientific knowledge, we conceived of and constructed our PROBODY therapeutic platform which allows us to genetically engineer biologic therapeutic candidates to contain protease-cleavable masks. Our masking strategy is designed to reduce binding of biologic therapeutics to their targets until the mask is removed by proteases in the tumor microenvironment, providing more selective targeting of the tumor. We are employing our leading, masking platform technology to address some of the biggest challenges in oncology biologics research and development. These include the validation of potential new targets for antibody-drug conjugates (“ADCs”), increasing the therapeutic index for immune modulators such as cytokines, and opening therapeutic window for novel T-cell engagers (“TCEs”) targeting solid tumors. We have utilized our PROBODY therapeutic platform and masking technology to build a promising pipeline of potential first-in-class and best-in-class clinical-stage molecules. These are CX-2051, an investigational, conditionally activated ADC targeting epithelial cell adhesion molecule (“EpCAM”), and CX-801, an investigational, masked version of interferon alpha-2b (“IFNα2b”). Our current clinical-stage molecules address targets or mechanisms that have been previously validated as having anti-cancer activity but have been limited in their utilization due to toxicities in healthy tissues. We have incorporated our significant, multi-modality masking, conditional activation expertise and clinical learnings to optimize predicted therapeutic index and the clinical potential of these promising agents through tumor localized, conditional activation. CX-2051, a conditionally activated, PROBODY ADC, targets EpCAM. High expression of EpCAM has been documented in many tumor types, including colorectal cancer (“CRC”). The CX-2051 payload, a topoisomerase-1 inhibitor payload licensed from AbbVie (formerly ImmunoGen), is tailored to have anti-tumor activity against multiple EpCAM-expressing indications, including colorectal cancer. The payload-antibody linker we selected for CX-2051 is designed to drive bystander killing of neighboring tumor cells, contributing to anti-tumor activity. The design of CX-2051 is intended to establish a clinically meaningful therapeutic window for the systemic treatment of EpCAM-expressing cancers where previous industry efforts targeting EpCAM have not been successful due to dose-limiting toxicities. CX-2051 has demonstrated strong preclinical activity and tolerability in multiple preclinical models and encouraging initial Phase 1 data in late-line colorectal cancer. The IND for CX-2051 was allowed to proceed by the FDA in January 2024 and a Phase 1 clinical trial of CX-2051 in patients with EpCAM expressing solid tumors, with an initial focus in CRC, was commenced in April 2024. No pre-screening of CRC patients based on tumor EpCAM expression has been conducted because of anticipated high and uniform EpCAM expression in CRC. As of May 2025, the Phase 1 study had reached the seventh dose escalation level. In May 2025, the Company announced positive interim Phase 1 data as of an April 7, 2025 data cutoff in advanced metastatic colorectal cancer. The data encompassed results from 25 CRC patients treated with CX-2051 at 5 dose levels ranging from 2.4 mg/kg to 10 mg/kg, administered every three weeks (“Q3W”). The 2.4 mg/kg and 4.8 mg/kg doses were single patient dose escalation cohorts not anticipated to 22 be therapeutically active. At the 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg doses, 23 patients were treated, 18 of whom were efficacy evaluable, having had at least one post-baseline tumor assessment as of the data cutoff. Patients enrolled in the study at the time of data cutoff had previously received a median of 4 prior lines of therapy and all patients had previously been treated with irinotecan. 64% of patients had liver metastases, 64% had KRAS mutations, and 96% were microsatellite stable. Patients were not preselected based on EpCAM expression levels. As of the data cutoff, 18 patients were efficacy-evaluable at doses of 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg Q3W. Five of eighteen (28%) patients demonstrated confirmed partial responses per RECIST v1.1. Three of seven (43%) efficacy evaluable patients at the dose of 10 mg/kg Q3W demonstrated confirmed partial responses per RECIST v1.1. Seventeen of eighteen patients (94%) had disease control, defined as having an objective response or stable disease. Preliminary median progression free survival (PFS) was 5.8 months as of the data cutoff with 10 of 18 patients remaining on study treatment. As of the data cutoff, 25 patients were evaluable for safety. CX-2051 was generally well-tolerated as of the data cutoff with manageable adverse events, with no dose limiting toxicities. Most treatment related adverse events (TRAEs) were Grade 1 or Grade 2 in severity. The most common reported TRAEs were diarrhea (18 patients, 5 Grade 3), nausea (11 patients, 1 Grade 3), vomiting (8 patients, No Grade 3), fatigue (8 patients, 1 Grade 3), anemia (5 patients, 3 Grade 3), hypokalemia (3 patients, 1 Grade 3), neutrophil count decrease (2 patients, 2 Grade 3) and neutropenia (2 patients, 1 Grade 3). TRAEs included serious adverse events (SAEs) in 5 patients (1 Grade 2, 4 Grade 3). The SAEs included Grade 3 Diarrhea (1 patient), Grade 3 Anemia (1 patient), Grade 3 colitis (1 patient), Grade 3 Diarrhea and Acute kidney injury (1 patient) and Grade 2 Asthenia (1 patient). No Grade 4 or 5 TRAEs were observed as of the April 7, 2025 data cutoff. No events of interstitial lung disease or febrile neutropenia were reported as of the data cutoff. On August 13, 2025, the Company announced that a single Grade 5 treatment-related acute kidney injury occurred in a patient with a complex medical history including having a solitary kidney. The Grade 5 event was believed to be secondary to nausea, vomiting and diarrhea. The Company reported the event to the FDA in accordance with regulatory requirements. The CTMX-2051-101 Safety Review Committee reviewed the event and supported continued study execution and enrollment which are ongoing. Based on the positive interim Phase 1 dose escalation data in May 2025, dose expansions were initiated at the dose levels of 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg, administered every three weeks (Q3W) and are currently ongoing. In the third quarter of 2025, dose expansion enrollment continued with the goal of supporting a potential registrational study of CX-2051 monotherapy in advanced CRC. CX-2051 Phase 1 study enrollment is projected to reach approximately 100 patients by the first quarter of 2026. A CX-2051 Phase 1 data update is expected to be provided in the first quarter of 2026. Additionally, the Company expects to initiate enrollment of a Phase 1b study of CX-2051 in combination with bevacizumab in the first quarter of 2026, data from which is intended to inform potential CX-2051 late phase development in earlier lines of CRC therapy. The Company also continues to evaluate additional non-CRC, EpCAM expressing indications for potential CX-2051 development. CX-801 is our PROBODY interferon ("IFN") alpha( a )-2b clinical program. IFNα2b provides a potentially superior approach to activating anti-tumor immune responses. CX-801 is a dually masked, conditionally activated version of IFNα2b that has the potential to become a cornerstone of combination therapy for a wide range of tumor types. The IND for CX-801 was allowed to proceed by the FDA in January 2024, and in the third quarter of 2024 the first patient was dosed in the CX-801 Phase 1 dose escalation study in solid tumors. The Phase 1 dose escalation study is focused on patients with advanced melanoma. In Phase 1 dose escalation, the study will evaluate safety, translational biomarkers and signs of clinical activity for CX-801 monotherapy and in combination with KEYTRUDA ® . In the second quarter of 2024, CytomX announced a clinical collaboration with Merck to supply KEYTRUDA for evaluation of its combination with CX-801 in the Phase 1 study. The Phase 1 study is currently in the fourth monotherapy dose escalation cohort. In May 2025, Phase 1 dose escalation enrollment of CX-801 in combination with KEYTRUDA® (pembrolizumab) in advanced melanoma was initiated. Phase 1 CX-801 monotherapy biomarker data in melanoma patients will be presented at the Society of Immunotherapy of Cancer (SITC) 2025 Annual Meeting on November 8, 2025. The data to be presented indicate that CX-801 has been generally well tolerated to date and consistently increased expression of interferon-stimulated genes in paired tumor biopsies, suggesting preferential activity in tumors. Upregulation of immune checkpoint genes, including PD-1 and PD-L1, and activation of immune cell populations was also observed, providing a rationale for evaluating the combination of CX-801 and pembrolizumab. PK analysis also demonstrated dose-proportional exposure of CX-801, which remained predominantly in its intact (masked) form in circulation. Phase 1 clinical data from the CX-801 and KEYTRUDA® combination dose escalation portion of the study are expected in 2026. In addition to PROBODY ADCs like CX-2051 and PROBODY cytokines like CX-801, we view the field of masked biologics as having broad potential applicability across a range of therapeutic modalities, reflecting the versatility of our platform technology. A key focus of our current work with collaboration partners is T-cell engaging bispecific therapies (“TCEs”) where we have significant ongoing efforts with partners such as Regeneron and Astellas and maintain significant research expertise. For example, at SITC 2025, we presented preclinical data for CX-908, a dually masked PROBODY T-cell Engager targeting CDH3 and CD3. CX-908 potently induced tumor regressions in 23 established breast and lung cancer xenograft tumor models and demonstrated a 100-fold improvement in tolerability, including significantly reduced cytokine release vs. an unmasked CDH3xCD3 molecule. We view masking as a key strategy to widen a therapeutic window for T-cell engagers and view strategic partnering in this area as an important way to extend the reach of the PROBODY platform. We do not have any products approved for sale, and we continue to incur significant research and development as well as general and administrative expenses related to our operations. Global health authorities, including the FDA, regulate many aspects of a product candidate’s life cycle, including research and development and preclinical and clinical testing. We will need to commit significant time, resources, and funding to develop our wholly-owned and partnered product candidates in clinical trials. We are unable to provide the nature, timing, and estimated costs of the efforts necessary to complete the development of our product candidates because, among other reasons, of regulatory uncertainty, manufacturing limitations, and the pace of enrollment of our clinical trials, which is a function of many factors, including the availability and proximity of patients with the relevant condition. We currently have no manufacturing capabilities and do not intend to establish any such capabilities in the near term. As such, we are dependent on third parties to supply our product candidates according to our specifications, in sufficient quantities, on time, in compliance with appropriate regulatory standards and at competitive prices. Restructuring On January 6, 2025, we announced a restructuring plan (the “2025 Restructuring Plan”) to streamline our organization and prioritize CX-2051, CX-801 and our activities to support our research collaborations. The restructuring plan resulted in a reduction of approximately 40% of our workforce and was substantially completed in the first quarter of 2025. We recorded total restructuring charges of approximately $2.8 million, primarily related to one-time severance payments and other employee-related costs. This includes $1.7 million of research and development expenses and $1.1 million of general and administrative expenses that were recorded during the nine months ended September 30, 2025. Critical Accounting Policies and Estimates The preparation of our Condensed Financial Statements requires us to make estimates and judgments that affect the reported amounts in the financial statements and related disclosures. On an ongoing basis, management evaluates its significant accounting policies and estimates. We base our estimates on historical experience and on various market-specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ significantly from these estimates. Estimates are assessed each period and updated to reflect current information. A summary of our critical accounting policies and estimates is presented in Part II, Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2024. There have been no material changes to our critical accounting policies and estimates for the three months ended September 30, 2025. Components of Results of Operations Revenue Our revenue to date has been primarily derived from non-refundable license payments, milestone payments and reimbursements for research and development expenses under our research, collaboration, and license agreements. We recognize revenue from upfront payments over the term of our estimated period of performance under the agreement using an input method for the entire performance obligation. In applying the input method of revenue recognition, we use actual full-time equivalent (“FTE”) hours incurred relative to estimated total FTE hours expected to be incurred for each combined performance obligation over the estimated research service period of each collaboration target. In addition to receiving upfront payments, we are entitled to variable payments related to research and development services provided and may be entitled to milestone and other contingent payments upon achieving predefined objectives. Revenue from variable payments related to research and development or milestones and other contingent payments, when it is probable that there will not be a significant revenue reversal, is also recognized over the performance period based on a similar method. For the foreseeable future, we do not expect to generate any revenue from the sale of products unless and until such time as our product candidates have advanced through clinical development and obtained regulatory approval. We expect that any revenue we generate in the foreseeable future will fluctuate from year to year as a result of the timing and amount of milestones and other payments from our collaboration agreements with Amgen, Astellas, Bristol Myers Squibb, Regeneron, Moderna and any other collaboration partners, and as a result of the fluctuations in the research and development expenses we incur in the performance of assigned activities under these agreements. 24 Research and Development Expenses Our research and development expenses consist primarily of costs incurred to conduct research, such as the discovery and development of our product candidates, clinical development, including activities with third parties, such as contract research organizations (“CRO”) and contract development and manufacturing organizations (“CMO”), and the manufacture of drug products used in clinical trials, as well as the development of product candidates pursuant to our research, collaboration and license agreements. Research and development expenses include personnel costs, including stock-based compensation expense, contractor services, laboratory materials and supplies, depreciation and maintenance of research equipment, and an allocation of related facilities costs. We expense research and development costs as incurred. We expect our research and development expenses could vary substantially in the future as we prioritize our pipeline opportunities, advance our product candidates through clinical trials, initiate additional clinical trials, and pursue regulatory approval of our product candidates. The process of conducting the necessary clinical research to obtain regulatory approval is costly and time-consuming. The actual probability of success for our product candidates may be affected by a variety of factors including: the safety and efficacy of our product candidates, early clinical data, investment in our clinical program, the ability of collaborators to successfully develop our licensed product candidates, competition, manufacturing capability and commercial viability. We may never succeed in achieving regulatory approval for any of our product candidates. As a result of the uncertainties discussed above, we are unable to determine the duration and completion costs of our research and development projects or when and to what extent we will generate revenue from the commercialization and sale of our product candidates. General and Administrative Expenses General and administrative expenses include personnel costs, expenses for outside professional services and other allocated expenses. Personnel costs consist of salaries, bonuses, benefits and stock-based compensation. Outside professional services consist of accounting and audit services, legal and other consulting fees. Allocated expenses primarily consist of rent expense related to our office and information technology related costs. Interest Income Interest income primarily consists of interest income from our cash equivalents and investments, and accretion of discounts or amortization of premiums on our investments. Other Income (Expense), Net Other income (expense), net consists primarily of gains and losses resulting from changes to currency exchange rates. Income Taxes Income taxes are recorded in accordance with ASC 740, Accounting for Income Taxes, or ASC 740, which provides for deferred taxes using an asset and liability approach. We recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in our financial statements or tax returns. We determine our deferred tax assets and liabilities based on differences between the financial reporting and tax bases of assets and liabilities, which are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. Valuation allowances are provided, if based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. We also account for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, we recognize the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. 25 Results of Operations Revenue The following table summarizes our revenue by collaboration partner during the respective periods: Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 Change 2025 2024 Change (in thousands) (in thousands) Amgen $ — $ (783 ) $ 783 $ 9,818 $ 1,491 $ 8,327 Astellas 4,360 2,553 1,807 18,453 23,497 (5,044 ) Bristol Myers Squibb — 22,977 (22,977 ) 41,928 56,042 (14,114 ) Regeneron 1,600 2,896 (1,296 ) 5,307 7,925 (2,618 ) Moderna 3 5,789 (5,786 ) 32 11,055 (11,023 ) Total revenue $ 5,963 $ 33,432 $ (27,469 ) $ 75,538 $ 100,010 $ (24,472 ) The decrease in revenue of $27.5 million for the three months ended September 30, 2025, compared to the corresponding period of 2024 was primarily due to: • No revenue recognized under the BMS Agreement due to the completion of our performance obligations in the second quarter of 2025. BMS is responsible for the future research and development of the ongoing collaboration programs; • No revenue recognized under the Amgen Agreement as a result of Amgen terminating its license to the EGFR Product effective May 2025; • A decrease in revenue under the Regeneron Agreement driven by a primary focus on the most developed preclinical program in 2025; and • A decrease in revenue under the Moderna Agreement driven by Moderna's budget considerations in 2025 where the $9.3 million of remaining deferred revenue is expected to be recognized primarily in 2026 and 2027; partially offset by • An increase in revenue under the Astellas Agreement driven by continued progress of ongoing collaboration programs. The decrease in revenue of $24.5 million for the nine months ended September 30, 2025, compared to the corresponding period of 2024 was primarily due to: • A decrease in revenue under the BMS Agreement driven by the completion of our performance obligations in the second quarter of 2025. BMS is responsible for the future research and development of the ongoing collaboration programs; • A decrease in revenue under the Astellas Agreement primarily driven by higher preclinical milestone payments in the first quarter of 2024; • A decrease in revenue under the Regeneron Agreement driven by a primary focus on the most developed preclinical program in 2025; • A decrease in revenue under the Moderna Agreement driven by Moderna's budget considerations in 2025 where the $9.3 million of remaining deferred revenue is expected to be recognized primarily in 2026 and 2027; partially offset by • An increase in revenue under the Amgen Agreement due to a cumulative adjustment from a change in estimate of $8.4 million resulting from Amgen terminating its license to the EGFR Product in March 2025, effective May 2025. The remaining deferred revenue was recognized upon completion of our performance obligations in the second quarter of 2025. 26 Operating Costs and Expenses Research and Development Expenses The following table summarizes our research and development expenses by program incurred during the respective periods presented: Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 Change 2025 2024 Change (in thousands) (in thousands) External costs incurred by product candidate (target): CX-904 (EGFRxCD3) $ 150 $ 2,659 $ (2,509 ) $ 710 $ 5,847 $ (5,137 ) CX-2051 (EpCAM) 5,354 6,353 (999 ) 13,304 14,105 (801 ) CX-801 (IFNα2b) 369 456 (87 ) 1,308 2,060 (752 ) Other programs 462 783 (321 ) 1,357 5,596 (4,239 ) General research and development expenses 1,700 2,529 (829 ) 5,750 13,888 (8,138 ) Total external costs 8,035 12,780 (4,745 ) 22,429 41,496 (19,067 ) Internal costs 7,269 8,588 (1,319 ) 25,064 27,096 (2,032 ) Total research and development expenses $ 15,304 $ 21,368 $ (6,064 ) $ 47,493 $ 68,592 $ (21,099 ) Research and development expenses decreased by $6.1 million for the three months ended September 30, 2025, compared to the corresponding period of 2024 primarily due to: • a reduction in CX-904 spend due to program deprioritization in 2025; • lower CX-2051 manufacturing expenses partially offset by increased clinical spend; and • reduced general research and development expenses after the restructuring announced in January 2025. Research and development expenses decreased by $21.1 million for the nine months ended September 30, 2025, compared to the corresponding period of 2024 primarily due to: • a reduction in CX-904 spend due to program deprioritization in 2025; • lower CX-2051 manufacturing expenses partially offset by increased clinical spend; • reduced general research and development expenses as a result of the January 2025 restructuring; • lower spend on preclinical programs; and • a one-time royalty milestone payment of $5.0 million to ImmunoGen in 2024; partially offset by • a one-time restructuring expenses of $1.7 million which were primarily included in internal costs. General and Administrative Expenses Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 Change 2025 2024 Change (in thousands) (in thousands) General and administrative $ 6,427 $ 7,953 $ (1,526 ) $ 22,477 $ 24,102 $ (1,625 ) General and administrative expenses decreased by $1.5 million for the three months ended September 30, 2025, compared to the corresponding period of 2024, primarily driven by personnel related expenses as well as patent and legal expenses. General and administrative expenses decreased by $1.6 million for the nine months ended September 30, 2025, compared to the corresponding period of 2024, primarily driven by personnel related expenses and legal and consulting related expenses, partially offset by $1.1 million of one-time restructuring expenses. 27 Restructuring During the three and nine months ended September 30, 2025, we recognized aggregate restructuring cost (adjustment) of approximately ($0.1) million and $2.8 million, respectively, primarily related to severance and benefits. This included $1.7 million in research and development expenses and $1.1 million in general and administrative expenses. The total restructuring cost is expected to be approximately $2.8 million. The restructuring was substantially completed in the first quarter of 2025. Interest Income and Other Income (Expense), Net Three Months Ended Nine Months Ended September 30, September 30, 2025 2024 Change 2025 2024 Change (in thousands) (in thousands) Interest income $ 1,592 $ 1,693 $ (101 ) $ 3,725 $ 5,858 $ (2,133 ) Other income (expense), net 5 (7 ) 12 33 (19 ) 52 Total interest income and other expense $ 1,597 $ 1,686 $ (89 ) $ 3,758 $ 5,839 $ (2,081 ) Interest income decreased by $0.1 million and $2.1 million during the three months and nine months ended September 30, 2025, respectively, compared to the corresponding period of 2024. The decrease was primarily driven by lower interest rates and the lower average cash and cash equivalents and short-term investments position. Income Taxes September 30, September 30, Three Months Ended Nine Months Ended 2025 2024 Change 2025 2024 Change (in thousands) (in thousands) Provision for income taxes $ 58 $ 61 $ (3 ) $ 184 $ 162 $ 22 The $0.1 million and $0.2 million of tax provision represented the interest accrued for the three and nine months ended September 30, 2025, respectively, related to the proposed assessment received from the state of California for the years 2017 and 2018. Liquidity and Capital Resources Sources of Liquidity As of September 30, 2025, we had cash, cash equivalents and short-term investments of $143.6 million and an accumulated deficit of $682.4 million, compared to cash, cash equivalents and short-term investments of $100.6 million and an accumulated deficit of $691.6 million as of December 31, 2024. To date, we have financed our operations primarily through sales of our common stock in conjunction with the IPO, subsequent stock offerings and through our at-the-market offering, sales of our convertible preferred securities prior to our IPO, payments received under our collaboration agreements and proceeds from private placements of our common stock, warrants and pre-funded warrants. In July 2023, we completed a private placement and issued pre-funded warrants to purchase an aggregate of 14,423,077 shares of common stock, accompanying Tranche 1 warrants to purchase up to 5,769,231 shares of common stock and accompanying Tranche 2 warrants to purchase up to 5,769,231 shares of common stock, at a combined price of $2.08 per share. We received gross proceeds of approximately $30.0 million. In March 2024, we achieved a clinical candidate milestone for a second collaboration target as well as the GLP toxicology studies milestone for the first collaboration target nominated in January 2023 under the Astellas Agreement; as a result, we collected the two milestone payments totaling $10.0 million in April 2024. In the first quarter of 2025, we achieved the GLP toxicology studies for the second collaboration target nominated in March 2024 under the Astellas Agreement; as a result, we collected the $5.0 million milestone payment in March 2025. On January 6, 2025, we announced the 2025 Restructuring Plan to streamline our organization and prioritize CX-2051 investment and activities to support our research collaborations. The restructuring plan resulted in a reduction to our workforce by approximately 40% and was substantially completed in the first quarter of 2025. In February 2020, we initiated an at-the-market offering program (“ATM”) pursuant to a sales agreement with Jefferies, LLC (as amended on March 4, 2022 and August 9, 2024, the "Sales Agreement"). In 2024, we sold 3,925,202 shares at a weighted average price of $1.82 per share under our ATM offering for net proceeds of approximately $6.9 million after deducting sales commissions and related issuance cost. In 28 October 2025, we sold $4.3 million shares at a weighted average price of $3.43 per share under our ATM offering for net proceeds of approximately $14.4 million after deducting sales commissions and related issuance cost. In May 2025, we completed an underwritten public offering of 76,923,076 shares of common stock at a price of $1.30 per share and received net proceeds of approximately $93.4 million, after deducting underwriting discounts and commissions of $6.0 million and offering expenses of $0.6 million. Based upon our current operating plan and liquidity requirements, we expect our existing capital resources will be sufficient to fund operations into the second quarter of 2027. However, if the anticipated operating results are not achieved in future periods, our planned expenditures may need to be reduced in order to extend the time period over which the then-available resources would be able to fund the operations. The amounts and timing of our actual expenditures depend on numerous factors, including the progress of our preclinical and clinical development efforts, the results of any clinical trials and other studies, our operating costs and expenditures and other factors described under the caption “Risk Factors” in this Quarterly Report on Form 10-Q. The cost and timing of developing our product candidates is highly uncertain and subject to substantial risks and changes. As such, we may alter our expenditures as a result of contingencies such as the failure of one or all of our product candidates currently in clinical development, the acceleration of one or all of our product candidates in clinical development, the initiating of clinical trials for additional product candidates, the identification of more promising product candidates in our research efforts or unexpected operating costs and expenditures. We will need to raise additional capital to fund our operation in the future. There can be no assurance, however, that such efforts will be successful; or if they are successful, that the terms and conditions of such financing will be favorable to us. Summary Statement of Cash Flows The following table summarizes our cash flows for the periods indicated: Nine Months Ended September 30, 2025 2024 (in thousands) Net cash used in operating activities $ (52,344 ) $ (66,323 ) Net cash (used in) provided by investing activities (45,325 ) 84,565 Net cash provided by financing activities 93,803 5,273 Net (decrease) increase in cash, cash equivalents and restricted cash $ (3,866 ) $ 23,515 Cash Flows from Operating Activities During the nine months ended September 30, 2025, cash used in operating activities was $52.3 million, which consisted of a net income of $9.1 million and non-cash charges of $7.5 million, adjusted by a net decrease of $68.9 million relating to the change of our net operating assets and liabilities. The non-cash charges primarily consisted of $4.8 million in stock-based compensation, $3.3 million in non-cash lease expense, $0.9 million in depreciation and amortization, partially offset by $1.5 million in accretion of discounts on investments. The change in our net operating assets and liabilities was primarily due to: • a net decrease of $66.1 million in deferred revenue resulting from the continued recognition of deferred revenue from existing customers; • a decrease of $3.9 million in accounts payable, accrued and other long-term liabilities primarily due to timing of payments; and • a decrease of $0.4 million in cashflows from prepaid and other current assets primarily due to increase in advance payments, partially offset by • an increase of $1.5 million in cashflows from accounts receivable primarily due to timing of collection of service revenue. During the nine months ended September 30, 2024, cash used in operating activities was $66.3 million, which consisted of a net income of $13.0 million and non-cash charges of $5.6 million, adjusted by a net decrease of $84.9 million relating to the change of our net operating assets and liabilities. The non-cash charges primarily consisted of $5.8 million in stock-based compensation, $3.0 million in non-cash lease expense, $1.3 million in depreciation and amortization, partially offset by $4.5 million in accretion of discounts on investments. The change in our net operating assets and liabilities was primarily due to: 29 • a net decrease of $82.7 million in deferred revenue resulting from the continued recognition of deferred revenue from existing customers; • a decrease of $4.1 million in accounts payable, accrued and other long-term liabilities primarily due to timing of payments; offset by • an increase of $1.9 million in cashflows from accounts receivable, prepaid and other current assets primarily due to decrease in advance payments. Cash Flows from Investing Activities During the nine months ended September 30, 2025, cash used in investing activities was $45.3 million consisted of $148.3 million used in purchase of short-term investment and purchase of property and equipment partially offset by $103.0 million of proceeds from the maturities of short-term investments. During the nine months ended September 30, 2024, cash provided by investing activities was $84.6 million, which consisted of $190.5 million of proceeds from the maturities of short-term investments partially offset by $105.7 million used in the purchase of short-term investments and $0.2 million of capital expenditures used to purchase property and equipment. Cash Flows from Financing Activities During the nine months ended September 30, 2025, cash provided by financing activities was $93.8 million, which consisted of $93.4 million of net proceeds from issuance of common stock, net of issuance costs, and $0.4 million of proceeds from the exercise of stock options and employee stock purchases under the employee stock purchase plan. During the nine months ended September 30, 2024, cash provided by financing activities was $5.3 million, which consisted of $4.8 million of net proceeds from issuance of common stock, net of issuance costs, and $0.4 million of proceeds from the exercise of stock options and employee stock purchases under the employee stock purchase plan. Contractual Obligations During the three months ended September 30, 2025, there were no material changes in contractual obligations from the amounts disclosed in our Annual Report on Form 10-K for the year ended December 31, 2024. 30 Item 3. Quantitative and Qualitat ive Disclosure About Market Risk We are a smaller reporting company as defined by Rule 12b-2 of the Exchange Act and are not required to provide the information required under this item. Item 4. Controls and Proc edures Evaluation of Disclosure Controls and Procedures The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act of 1934, as amended (the “Exchange Act”) refers to controls and other procedures of an issuer that are designed to ensure that information required to be disclosed by the issuer in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by an issuer in the reports that it files or submits under the Exchange Act is accumulated and communicated to the issuer’s management, including its Principal Executive and Principal Financial Officers, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure. In designing and evaluating the disclosure controls and procedures, our management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and our management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Our disclosure controls and procedures are designed to provide reasonable assurance of achieving their control objectives. Our management, with the participation of our Principal Executive and Principal Financial Officers, has evaluated the effectiveness of our disclosure controls and procedures as of September 30, 2025, the end of the period covered by this Quarterly Report on Form 10-Q. Based on their evaluation and subject to the foregoing, the Principal Executive and Principal Financial Officers concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of September 30, 2025. Changes in Internal Controls Over Financial Reporting There was no change in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that occurred during our fiscal quarter ended September 30, 2025 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting. 31 PART II – OTHER INFORMATION