CytomX Therapeutics, Inc. 10-K

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations The following discussion should be read in conjunction with the attached financial statements and notes thereto. This Annual Report on Form 10-K, including the following sections, contains forward-looking statements within the meaning of the federal securities laws. These statements are subject to risks and uncertainties that could cause actual results and events to differ materially from those expressed or implied by such forward-looking statements. For a detailed discussion of these risks and uncertainties, see the “Risk Factors” section in Item 1A of this Annual Report on Form 10-K. We caution the reader not to place undue reliance on these forward-looking statements, which reflect management’s analysis only as of the date of this Form 10-K. We undertake no obligation to update forward-looking statements, which reflect events or circumstances occurring after the date of this Form 10-K. For a discussion related to the results of operations for 2022 compared to 2021, refer to Part II, Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations - Comparison of Years Ended December 31, 2022 and 2021" in our Annual Report on Form 10-K for the year ended December 31, 2022 filed with the SEC on March 27, 2023. Overview We are a clinical-stage, oncology-focused biopharmaceutical company focused on developing novel, conditionally activated biologics designed to be localized to 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 lead the field of conditionally activated oncology therapeutics and have established biologics localization as a strategic area of research and development. 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 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, conditional activation 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”), opening therapeutic window for novel T-cell engagers (“TCEs”) targeting solid tumors, and increasing the therapeutic index for immune modulators such as cytokines. We are also exploring the potential for our PROBODY platform in preclinical research in areas outside of oncology, including in our collaboration with Moderna. We have utilized our PROBODY therapeutic platform to build a promising, broad pipeline of potential first-in-class and best-in-class clinical-stage molecules. These are CX-904, a conditionally activated, PROBODY® TCE, targeting the epidermal growth factor receptor (“EGFR”) on tumor cells and the CD3 receptor on T cells; 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 systemic toxicities. We have incorporated our significant platform expertise and clinical learnings to optimize predicted therapeutic index and the clinical potential of these promising agents through tumor localized conditional activation. Reinforcing our leadership in the field of conditional activation, in 2022 we advanced our first TCE into the clinic. CX-904, partnered with Amgen, is a conditionally activated TCE against EGFR and CD3. In preclinical studies, CytomX’s PROBODY EGFRxCD3 TCE demonstrated anti-tumor activity and better tolerability when compared to TCEs without PROBODY masking. In May 2022, the first patient was dosed in a Phase 1 study evaluating CX-904 as a treatment for patients with advanced solid tumors. Patient enrollment in the Phase 1 dose escalation portion of the study continues to progress. We reported in January 2023 that the initial single patient cohort phase of the study was complete and that the “3+3” patient cohort phase had been initiated. Backfilling of certain dose escalation cohorts has also been initiated and dose ranging continues. Initial Phase 1a data in EGFR positive solid tumors is expected in the second half of 2024. A decision to potentially expand into Phase 1b is also anticipated in 2024, which will be taken in conjunction with our partner, Amgen. Our pipeline also includes CX-2051, a wholly-owned conditionally activated, PROBODY ADC paired with a next-generation camptothecin payload and directed toward the epithelial cellular adhesion molecule (EpCAM). CX-2051 is licensed from 76 ImmunoGen. CX-2051 has been tailored to optimize the therapeutic index for the systemic treatment of EpCAM-expressing epithelial cancers where previous industry efforts targeting EpCAM have not been successful due to dose-limiting toxicities. CX-2051 has demonstrated a wide predicted therapeutic index and strong preclinical activity and tolerability in multiple preclinical models, including colorectal cancer. The IND for CX-2051 was cleared by the FDA in January 2024 and we expect Phase 1 clinical initiation in EpCAM expressing solid tumors, including CRC in the first half of 2024. The Phase 1 dose escalation design will follow a Bayesian Optimal Interval (BOIN) design and intended to demonstrate rapid clinical proof of concept and potentially move into dose expansion studies in 2025. Another wholly-owned emerging product candidate is CX-801, an interferon ("IFN") alpha-2b PROBODY. IFNα2b provides a potentially superior approach to activating anti-tumor immune responses than other cytokines. 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 cleared by the FDA in January 2024 and initiation of Phase 1 dose escalation in solid tumors including melanoma, renal, and head and neck squamous cell carcinoma is expected in the first half of 2024. In Phase 1 dose escalation, we will use a BOIN design to evaluate safety and signs of clinical activity for CX-801 and progress into combinations, where CX-801 has the potential to be cornerstone of therapy, including in combination with checkpoint inhibitors. CX-2029 was previously developed in a global co-development collaboration with AbbVie. This program is intended to open a therapeutic window for successful targeting of CD71, also known as the transferrin receptor 1 (“TfR1”). CD71 is a cell surface protein essential for iron uptake in dividing cells and is highly expressed in a number of solid and hematologic cancers. However, given its central role in iron metabolism, CD71 is present on most healthy cells and is thought to be an undruggable target with conventional ADCs. CX-2029 is conjugated with the tubulin inhibitor, monomethyl auristatin E (“MMAE”), as the payload. In March 2023, following the completion of the Phase 2 Study in squamous non-small cell lung cancer (“sqNSCLC”), head and neck squamous cell carcinoma (“HNSCC”), esophageal and gastro-esophageal junction (“E/GEJ”) cancers, AbbVie notified CytomX that it would not advance CX-2029 into additional clinical studies and terminated the 2016 CD71 License and Collaboration Agreement. CytomX re-acquired full rights to CX-2029 but does not currently have plans to make further significant investments in the solid tumor program in the near-term but continues to view CD71 as a target of strategic interest, including novel next-generation strategies. Praluzatamab ravtansine is our conditionally activated ADC directed toward CD166 which was previously evaluated in a three-arm Phase 2 study in patients with advanced human epidermal growth factor receptor 2 (“HER2”)-non-amplified breast cancer. Arms A and B examined praluzatamab ravtansine monotherapy in patients with hormone receptor-positive/HER2-non-amplified breast cancer and TNBC, respectively. Arm C studied praluzatamab ravtansine in combination with pacmilimab (CX-072), our wholly-owned PD-L1 inhibitor, in patients with TNBC. In July 2022, the Company disclosed topline data demonstrating praluzatamab ravtansine met the primary efficacy endpoint of confirmed objective response rate greater than 10 percent in hormone receptor-positive/HER2-non-amplified breast cancer. The confirmed objective response was 15% and demonstrated median progression-free survival of 2.6 months. Ocular and neuropathic toxicities were the most common treatment-related adverse events. Based on these data, the Company announced it would deprioritize further investment in praluzatamab ravtansine. The final Phase 2 study data in advanced breast cancer were presented at the San Antonio Breast Cancer Symposium in 2022. We are also continuously engaged in drug discovery efforts towards the generation of new clinical candidates across multiple modalities for the treatment of cancer, including additional ADCs, Cytokines, TCEs, and mRNAs reflecting the versatility of our PROBODY platform. We currently have more than 15 active drug discovery and/or development programs. We do not have any products approved for sale, and we continue to incur significant research and development and general administrative expenses related to our operations. As of December 31, 2023 and December 31, 2022, we had an accumulated deficit of $723.4 million and $722.9 million, respectively. 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. 77 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 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. AbbVie, one of our previous collaboration partners, entered into a license agreement with Seagen Inc. (“SGEN”) to license certain intellectual property rights. As part of the collaboration agreement with AbbVie, we received a sublicense to these intellectual property rights and therefore paid SGEN sublicense fees. These sublicense fees were treated as reductions to the transaction price and combined with the performance obligation to which they relate. Milestone payments, when considered probable of being reached and when a significant revenue reversal would not be probable of occurring, are also recorded net of the associated sublicense fees and included in the transaction price. 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. 78 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. The state of California contested our tax position on revenue apportionment for upfront and milestone payments resulting from our collaboration and licensing agreements for the years 2017 and 2018. We received a proposed assessment in September 2023 and filed a protest to contest the proposed assessment in November 2023. We recorded an uncertain tax position of $3.9 million in long term liabilities for the proposed tax assessment, penalties and interest through December 31, 2023. On August 16, 2022, the Inflation Reduction Act of 2022 (“IRA”) was signed into law. Among other changes to the Internal Revenue Code, the IRA imposes a 15% corporate alternative minimum tax on certain corporations and 1% excise tax on public company stock buybacks for tax years beginning after December 31, 2022. The Company does not expect these provisions to have a material impact. Comparison of Years Ended December 31, 2023 and 2022 Revenue The following table summarizes our revenue by collaboration partner during the respective periods: Year Ended December 31, 2023 2022 Change (in thousands) AbbVie $ 3,688 $ 18,563 $ (14,875 ) Amgen 5,739 4,967 772 Astellas 24,453 20,491 3,962 Bristol Myers Squibb 49,300 9,142 40,158 Regeneron 7,194 — 7,194 Moderna 10,840 — 10,840 Total Revenue $ 101,214 $ 53,163 $ 48,051 The increase in revenue of $48.1 million for 2023 compared to 2022 was primarily due to: • An increase in revenue under the BMS Agreement driven by higher percentage of completion of the existing and new targets selected in 2022; • An increase in revenue under the Regeneron Agreement and Moderna Agreement due to new preclinical studies that commenced during the current year; • An increase in revenue under the Astellas Agreement primarily driven by a $5.0 million clinical candidate milestone achieved in January 2023; • An increase in revenue under the Amgen Agreement driven by higher percentage of completion the CX-904 development in the current year primarily due to an increase in projected hours-to-completion in prior year; • A decrease in revenue under the AbbVie Agreement due to termination of the agreement in March 2023. 79 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: Year Ended December 31, 2023 2022 Change External costs incurred by product candidate (target): (in thousands) CX-904 (EGFRxCD3) $ 2,790 $ 2,822 $ (32 ) Praluzatamab ravtansine, CX-2009 (CD166) 2,671 15,809 (13,138 ) CX-2029 (CD71) 2,608 9,708 (7,100 ) Pacmilimab, CX-072 (PD-L1) (120 ) 948 (1,068 ) Other wholly owned and partnered programs 25,525 14,024 11,501 General research and development expenses 9,906 13,338 (3,432 ) Total external costs 43,380 56,649 (13,269 ) Internal costs 34,300 55,000 (20,700 ) Total research and development expenses $ 77,680 $ 111,649 $ (33,969 ) Research and development expenses decreased by $34.0 million for 2023, compared to 2022 primarily driven by a decrease in personnel related expenses as a result of the workforce reduction in 2022, as well as winding down of laboratory contract services and clinical study activities related to the CX-2009 and CX-2029 programs, partially offset by an increase in laboratory contract services related to IND enabling activities for CX-2051 and CX-801 programs. General and Administrative Expenses Year Ended December 31, 2023 2022 Change (in thousands) General and administrative $ 30,018 $ 42,849 $ (12,831 ) General and administrative expenses decreased by $12.8 million for 2023, compared to 2022 primarily driven by a decrease in personnel related expenses as a result of the workforce reduction in 2022, reduced external vendor services, and lower building rent as a result of a partial sublease of the Company’s headquarters. Interest Income and Other Income (Expense), Net Year Ended December 31, 2023 2022 Change (in thousands) Interest income $ 9,837 $ 1,678 $ 8,159 Other income (expense), net (30 ) 340 (370 ) Total interest income and other expense $ 9,807 $ 2,018 $ 7,789 Interest Income Interest income increased by $8.2 million during 2023 compared to 2022, primarily driven by higher interest rates in 2023. Income Taxes Year Ended December 31, 2023 2022 Change (in thousands) Provision for income taxes $ 3,892 $ — $ 3,892 The $3.9 million tax provision represented the uncertain tax position related to the proposed assessment received from the state of California for the years 2017 and 2018, including penalties and interest through December 31, 2023. 80 Liquidity and Capital Resources Sources of Liquidity As of December 31, 2023, we had cash, cash equivalents and short-term investments of $174.5 million and an accumulated deficit of $723.4 million, compared to cash, cash equivalents and investments of $193.7 million and an accumulated deficit of $722.9 million as of December 31, 2022. 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 November 2022, we entered into a Collaboration and License Agreement with Regeneron Pharmaceuticals, Inc. (the “Regeneron Agreement”) 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. Pursuant to the Regeneron Agreement, we collected an upfront fee of $30.0 million. In December 2022, we entered into a Collaboration and License Agreement with ModernaTX, Inc. (the “Moderna Agreement”) 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. Pursuant to the Moderna Agreement, we collected an upfront fee and prepaid research funding of $35.0 million in January 2023. 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. On July 13, 2022, we announced a restructuring plan to prioritize resources on our emerging pre-clinical and early clinical pipeline as well as our existing collaboration partnerships. The restructuring plan resulted in a reduction to our workforce by approximately 40%, and was substantially completed by the fourth quarter of 2022. We incurred aggregate restructuring charges of approximately $7.5 million, primarily related to one-time severance payments and other employee-related costs. Based upon our current operating plan, we expect our existing capital resources will be sufficient to fund operations into the second half of 2025. However, if the anticipated operating results and future financing 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 Annual Report on Form 10-K. 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 funds 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: Year Ended December 31, 2023 2022 (in thousands) Net cash used in operating activities $ (56,035 ) $ (110,788 ) Net cash (used in) provided by investing activities (150,674 ) 98,260 Net cash provided by financing activities 30,230 648 Net decrease in cash, cash equivalents and restricted cash $ (176,479 ) $ (11,880 ) Cash Flows from Operating Activities 2023 During the year ended December 31, 2023, cash used in operating activities was $56.0 million, which consisted of a net loss of $0.6 million and a net decrease of $62.4 million relating to the change of our net operating assets and liabilities, offset by non-cash charges of $7.0 million. The non-cash charges primarily consisted of $8.6 million in stock-based compensation, $3.7 million in non-cash lease expense and $2.1 million in depreciation and amortization, offset by $7.4 million in net accretion of discounts on our investments. 81 The change in our net operating assets and liabilities was primarily due to: • a net decrease of $89.0 million in deferred revenue resulting from the continued recognition of deferred revenue from existing and new customers; • a decrease of $8.5 million in accounts payable, accrued and other long-term liabilities primarily due to decrease of payroll-related expenses, restructuring related expenses, and laboratory contract services; offset by • an increase of $32.6 million in cash flows from accounts receivable primarily related to the receipt of the $35.0 million upfront payment and prepaid research under the Moderna agreement entered into in December 2022. • an increase of $2.5 million in cashflows from prepaid and other current assets primarily due to a decrease in advance payments to our third party manufacturing vendors and timing of payments. 2022 During the year ended December 31, 2022, cash used in operating activities was $110.8 million, which consisted of a net loss of $99.3 million and a net decrease of $30.7 million relating to the change of our net operating assets and liabilities, offset by non-cash charges of $19.2 million. The non-cash charges primarily consisted of $13.1 million in stock-based compensation, $3.4 million in non-cash lease expense and $2.7 million in depreciation, amortization, and impairment charges. The change in our net operating assets and liabilities was primarily due to: • an increase of $35.2 million in accounts receivable primarily related to the upfront payment and prepaid research under the Moderna Agreement entered into in December 2022; • a decrease of $9.8 million in accrued liabilities and accounts payable primarily due to timing of payments; • a decrease of $2.3 million in cash flows from prepaid expenses and other current assets and other assets primarily due to increase in advance payments to our third-party manufacturing vendors and timing of payments; • a net increase of $16.6 million in deferred revenue consisting of an increase of $69.6 million in deferred revenue related to new agreements with Regeneron and Moderna partially offset by a decrease of $53.0 million resulting from the continued recognition of deferred revenue from existing customers. Cash Flows from Investing Activities During year ended December 31, 2023, cash provided by investing activities was $150.7 million, which consisted of $424.8 million used in the purchase of short-term investments and $0.8 million of capital expenditures used to purchase property and equipment, partially offset by $275.0 million in proceeds received upon the maturity of marketable securities. During year ended December 31, 2022, cash provided by investing activities was $98.3 million, which consisted of $100.0 million in proceeds received upon the maturity of short-term marketable securities, partially offset by $1.7 million of capital expenditures used to purchase property and equipment. Cash Flows from Financing Activities During the year ended December 31, 2023, cash provided by financing activities consisted of $29.7 million of net proceeds from issuance of pre-funded warrants and warrants and $0.6 million of proceeds from the exercise of stock options and employee stock purchases under the employee stock purchase plan (“ESPP”). During the year ended December 31, 2022, cash provided by financing activities consisted of $0.6 million of proceeds from the exercise of stock options and employee stock purchases under the ESPP. 82 Contractual Obligations The following table summarizes our contractual obligations that become due within the next year (in thousands): Payments Due by 2024 Operating leases (1) $ 5,572 Royalty obligations (2) 150 License maintenance fees (3) 1,050 Milestone Payments (4) 5,456 Total contractual obligations $ 12,228 (1) We lease our current facility under a long-term operating lease, which expires in 2026. The lease provides us with one option to extend the lease term for a period of five years at the then fair market rental value. (2) We have royalty obligations under the terms of certain exclusive licensed patent rights. The royalty obligations are cancellable any time by giving notice to the licensor, with the termination being effective 60 days after giving notice. See Part II. Item 8. Financial Statements and Supplementary Data, Note 9 - “License Agreement" in the accompanying Notes to the financial statements for more information. Sublicense fees payable to UCSB for potential milestones that are probable to be earned by the Company in 2024 are not included. (3) We have annual license maintenance fees under the terms of certain license agreement with UCSB and SGEN. See Part II. Item 8. Financial Statements and Supplementary Data, Note 9 - “License Agreement” in the accompanying Notes to the financial statements for more information. (4) We have development milestone payments under the terms of certain license agreements. A development milestone is payable after dosing the first patient in a Phase 1 Clinical Study, which we expect to occur in 2024. We enter into agreements in the normal course of business with CROs for clinical trials and with vendors for pre-clinical studies and other services and products for operating purposes, which are cancelable at any time by us, generally upon 30 to 60 days prior written notice. These payments are not included in the above table of contractual obligations. The above table also excludes unrecognized tax benefits of $2.3 million as of December 31, 2023 related to uncertain tax position which would affect the Company’s effective tax rate if recognized. Segment Information We have one primary business activity and operate as one reportable segment. Critical Accounting Policies and Estimates Our management’s discussion and analysis of our financial condition and results of operations is based on our financial statements, which have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”). The preparation of these financial statements requires our management to make judgments and estimates that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported revenue generated and expenses incurred during the reporting periods. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these judgments and estimates under different assumptions or conditions and any such differences may be material. We believe that the accounting policies discussed below are critical to understanding our historical and future performance, as these policies relate to the more significant areas involving management’s judgments and estimates. Revenue Recognition We recognize revenue when our customer obtains control of the promised goods or services, in an amount that reflects the consideration which we have received or expect to receive in exchange for those goods or services. Our revenues are primarily derived through our license, research, development and commercialization agreements. The terms of these types of agreements may include (i) licenses for our technology or programs, (ii) research and development services, and (iii) services or obligations in connection with participation in research or steering committees. Payments to us under these arrangements typically include one or more of the following: nonrefundable upfront and license fees, research funding, milestone and other contingent payments to us for the achievement of defined collaboration objectives and certain preclinical, clinical, regulatory and sales-based events, as well as royalties on sales of any commercialized products. We assess whether the promises in our arrangements with 83 customers are considered as distinct performance obligations that should be accounted for separately. Judgment is required to determine whether the license to our intellectual property is distinct from the research and development services or participation on steering committees. Our collaboration and license agreements may include contingent payments related to specified research, development and regulatory milestones. Such milestone payments are typically payable under the collaborations when the collaboration partner claims or selects a target, or initiates or advances a covered product candidate in preclinical or clinical development, upon submission for marketing approval of a covered product with regulatory authorities; or upon receipt of actual marketing approvals of a covered product or for additional indications. To date, we have concluded that these contingent payments should be fully constrained until the conditions are met. At each reporting date, we re-evaluate whether the milestones are considered probable of being achieved and estimate the amount to be included in the transaction price by using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price in such period of determination. Our collaboration and license agreements may also include contingent payments related to sales-based milestones. Sales-based milestones are typically payable when annual sales of a covered product reach specified levels. Sales-based milestones are recognized at the later of when the associated performance obligation has been satisfied or when the sales occur. Unlike other contingency payments, such as regulatory milestones, sales-based milestones are not included in the transaction price based on estimates at the inception of the contract, but rather, are included when the sales or usage occur. As of December 31, 2023, no sales-based milestones have been recognized. The transaction price in each arrangement is allocated to the identified performance obligations based on the relative standalone selling price (“SSP”) of each distinct performance obligation, which requires judgment. In instances where SSP is not directly observable, such as when a license or service is not sold separately, SSP is determined using information that may include market conditions and other observable inputs. Due to the early stage of our licensed technology, the license of such technology is typically combined with research and development services and steering committee participation as one performance obligation. In the event that we receive non-cash consideration such as consideration in the form of a research license and research support services from the counterparty, the transaction price of a non-monetary exchange that has commercial substance is estimated based on the fair value of the non-cash consideration received, which may be determined through a valuation analysis. Most of our collaboration arrangements are related to delivering a combined performance obligation satisfied over time. Revenue is recognized over the estimated research period using an input measure based on our actual full-time employee ("FTE") hours incurred as a percentage of projected FTE hours for completing the performance obligation. We evaluate the measure of progress each reporting period and, if necessary, we adjust the measure of performance and related revenue recognition. There have been changes in estimates of research service periods and/or the related estimated FTE hours-to-completion of certain of our research development programs in each reporting period. For example, changes in our estimated research service period resulted in recognition of higher total revenue of $8.2 million for certain programs in aggregate and lower total revenue of $6.0 million for other programs in aggregate, in the fourth quarter of 2023, as compared to the estimates in place at the end of the third quarter of 2023. Such adjustments have impacted and will continue to impact the amounts and timing of our revenue recognized. Any consideration payable to our customers is treated as a reduction to the transaction price and revenue, unless the payment to the customer is in exchange for distinct good and services. Research and Development Expenses We record accrued liabilities for estimated costs of research, preclinical and clinical studies and contract manufacturing activities, which are a significant component of research and development expenses. A substantial portion of our ongoing research and development activities is conducted by third-party service providers, including CROs. Our contracts with CROs generally include pass-through costs, such as regulatory expenses, investigator fees, travel costs and other miscellaneous costs. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payments that do not match the periods over which materials or services are provided to us under such contracts. We accrue the costs incurred under agreements with these third parties based on actual work completed in accordance with the respective agreements. In the event we make advance payments, they are recorded as prepaid expenses and recognized as the services are performed. We determine the estimated costs through discussions with internal personnel and external service providers as to the progress of stage of completion of the services and the agreed-upon fees to be paid for such services. 84 We make significant judgments and estimates in determining the accrual balance in each reporting period. As actual costs become known, we adjust our accruals. Although we do not expect our estimates to be materially different than the actual amounts incurred, such estimates for the status and timing of services performed relative to the actual status and timing of services performed may vary and could result in us reporting amounts that are too high or too low in any one period. Our accrual is dependent, in part, upon the receipt of timely and accurate reporting from CROs and other third-party vendors. Variations in the assumptions used to estimate accruals including, but not limited to, the number of patients enrolled, the rate of patient enrollment and the actual services performed, may vary from our estimates, resulting in adjustments to clinical trial expenses in future periods. For example, during the three and nine months ended September 30, 2023, we recorded a $0.7 million credit upon final reconciliation of the CX-072 clinical trial and a $0.6 million credit in closing out certain activities of the CX-2009 clinical trial. Changes in these estimates that result in material changes to our accruals could materially affect our financial condition and results of operations. Uncertain Tax Position We file income taxes in the U.S. federal jurisdiction, the state of California and various other U.S. states. The state of California contested our tax position on revenue apportionment for upfront and milestone payments resulting from our collaboration and licensing agreements for the years 2017 and 2018. In September 2023, we received a Notice of Proposed Assessment (“NOPA”) from the Franchise Tax Board. We recorded an uncertain tax position of $3.9 million in long term liabilities for the proposed tax assessment, penalties and interest through December 31, 2023. Additional utilization of carryforward attributes and indirect federal tax effects of the assessment would result in a reduction in deferred tax assets of $5.1 million. We 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, we are unable to estimate a date by which this matter will be resolved. Item 7A. Quantitative and Qualitat ive Disclosures about Market Risk We are a smaller reporting company as defined by Rule 12b-2 of the Securities Exchange Act of 1934, or the Exchange Act, and are not required to provide the information under this item. 85 Item 8. Financial Stateme nts and Supplementary Data CYTOMX THERAPEUTICS, INC. ANNUAL REPORT ON FORM 10-K INDEX TO AUDITED FINANCIAL STATEMENTS Page Reports of Independent Registered Public Accounting Firm (PCAOB ID: 42 ) 87 Financial Statements Balance Sheets 89 Statements of Operations and Comprehensive Loss 90 Statements of Stockholders’ Deficit 91 Statements of Cash Flows 92 Notes to Financial Statements 93 86 Report of Independent Registered Public Accounting Firm To the Stockholders and the Board of Directors of CytomX Therapeutics, Inc. Opinion on the Financial Statements We have audited the accompanying balance sheets of CytomX Therapeutics, Inc. (the Company) as of December 31, 2023 and 2022, the related statements of operations and comprehensive loss, stockholders' deficit and cash flows for the years then ended, and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2023 and 2022, and the results of its operations and its cash flows for the years then ended, in conformity with U.S. generally accepted accounting principles. Basis for Opinion These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audit, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting. Accordingly, we express no such opinion. We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion. 87 Critical Audit Matter The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates. Accounting for revenue and collaboration agreements Description of the Matter The Company recorded revenue from collaboration agreements of $101.2 million for the year ended December 31, 2023. As described in Note 2 to the financial statements, the terms of the Company’s collaboration agreements may include licenses for the Company’s technology or programs, research and development services, and services or obligations in connection with participation in research or steering committees. Amounts received under these arrangements typically include nonrefundable upfront payments and license fees, research funding, milestone and other contingent payments for the achievement of defined collaboration objectives and certain preclinical, clinical, regulatory and sales-based events, as well as royalties on sales of any commercialized products. Auditing the Company’s accounting for revenue from collaboration agreements was complex and required significant judgments primarily in identifying which elements represent distinct performance obligations, determining the measurement and allocation of arrangement consideration, and evaluating estimates of the total expected inputs under the input method for revenue recognized over time. How We Addressed the Matter in Our Audit To test the accounting treatment for revenue from collaboration agreements, our audit procedures included, among others, whether the identified performance obligations were properly determined, and the transaction price was properly measured and allocated to the identified performance obligations. To test the measurement of efforts toward satisfying the performance obligation, our audit procedures included, among others, testing a sample of cash receipts, reviewing management’s analysis for accuracy and completeness by agreeing data to the underlying contract, inspecting research or steering committee minutes, testing the application of the input method for the recognition of revenue, including testing the estimated total inputs and actual inputs incurred. /s/ Ernst & Young LLP We have served as the Company’s auditor since 2017. San Jose, California March 11, 2024 88 CYTOMX THERAPEUTICS, INC. BALANCE SHEETS (in thousands, except share and per share data) December 31, December 31, 2023 2022 Assets Current assets: Cash and cash equivalents $ 17,171 $ 193,650 Short-term investments 157,338 — Accounts receivable 3,432 35,986 Prepaid expenses and other current assets 4,995 7,466 Total current assets 182,936 237,102 Property and equipment, net 3,958 5,072 Intangible assets, net 729 875 Goodwill 949 949 Restricted cash 917 917 Operating lease right-of-use asset 12,220 15,949 Other assets 83 27 Total assets $ 201,792 $ 260,891 Liabilities and Stockholders' Deficit Current liabilities: Accounts payable $ 1,458 $ 2,809 Accrued liabilities 17,599 24,450 Operating lease liabilities - short term 4,589 4,082 Deferred revenues, current portion 132,267 121,267 Total current liabilities 155,913 152,608 Deferred revenue, net of current portion 80,048 180,059 Operating lease liabilities - long term 9,385 13,975 Other long-term liabilities 3,893 — Total liabilities 249,239 346,642 Commitments and contingencies (Note 10) Stockholders' deficit Convertible preferred stock, $ 0.00001 par value; 10,000,000 shares authorized and no shares issued and outstanding — — Common stock, $ 0.00001 par value; 150,000,000 shares authorized, and 67,310,838 and 66,228,046 shares issued and outstanding at December 31, 2023 and 2022, respectively 1 1 Additional paid-in capital 675,905 637,117 Accumulated other comprehensive income 95 10 Accumulated deficit ( 723,448 ) ( 722,879 ) Total stockholders' deficit ( 47,447 ) ( 85,751 ) Total liabilities and stockholders' deficit $ 201,792 $ 260,891 See accompanying notes to financial statements 89 CYTOMX THERAPEUTICS, INC. STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (in thousands, except share and per share data) Year Ended December 31, 2023 2022 Revenues $ 101,214 $ 53,163 Operating expenses: Research and development 77,680 111,649 General and administrative 30,018 42,849 Total operating expenses 107,698 154,498 Loss from operations ( 6,484 ) ( 101,335 ) Interest income 9,837 1,678 Other income (expense), net ( 30 ) 340 Income (Loss) before income taxes 3,323 ( 99,317 ) Provision for income taxes 3,892 — Net loss ( 569 ) ( 99,317 ) Other comprehensive loss: Unrealized gain on available-for-sale investments, net of tax 85 252 Total comprehensive loss $ ( 484 ) $ ( 99,065 ) Net loss per share, basic and diluted $ ( 0.01 ) $ ( 1.51 ) Shares used to compute net loss per share, basic and diluted 73,808,237 65,739,844 See accompanying notes to financial statements 90 CYTOMX THERAPEUTIC, INC. STATEMENTS OF STOCKHOLDERS' DEFICIT (in thousands, except share and per share data) Accumulated Additional Other Total Common Stock Paid-in Comprehensive Accumulated Stockholders' Shares Amount Capital Income/(Loss) Deficit Deficit Balance at December 31, 2021 65,392,758 $ 1 $ 623,344 $ ( 242 ) $ ( 623,562 ) $ ( 459 ) Exercise of stock options and release of RSUs 430,096 — 99 — — 99 Issuance of common stock under the Employee Stock Purchase Plan 405,192 — 549 — — 549 Stock-based compensation — — 13,125 — — 13,125 Other comprehensive income — — — 252 — 252 Net loss — — — — ( 99,317 ) ( 99,317 ) Balance at December 31, 2022 66,228,046 1 637,117 10 ( 722,879 ) ( 85,751 ) Exercise of stock options and release of RSUs 675,864 — 26 — — 26 Issuance of common stock under the Employee Stock Purchase Plan 406,928 — 535 — — 535 Issuance of pre-funded warrants and warrants, net of issuance cost — — 29,669 — — 29,669 Stock-based compensation — — 8,558 — — 8,558 Other comprehensive income — — — 85 — 85 Net loss — — — — ( 569 ) ( 569 ) Balance at December 31, 2023 67,310,838 $ 1 $ 675,905 $ 95 $ ( 723,448 ) $ ( 47,447 ) See accompanying notes to financial statements 91 CYTOMX THERAPEUTICS, INC. STATEMEN TS OF CASH FLOWS (in thousands) Year Ended December 31, 2023 2022 Cash flows from operating activities: Net loss $ ( 569 ) $ ( 99,317 ) Adjustments to reconcile net loss to net cash used in operating activities: Amortization of intangible assets 146 146 Depreciation and amortization 2,029 2,297 Impairment loss on machinery and equipment — 254 Accretion of discounts on short-term investments ( 7,419 ) ( 52 ) Stock-based compensation expense 8,558 13,125 Non-cash lease expense 3,729 3,413 Changes in operating assets and liabilities Accounts receivable 32,554 ( 35,196 ) Prepaid expenses and other current assets 2,471 ( 3,181 ) Other assets ( 56 ) 874 Accounts payable ( 1,426 ) 68 Accrued liabilities and other long-term liabilities ( 7,041 ) ( 9,784 ) Deferred revenue ( 89,011 ) 16,565 Net cash used in operating activities $ ( 56,035 ) $ ( 110,788 ) Cash flows from investing activities: Purchases of property and equipment ( 840 ) ( 1,740 ) Purchases of short term investments ( 424,834 ) — Maturities of short term investments 275,000 100,000 Net cash (used in) provided by investing activities $ ( 150,674 ) $ 98,260 Cash flows from financing activities: Proceeds from issuance of pre-funded warrants and warrants, net of issuance cost 29,669 — Proceeds from employee stock purchase plan and exercise of stock options 561 648 Net cash provided by financing activities $ 30,230 $ 648 Net decrease in cash, cash equivalents and restricted cash ( 176,479 ) ( 11,880 ) Cash, cash equivalents and restricted cash, beginning of year 194,567 206,447 Cash, cash equivalents and restricted cash, end of year $ 18,088 $ 194,567 Supplemental disclosures of noncash investing items: Purchases of property and equipment in accounts payable and accrued liabilities $ 75 $ 6 See accompanying notes to financial statements 92 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 1. Description of the Business CytomX Therapeutics, Inc. (the “Company”) is a clinical-stage, oncology-focused biopharmaceutical company developing potent biologics designed to be preferentially localized to tumors. 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 antibody-based 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 antibody-based drugs in the tumor microenvironment while minimizing drug activity in healthy tissues and in circulation. 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 financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). 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. Concentration of Credit Risk and Other Risks and Uncertainties The Company is subject to a number of risks similar to other biopharmaceutical companies in the early stage, including, but not limited to, the need to obtain adequate additional funding, possible failure of preclinical testing or clinical trials, the need to obtain marketing approval for its product candidates, competitors developing new technological innovations, the need to successfully commercialize and gain market acceptance of the Company’s products, and protection of proprietary technology. If the Company does not successfully obtain regulatory approval, commercialize or partner any of its product candidates, it will be unable to generate revenue from product sales or achieve profitability. Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents, short-term investments and accounts receivable. Substantially all the Company’s cash is held by one financial institution. Such deposits may, at times, exceed federally insured limits. The Company invests its cash equivalents in highly rated money market funds and its short-term investments in U.S. Treasury securities. Segments Management has determined that it has one business activity and operates as one operating segment as it only reports financial information on an aggregate basis to its Chief Executive Officer and Principal Financial Officer, who are the Company’s chief operating decision makers. All long-lived assets are maintained in the United States of America. Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments purchased with original maturities of three months or less at the date of purchase to be cash equivalents. Restricted cash represents a standby letter of credit issued pursuant to an office lease. 93 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets that sum to the total of the amounts shown in the statements of cash flows: December 31 2023 2022 (in thousands) Cash and cash equivalents $ 17,171 $ 193,650 Restricted cash - non-current assets 917 917 Total $ 18,088 $ 194,567 Investments All investments have been classified as available-for-sale (“AFS”) and are carried at fair value as determined based upon quoted market prices or pricing models for similar securities at period end. Investments that are required for use in current operations and that mature in less than 12 months are classified as short-term investments in the accompanying balance sheets. The amortized cost of securities is adjusted for amortization of premiums and accretion of discounts to maturity. Dividend and interest income are recognized when earned. Realized gains and losses are included in earnings and are derived using the specific identification method for determining the cost of securities sold. The Company assesses impairment of its AFS debt securities investments at each reporting period. Unrealized gains resulting from the excess of the fair value over the amortized cost basis of an investment are reported as a component of accumulated other comprehensive income (loss), net of tax. Unrealized losses or impairments resulting from the fair value of the AFS debt security being below the amortized cost basis are evaluated, using the discounted cash flow model, for identification of credit losses and non-credit related losses. Any credit losses are charged to earnings against the allowance for credit losses of the security, limited to the difference between the fair value and the amortized cost basis of the security. Any difference between the fair value of the security and the amortized cost basis, less the allowance for credit losses, are reported in other comprehensive income (loss). Expected cash inflows due to improvements in credit are recognized through a reversal of the allowance for credit losses subject to the total allowance previously recognized. In the event of impairment of any security, if management (i) has the intent to sell such security or (ii) will more-likely-than-not be required to sell such security before recovery of its amortized cost basis, such AFS debt security’s amortized cost basis will be written down to its fair value through earnings along with any existing allowance for credit losses. Property and Equipment, net Property and equipment are recorded at cost net of accumulated depreciation and amortization. Depreciation is provided using the straight-line method over the estimated useful lives of the respective assets. The useful lives of property and equipment are as follows: Machinery and equipment 5 years Computer equipment and software 3 years Furniture and fixtures 3 years Leasehold improvements Shorter of remaining lease term or estimated life of the assets Maintenance and repairs that do not extend the life or improve the asset are expensed when incurred. Goodwill and Intangible Assets Goodwill represents the excess of the purchase price paid over the fair value of tangible and identifiable intangible assets acquired in business combinations. Goodwill and other intangible assets with indefinite lives are not amortized, but are assigned to reporting units and tested for impairment annually, or whenever there is an impairment indicator. Intangible assets are comprised of in-process research and development. The Company assesses impairment indicators annually as of December 31 or more frequently, if a change in circumstances or the occurrence of events suggests the remaining value may not be recoverable. Intangible assets that are not deemed to have an indefinite life are amortized over their estimated useful lives. There was no impairment of goodwill or intangible assets identified during the years ended December 31, 2023 and 2022 . 94 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements Impairment of Long-Lived Assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset (or asset group) may not be recoverable and prior to any goodwill impairment test. An impairment loss is recognized when the total of estimated undiscounted future cash flows expected to result from the use of the asset (or asset group) and its eventual disposition is less than its carrying amount. Impairment, if any, would be assessed using discounted cash flows or other appropriate measures of fair value. During the year ended December 31, 2023, there was no impairment of long-lived assets. During the year ended December 31, 2022, the Company recorded an impairment loss of $ 0.3 million related to certain machinery and equipment. Revenue Recognition The Company’s revenues are primarily derived through its license, research, development and commercialization agreements. The terms of these types of agreements may include (i) licenses for the Company’s technology or programs, (ii) research and development services, and (iii) services or obligations in connection with participation in research or steering committees. Payments to the Company under these arrangements typically include one or more of the following: nonrefundable upfront and license fees, research funding, milestone and other contingent payments to the Company for the achievement of defined collaboration objectives and certain preclinical, clinical, regulatory and sales-based events, as well as royalties on sales of any commercialized products. The Company assesses whether the promises in its arrangements with customers are distinct performance obligations that should be accounted for separately. Judgment is required to determine whether the license to the Company’s intellectual property is distinct from the research and development services or participation on steering committees. The Company’s collaboration and license agreements may include contingent payments related to specified research, development and regulatory milestones. Such milestone payments are typically payable under the collaborations when the collaboration partner claims or selects a target, or initiates or advances a covered product candidate in preclinical or clinical development, upon submission for marketing approval of a covered product with regulatory authorities, or upon receipt of actual marketing approvals of a covered product or for additional indications. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At each reporting date, the Company re-evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price by using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price in such period of determination. The Company’s collaboration and license agreements may also include contingent payments related to sales-based milestones. Sales-based milestones are typically payable when annual sales of a covered product reach specified levels. Sales-based milestones are recognized at the later of when the associated performance obligation has been satisfied or when the sales occur. Unlike other contingency payments, such as regulatory milestones, sales-based milestones are not included in the transaction price based on estimates at the inception of the contract; instead, they are included when the sales or usage occur. The transaction price in each arrangement is allocated to the identified performance obligations based on the relative standalone selling price (“SSP”) of each distinct performance obligation, which requires judgment. In instances where SSP is not directly observable, such as when a license or service is not sold separately, SSP is determined using information that may include market conditions and other observable inputs. Due to the early stage of the Company’s licensed technology, the license of such technology is typically combined with research and development services and steering committee participation as one performance obligation. In the event that the Company receives non-cash consideration such as consideration in the form of a research license and research support services from the counterparty, the transaction price of a non-monetary exchange that has commercial substance is estimated based on the fair value of the non-cash consideration received, which may be determined through a valuation analysis. In certain cases, the Company’s performance creates an asset that does not have an alternative use to the customer and the Company has an enforceable right to payment at all times for performance completed to date. In these cases, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Any consideration payable to the Company’s customers is treated as a reduction to the transaction price and revenue, unless the payment to the customer is in exchange for distinct good and services. 95 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements Comprehensive Income (Loss) Comprehensive income (loss) represents all changes in stockholders’ equity (deficit) except those resulting from distributions to stockholders. The Company’s non-credit related unrealized gains and losses on investments during the period represent the component of other comprehensive income (loss) that is excluded from the reported net loss. Contract Balances Customer payments are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until the Company satisfies its performance obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional. Research and Development Expenses The Company records accrued liabilities for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical and clinical studies, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced, and includes these costs in accrued liabilities in the balance sheets and within research and development expense in the statements of operations. These costs are a significant component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers under the service agreements. The Company makes significant judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations. Research and development expenses include costs directly attributable to the conduct of research and development programs, including the cost of salaries, payroll taxes, employee benefits, materials, supplies, depreciation on and maintenance of research equipment, the cost of services provided by outside contractors, and the allocated portions of facility costs, such as rent, utilities, insurance, repairs and maintenance, depreciation, and general support services. All costs associated with research and development are expensed as incurred. Stock-based Compensation The Company measures compensation expense for all stock-based payment awards, including employee stock options, restricted stock units ("RSUs"), and employee stock purchases related to Employee Stock Purchase Plan ("ESPP") based on estimated fair values of the award at the grant date, and recognizes compensation expense over the requisite service vesting period. Stock options forfeitures are accounted for in the period in which they occur. To determine the fair value of a stock option award on the grant date, the Company uses the Black-Scholes option pricing model which consist of estimating variables such as the following. These estimates involve inherent uncertainties and the application of judgment. Expected term. The expected term of stock options represents the period that the stock options are expected to remain outstanding and is based on the Company's historical exercise experience with previously issued employee and board of directors' option grants. The expected term of the ESPP shares is equal to the six-month look-back period. Expected volatility. The expected stock price volatility for the Company’s stock options is based on the historical stock price volatility which is commensurate with the estimated expected term of the stock awards. Volatility for ESPP shares is equal to the Company’s historical volatility over a six-month offering period. Risk-free interest rate. The risk-free interest rate is based on the U.S. Treasury yield with a maturity equal to the expected term of the stock options in effect at the time of grant. Dividend yield. The expected dividend is assumed to be zero as the Company has never paid dividends and has no current plan to pay any dividends on its common stock. 96 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements The Company measures its restricted stock unit awards based on the market price of the Company’s common shares on the date of grant. Share-based compensation expense for performance-based awards is recognized when it becomes probable that the performance condition will be met. The Company reassesses the estimated probability at each reporting period, and if it is determined at a future date that a performance condition is probable of being achieved, the Company will recognize a cumulative catch-up adjustment and record the remaining expense ratably over the remaining requisite service period. Income Taxes The Company accounts for income taxes using an asset and liability approach. Deferred tax assets and liabilities reflect the net tax effects of temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The Company records a valuation allowance to reduce its deferred tax assets to reflect the net amount that it believes as more likely than not to be realized. Realization of the deferred tax assets is dependent on the generation of future taxable income, the amount and timing of which are uncertain. The valuation allowance requires an assessment of both positive and negative evidence when determining whether it is more likely than not that deferred tax assets are recoverable. Based upon the weight of available evidence at December 31, 2023, the Company continues to maintain a full valuation allowance against all of its deferred tax assets. The Company recognizes the tax effects of an uncertain tax position only if it is more likely than not that it will be sustained based solely on its technical merits as of the reporting date and only in an amount more likely than not that it will be sustained upon review by the tax authorities. The Company evaluates uncertain tax positions on a quarterly basis and adjust the liability for changes in facts and circumstances, such as new regulations or interpretations by the taxing authorities, new information obtained during a tax examination, significant amendment to an existing tax law, or resolution of an examination. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will impact the income tax provision in the period in which such determination is made. The resolution of its uncertain income tax positions is dependent on uncontrollable factors such as law changes, new case law, and the willingness of the income tax authorities to settle, including the timing thereof and other factors. Interest and/or penalties related to income tax matters are recognized as a component of income tax expense. Leases The Company determines if an arrangement is or contains a lease at inception. Operating leases are recorded as operating lease right-of-use (“ROU”) assets and operating lease liabilities in the Company’s balance sheet. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company uses an implicit rate when readily available, or its incremental borrowing rate based on the information available at lease commencement date in determining the present value of lease payments. The operating lease ROU assets also include any lease prepayments made and reduced by lease incentives. The Company’s lease terms may include options to extend the lease when it is reasonably certain that such option will be exercised. Lease expenses are recognized on a straight-line basis over the lease term. The Company elected the short-term lease recognition exemption. The Company’s operating lease arrangement includes lease and non-lease components which are generally accounted for separately. 3. Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period. Diluted net loss per share is the same as basic net loss per share since the effect of the potentially dilutive securities is anti-dilutive. Basic and diluted net loss per share attributable to common stockholders for the years ended December 31, 2023 and 2022 are calculated as follows (in thousands, except share and per share data): 97 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements Year Ended December 31, 2023 2022 Numerator: Net loss $ ( 569 ) $ ( 99,317 ) Denominator: Shares used to compute net loss per share, basic and diluted Weighted-average common shares outstanding 66,655,971 65,739,844 Weighted-average pre-funded warrants 7,152,266 — Weighted-average common shares outstanding used to calculate basic and diluted net loss per share 73,808,237 65,739,844 Net loss per share, basic and diluted Basic and Diluted $ ( 0.01 ) $ ( 1.51 ) The following weighted-average outstanding shares of potentially dilutive securities are excluded from the computation of diluted net loss per share for the periods presented, because including them would have been anti-dilutive: Year Ended December 31, 2023 2022 Options and ESPP to purchase common stock 13,805,472 14,292,729 Common stock warrants 5,675,167 — RSUs 1,820,589 1,201,058 Total 21,301,228 15,493,787 4. Fair Value Measurements and Investments In accordance with Accounting Standards Codification (“ASC”) 820-10, Fair Value Measurements and Disclosures, 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: • 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 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 equivalent or short-term investments. 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: December 31, 2023 Valuation Hierarchy Amortized Cost Unrealized Gains Aggregate Fair Value (in thousands) Assets Money market funds Level I $ 17,109 $ — $ 17,109 Restricted cash (money market funds) Level I 917 — 917 U.S. Treasury securities Level II 157,243 95 157,338 Total $ 175,269 $ 95 $ 175,364 98 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements December 31, 2022 Valuation Hierarchy Amortized Cost Unrealized Gains Aggregate Fair Value (in thousands) Assets Money market funds Level I $ 64,706 $ — $ 64,706 Restricted cash (money market funds) Level I 917 — 917 U.S. Treasury securities Level II 29,941 10 29,951 Total $ 95,564 $ 10 $ 95,574 As of December 31, 2023 , the remaining contractual terms of the U.S. Treasury securities are less than a year. 5. Property and Equipment Property and equipment, net consisted of the following: December 31 2023 2022 (in thousands) Laboratory equipment $ 14,119 $ 14,002 Computer equipment and software 1,125 1,942 Furniture and fixtures 1,051 1,054 Leasehold improvements 1,983 1,742 Construction in progress 368 705 18,646 19,445 Less: accumulated depreciation and amortization ( 14,688 ) ( 14,373 ) $ 3,958 $ 5,072 Depreciation and amortization expense was $ 2.0 million and $ 2.3 million for the years ended December 31, 2023 and 2022 , respectively. 6. Intangible Asset The intangible asset is being amortized over the estimated lives of the patents which average 12 years. The amortization expense for each of the years ended December 31, 2023 and 2022 was $ 0.1 million. December 31, 2023 2022 (in thousands) PROBODY platform intangible asset $ 1,750 $ 1,750 Less accumulated amortization ( 1,021 ) ( 875 ) $ 729 $ 875 99 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 7. Accrued Liabilities Accrued liabilities consisted of the following: December 31, 2023 2022 (in thousands) Research and clinical expenses $ 8,435 $ 13,089 Payroll and related expenses 8,160 8,060 Legal and professional expenses 690 1,413 Restructuring expenses — 1,627 Other accrued expenses 314 261 Total $ 17,599 $ 24,450 8. Collaboration and License Agreements The following table summarizes the revenue by collaboration partner: Year Ended December 31, 2023 2022 (in thousands) AbbVie $ 3,688 $ 18,563 Amgen 5,739 4,967 Astellas 24,453 20,491 Bristol Myers Squibb 49,300 9,142 Regeneron 7,194 — Moderna 10,840 — Total revenue $ 101,214 $ 53,163 AbbVie Ireland Unlimited Company In April 2016, the Company and AbbVie entered into two agreements, a CD71 Co-Development and Licensing Agreement (the “CD71 Agreement”) and a Discovery Collaboration and Licensing Agreement (as amended and restated in June 2019, the “Discovery Agreement” and together with the CD71 Agreement the “AbbVie Agreements”). Under the terms of the CD71 Agreement, the Company and AbbVie were co-developing a conditionally activated antibody-drug conjugate (“ADC”), CX-2029, against CD71, with the Company being responsible for preclinical and early clinical development. AbbVie was to be responsible for later development and commercialization, with global late-stage development costs shared between the two companies. The Company was to assume 35 % of the net profits or net losses related to later development and commercialization unless it opted-out. Under the Agreement, if the Company was to opt-out from participation of co-development of the CD71 conditionally activated ADC, which included CX-2029, AbbVie would have had the sole right and responsibility for the further development, manufacturing and commercialization of such CD71 conditionally activated ADC. Under the CD71 Agreement, t he Company has received in aggregate $ 100.0 million in upfront and milestone payments. AbbVie had entered into a license agreement with SGEN to license certain intellectual property rights pursuant to which the Company was required to pay SGEN sublicense fees for certain milestone achievements and an annual maintenance fee. These sublicense fees were treated as reductions to the transaction price and combined with the performance obligation to which they relate. In March 2023, the Company announced that it would evaluate the potential next steps for CX-2029 following the decision from AbbVie, to not advance CX-2029 into additional clinical studies. As a result of AbbVie’s decision, the 2016 CD71 License and Collaboration Agreement has been terminated and the Company re-acquired full rights to CX-2029. The Company has completed the performance obligation under the CD71 Agreement as of March 31, 2023 and recognized the related remaining deferred revenue of $ 4.0 million in the first quarter of 2023. 100 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements Under the terms of the Discovery Agreement, AbbVie received exclusive worldwide rights to develop and commercialize conditionally activated ADCs against up to two targets, one of which was selected in March 2017. AbbVie had the option to select a second target in exchange for a $ 10.0 million payment. The Company concluded that, at the inception of the agreement, AbbVie’s option to select the additional target was not a material right and did not represent a performance obligation of the agreement and would be accounted for as a separate arrangement upon exercise. The Company shall perform research services to discover the PROBODY therapeutics and create conditionally activated ADCs for the nominated collaboration targets. From that point, AbbVie shall have sole right and responsibility for development and commercialization of products comprising or containing such conditionally activated ADCs (“Discovery Licensed Products”). Under the Discovery Agreement, the Company received an upfront payment of $ 10.0 million for the first target in April 2016 and subsequently received an additional $ 10.0 million payment triggered by selection of the second target by AbbVie in June 2019. The second target was selected un der the Discovery Agreement that allowed AbbVie to select a target for developing a conditionally activated ADC or a PROBODY antibody. In December 2022, the Company completed the performance obligation for the second target earlier than the original research term projected to end in 2024 and recorded a cumulative change in estimate of $ 4.4 million. In December 2022, the research on the two discovery targets under the Discovery Agreement concluded with no plans to advance the discovery targets into clinical studies or to pursue new programs. The Discovery Agreement was also terminated in March 2023 by AbbVie and all target rights have reverted back to CytomX. The Company determined that the AbbVie Agreements should be combined and evaluated as a single arrangement in determining revenue recognition, because both agreements were concurrently negotiated and executed. Therefore, the Company concluded that there were two distinct performance obligations: (1) the CD71 Agreement performance obligation consisting of the CD71 Agreement research, development and commercialization license, related research services and participation in the joint research committee, and (2) the Discovery Agreement performance obligation consisting of the Discovery Agreement research, development and commercialization license, related research services and participation in the joint research committee. The total transaction price for the Discovery Agreement and CD71 Agreement, collectively, upon adoption of ASC 606 on January 1, 2018 of $ 39.8 million consisted of $ 30.0 million in upfront payments, and a $ 14.0 million milestone payment received under the CD71 Agreement (net of the payment of an associated sublicense fee of $ 1.0 million to SGEN), less $ 4.2 million of estimated sublicense fees. The upfront payments under the AbbVie Agreements were allocated between the two performance obligations based on the estimated relative standalone selling prices. The $ 30.0 million of upfront payments was allocated $ 20.0 million to the CD71 Agreement, with the remaining $ 10.0 million allocated to the Discovery Agreement. The $ 14.0 million milestone payment received (net of the payment of an associated sublicense fee of $ 1.0 million to SGEN) and the estimated sublicense fees of $ 4.2 million were allocated to the CD71 Agreement performance obligation as they are directly related to the development of the CX-2029. Therefore, of the $ 39.8 million total initial transaction price discussed above, the Company allocated $ 29.8 million to the CD71 Agreement performance obligation and $ 10.0 million to the Discovery Agreement performance obligation and recognized revenue using an input measure for each performance obligation. In applying the input method, revenue is recognized based on actual full time employee ("FTE") hours incurred as a percentage of total estimated FTE hours for completing the combined performance obligation over the estimated service period. The Company evaluated the measure of progress each reporting period and, if necessary, adjusted the measure of performance and related revenue recognition. The Company updated the transaction price for the CD71 Agreement performance obligation in May 2018, to include achievement of the $ 21.0 million milestone (net of the payment of an associated sublicense fee of $ 4.0 million to SGEN) and a revenue adjustment of $ 9.9 million was recognized in the second quarter of 2018 reflecting the percentage completed to-date on the project related to this milestone. The transaction price was updated again in March 2020 upon achievement of the $ 40.0 million milestone related to satisfaction of the CD71 dose escalation success criteria and $ 26.6 million was recognized as revenue related to this milestone reflecting the percentage completed to-date on the project as of March 2020. As of December 31, 2023 and 2022, deferred revenue related to the CD71 Agreement performance obligation was zero and $ 4.0 million respectively, and there were no deferred revenues related to the Discovery Agreement performance obligation, respectively. 101 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 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. 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 May 2023, CytomX and Amgen executed an amendment to the Amgen Agreement to extend the target selection period for Amgen to select its additional targets for research and development as further discussed below. Under the terms of the Amgen Agreement, as amended, the Company and Amgen will co-develop a conditionally activated T-cell engaging bispecific therapeutic targeting epidermal growth factor receptor (the “EGFR Products”). The Company is responsible for early-stage development of EGFR Products and Amgen will be responsible for late-stage development and commercialization of EGFR Products. Following early-stage development, the Company will have the right to elect to participate financially in the global co-development of EGFR Products with Amgen, during which the Company would bear a certain percentage of the worldwide development costs for EGFR Products and Amgen would bear the rest of such costs (the “EGFR Co-Development Option”). If the Company exercises its EGFR Co-Development Option, the Company will share in somewhat less than 50 % of the profit and losses from sales of such EGFR Products in the U.S., subject to certain caps, offsets, and deferrals. If the Company chooses not to exercise its EGFR Co-Development Option, the Company will not bear any costs of later stage development. The Company is also eligible to receive up to $ 460.0 million in development, regulatory, and commercial milestone payments for EGFR Products, and royalties in the low-double-digit to mid-teen percentage of worldwide commercial sales, provided that if the Company exercises its EGFR Co-Development option, it shall receive a profit and loss split of sales in the United States and royalties in the low-double-digit to mid-teen percentage of commercial sales outside of the United States. In January 2022, the IND for the EGFR product (CX-904) was allowed to proceed by the U.S. Food and Drug Administration (“FDA”). Amgen also has the right to select a total of up to three targets, including the two additional targets discussed below. The Company and Amgen collaborate in the research and development of conditionally activated T-cell engaging bispecifics therapies directed against such targets. Amgen has selected one such target (the “Amgen Other Product”). If Amgen exercises its option within a specified period of time, it can select two such additional targets (the “Amgen Option Products” and, together with the Amgen Other Product, the “Amgen Products”). Except with respect to preclinical activities to be conducted by CytomX, Amgen will be responsible, at its expense, for the development, manufacture, and commercialization of all Amgen Products. If Amgen exercises all of its options and advances all three of the Amgen Products, CytomX is eligible to receive up to $ 950.0 million in upfront, development, regulatory, and commercial milestones and tiered high single-digit to low-teen percentage royalties. T he Company concluded that, at the inception of the agreement and subsequent amendments, Amgen’s option to select the two additional targets is not a material right and does not represent a performance obligation of the agreement. At the initiation of the collaboration, CytomX had the option to select from programs specified in the Amgen Agreement, an existing preclinical stage T-cell engaging bispecific product from the Amgen preclinical pipeline. In March 2018, CytomX selected the program and this program is currently in preclinical development . CytomX is responsible, at its expense, for converting this program to a conditionally activated T-cell engaging bispecific 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. The Company considered the criteria for combining contracts in ASC 606 and determined that the Amgen Agreement and the Purchase Agreement should be combined into one contract. The Company accounted for the Amgen Agreement based on the fair values of the assets and services exchanged. For each of the EGFR Products and the Amgen Other Products, the Company determined that the respective promised goods and services identified, which are the research, development and commercialization license; the related research and development services and the participation in the joint steering committee and joint research committee, are not distinct. Therefore the identified promised goods and services were combined into one single performance obligation for each of the EGFR Product and the Amgen Other Products. 102 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements Furthermore, the Amgen Other Products are accounted for as a separate performance obligation from the EGFR Products as the nature of the services being performed is not the same and the value that Amgen can derive from one program is not dependent on the success of the other. The Company evaluates the measure of progress each reporting period using the input method and, if necessary, adjusts the measure of performance and related revenue recognition. Concurrent with the execution of the Amgen Agreement, the Company entered into a sublicense agreement whereby the Company granted Amgen a sublicense of its rights to one patent family that it co-owns with UCSB, that is exclusively licensed to the Company under the UCSB Agreement covering PROBODY antibodies and other pro-proteins in the fields of therapeutics, in vivo diagnostics and prophylactics. This sublicense was incremental to the patents, patent applications and know-how covering conditionally activated T-cell engaging bispecific molecules that were developed and owned by the Company and licensed to Amgen. Under the UCSB Agreement, as amended, the Company is obligated to make a sublicense payment to UCSB equal to up to 7.5 % of certain upfront and milestone payments owed to or received by the Company. The total transaction price of $ 51.2 million, consisting of the $ 40.0 million upfront payment, an estimated fair value of $ 10.7 million for the CytomX Product and $ 0.5 million of premium on the sale of the Company’s common stock, was allocated between the two performance obligations based on the relative standalone selling price of each performance obligation. To determine the standalone selling price, the Company used the discounted cash flow method by calculating risk-adjusted net present values of estimated cash flows. The Company determined that the remaining potential milestone payments were fully constrained due to the uncertainty in achieving them as of December 31, 2023. Of the $ 51.2 million total transaction price, the Company allocated $ 46.4 million to the EGFR Products performance obligation and $ 4.8 million to the Amgen Other Product performance obligations. The transaction price of each performance obligation was recognized using an input measure. In applying the input method of revenue recognition, the Company uses actual FTE hours incurred relative to estimated total FTE hours expected to be incurred for each combined performance obligation over the research service period. At the end of the second quarter of 2019, the Company determined that it would undertake additional testing and assessment of the molecules being evaluated under the EGFR project. As a result, the estimated FTE hours-to-completion and research service period related to the EGFR project were increased to eight years . In the second quarter of 2020, the Company completed the clinical candidate characterization phase and moved into the IND-enabling phase earlier than planned. As a result, the estimated FTE hours-to-completion and research service period related to the EGFR project were decreased from eight to approximately seven years . In the third quarter of 2022, the FDA initiated Project Optimus which is aimed to reform the dose optimization and dose selection paradigm. As a result, the estimated FTE hours-to-completion and research service period were increased by approximately an additional year. The $ 4.8 million transaction price allocated to the Amgen Other Product performance obligation is recognized using estimated FTE hours-to-completion over the estimated research service period of six years . As of December 31, 2023 and 2022 deferred revenue related to the EGFR Products performance obligation was $ 12.8 million and $ 18.0 million , respectively. As of December 31, 2023 and 2022, deferred revenue related to the Amgen Other Products performance obligation was zero and $ 0.6 million , respectively. 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 is comprised of an upfront fee of $ 80.0 million and contingent payments for development, regulatory and sales milestones of up to an aggregate of approximately $ 1.6 billion. The Company is also 103 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 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 FTE rate. The Company determined that the license and expertise related to the development of product candidates should be combined with the research and development services and participation in the joint research committee as one combined performance obligation for each collaboration target. The Company concluded, that at the inception of the agreement, Astellas’ Expansion Option for Additional Targets were not material rights and therefore not considered performance obligations. As such, each option would have been accounted for as a separate arrangement upon exercise. The initial transaction price of $ 103.2 million consists of the upfront fee of $ 80.0 million and estimated research and development fees of $ 23.2 million. The transaction price was allocated between the four performance obligations based on the relative standalone selling price of each performance obligation, which was deemed to be equal at the inception of the agreement. The Company determined that all potential milestone payments are constrained as of December 31, 2023 due to the significant uncertainty of achievement. The transaction price, as allocated to the combined performance obligation for each target, is recognized using an input measure. In applying the input method of revenue recognition, the Company uses actual FTE hours incurred relative to estimated total FTE hours expected to be incurred over the estimated research service period of each target. 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. The $ 5.0 million milestone payment was fully recognized in the first quarter of 2023 as the Company had completed its related performance obligation of the collaboration target which resulted in the clinical candidate nomination for further development. As of December 31, 2023 and 2022, deferred revenue relating to the Astellas Agreement was $ 31.0 million and $ 44.5 million , respectively. The amount due from Astellas under the Astellas Agreement was $ 2.2 million and $ 1.0 million as of December 31, 2023 and 2022, respectively. Bristol Myers Squibb Company On May 23, 2014, the Company and Bristol Myers Squibb Company (“Bristol Myers Squibb”) 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. 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. 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 (“Amendment Effective Date”). 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 104 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 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. The Company elected the practical expedient related to contract modifications upon adoption of ASC 606 and combined the original agreement and Amendment 1. The Company determined that the identified promised goods and services which include the exclusive research, development and commercialization license, the related research services and expertise for the development of the product candidates should be combined with the participation in the joint research committee as one combined performance obligation for each collaboration target. The Company also concluded that, at the inception of the agreement, Bristol Myers Squibb’s options for the third and fourth targets were material rights and performance obligations. As such, the material rights were accounted for as part of the initial transaction price. The Company received an upfront payment of $ 50.0 million from Bristol Myers Squibb in July 2014. In January and December 2016, Bristol Myers Squibb exercised the option to select the third and fourth targets, and paid the Company $ 10.0 million and $ 15.0 million, respectively, pursuant to the terms of the BMS Agreement. In December 2016, Bristol Myers Squibb selected a clinical candidate pursuant to the BMS Agreement, which triggered a $ 2.0 million pre-clinical milestone payment to the Company. In November 2017, the Company recognized a $ 10.0 million milestone payment from Bristol Myers Squibb upon approval of the investigational new drug application for the CTLA-4-directed PROBODY therapeutic. The initial transaction price for the BMS Agreement and Amendment 1, collectively, was $ 304.7 million consisting of the upfront fees of $ 250.0 million, target selection fees for the third and fourth targets of $ 25.0 million, estimated research and development service fees of $ 17.7 million and milestone payments received up to January 1, 2018, of $ 12.0 million. The Company determined that the remaining potential milestone payments were probable of significant revenue reversal as their achievement was highly dependent on factors outside the Company’s control. Therefore, these payments were fully constrained and were not included in the transaction price upon the adoption of ASC 606 on January 1, 2018. The initial transaction price for the combined obligation for each collaboration target is recognized using an input measure. In applying the input method of revenue recognition, the Company uses actual 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. During the first quarter of 2019, Bristol Myers Squibb terminated pre-clinical activities on three of the first four collaboration targets selected under the original 2014 BMS Agreement. The Company determined that upon the termination of pre-clinical activities on the three collaboration targets, it has no further obligations related to such targets. The Company accounted for the termination of the three targets as a modification and the related remaining unrecognized transaction price was reallocated to the remaining performance obligations. The Company continues to be obligated to perform research work under Amendment 1 executed in March 2017. In February 2020, Bristol Myers Squibb dosed the first patient in the Part 2 cohort expansion portion of its ongoing BMS-986249 clinical study for the CTLA-4 program, which triggered a $ 10.0 million milestone payment to the Company pursuant to the terms of the BMS Agreement. The $ 10.0 million milestone payment was recognized as revenue in the first quarter of 2020 as the Company had completed its performance obligation related to this collaboration target. 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 will continue 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. 105 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 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. As of December 31, 2023, the Company was eligible for up to approximately $ 2.1 billion in contingent payments for development, regulatory and sales milestones based on the ongoing collaboration projects, including for the CTLA-4 pro gram, with BMS. On March 6, 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 work on the CTLA-4 target under the collaboration. As of March 6, 2024, CytomX is eligible to receive approximately $1.8 billion in contingent payments for development, regulatory and sales milestones for the ongoing collaboration programs. The Company reevaluated the remaining potential milestone payments and determined that significant revenue reversal was probable as the achievement of such milestones was highly dependent on factors outside the Company’s control. As a result, these payments continued to be fully constrained and were not included in the transaction price on December 31, 2023. As of December 31, 2023, the Company has received in aggregate $ 297.0 million in upfront and milestone payments under the agreement. As of December 31, 2023 and 2022, deferred revenue relating to the BMS Agreement was $ 119.9 million and $ 169.2 million , respectively. 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. 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. The Moderna Agreement also provided Moderna with an option to participate in an equity financing by CytomX at market price, subject to certain terms, conditions and regulatory requirements. The Company determined that each collaboration program was a distinct performance obligation consisting of the exclusive research, development and commercialization license, research services, and participation in the joint steering committee. The initial transaction price is $ 51.7 million, consisting of the upfront fee of $ 30.0 million and estimated research funding of $ 21.7 million from Moderna. The initial transaction price excludes milestone payments as the achievement of such milestones is dependent on factors outside of the Company’s control and recognition would be probable of significant revenue reversal. As such, the milestones are fully constrained at the inception of the contract. The Company will re-evaluate the transaction price at each reporting date or as uncertain events are resolved or other changes in circumstances occur. The transaction price at the contract inception was allocated among the performance obligations using the SSP of each performance obligation, which was determined to be equal due to the early stage of the collaboration programs . The transaction price allocated to the collaboration programs is recognized using an input method. In applying the input measure of revenue recognition, the Company uses actual FTE hours incurred relative to estimated total FTE hours expected to be incurred for the respective collaboration program over an estimated service period of four years . As of December 31, 2023 and 2022, deferred revenue relating to the Moderna Agreement was $ 24.2 million and $ 35.0 million , respectively. The amount due from Moderna under the Moderna Agreement was $ 0 and $ 35.0 million as of December 31, 2023 and December 31, 2022, respectively. 106 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 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. The Company determined that each collaboration program was a distinct performance obligation consisting of an exclusive research, development and commercialization license, research and development services and participation in the joint research committee. The Company concluded that at the inception of the agreement, Regeneron’s Additional Collaboration Program Option did not include material rights and therefore was not a performance obligation. As such, each option will be accounted for as a separate arrangement upon exercise. The initial transaction price is $ 39.2 million consisting of the upfront fee of $ 30.0 million and estimated research and development service fees of $ 9.2 million. The initial transaction price excludes milestone payments as the achievement of such milestones is dependent on factors outside of the Company’s control and recognition would be probable of significant revenue reversal. As such, the milestones are fully constrained at the inception of the contract. The Company will re-evaluate the transaction price at each reporting date or as uncertain events are resolved or other changes in circumstances occur. The transaction price was allocated among the performance obligations using the SSP of each performance obligation, which was determined to be equal at the inception of the agreement. The transaction price allocated to each performance obligation is recognized using an input measure. In applying the input measure of revenue recognition, the Company uses actual FTE hours incurred relative to estimated total FTE hours expected to be incurred for the combined performance obligation over the estimated research service period of four years , which is projected to end in November 2026 . As of December 31, 2023 and 2022, deferred revenue relating to the Regeneron Agreement was $ 24.4 million and $ 30.0 million , respectively. The amount due from Regeneron under the Regeneron Agreement was $ 1.1 million and $ 0 million as of December 31, 2023 and December 31, 2022, respectively. Contract Liabilities The following table presents changes in the Company’s total contract liabilities for the years ended in December 31, 2023 and 2022 (in thousands): Deferred Revenue (in thousands) Balance at 12/31/2021 284,760 Additions 69,555 Revenue Recognized ( 52,989 ) Balance at 12/31/2022 301,326 Additions 6,438 Revenue Recognized ( 95,449 ) Balance at 12/31/2023 212,315 107 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements The Company expects that the $ 212.3 million of deferred revenue related to the following contracts as of December 31, 2023 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 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 $ 12.8 million of deferred revenue related to the Amgen EGFR Products is expected to be recognized until 2026 . • The $ 31.0 million of deferred revenue related to the Astellas Agreement is expected to be recognized until 2026 . • The $ 119.9 million of deferred revenue related to the BMS Agreement is expected to be recognized until 2025 . • The $ 24.2 million of deferred revenue related to the Moderna Agreement is expected to be recognized until 2027 . • The $ 24.4 million of deferred revenue related to the Regeneron Agreement is expected to be recognized until 2026 . 9. License Agreement UCSB The Company has an exclusive, worldwide license agreement with UCSB (the “UCSB Agreement”), 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. Pursuant to the UCSB Agreement, the Company is obligated to (i) make royalty payments to UCSB on net sales of its products covered under the agreement, subject to annual minimum amounts, (ii) make milestone payments to UCSB upon the occurrence of certain events, (iii) make a milestone payment to UCSB upon occurrence of an IPO or change of control, and (iv) reimburse UCSB for prosecution and maintenance of the licensed patents. If the Company sublicenses its rights under the UCSB Agreement, it is obligated to pay UCSB a percentage of the total sublicense revenue received, which total amount would be first reduced by the aggregate amount of certain research and development related expenses incurred by the Company and other permitted deductions. As part of the UCSB Agreement, the Company has annual minimum royalty obligations of $ 0.2 million under the terms of certain exclusive licensed patent rights. The royalty obligations are cancellable any time by giving notice to the licensor, with the termination being effective 60 days after giving notice. In April 2019, the Company entered into Amendment No.3 to the UCSB Agreement to adjust and clarify certain sublicense terms (“Amendment No.3”). In connection with the amendment, the Company issued to UCSB 150,000 shares of CytomX common stock with a fair value of $ 10.68 per share. Under the terms of Amendment No.3, the Company and UCSB agreed to modify the determination of sublicense revenues payable by the Company to UCSB on certain existing collaboration agreements and on collaboration agreements executed subsequent to Amendment No.3. In exchange, the Company agreed to make an upfront payment of $ 1.0 million as well as 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 2022, the Company incurred $ 0.1 million of sublicense fees triggered by the IND for the EGFR product and the dosing of the first patient of the EGFR program under the Amgen Agreement. In 2023, the Company incurred $ 0.2 million of sublicense fees triggered by achieving the clinical candidate milestone under the Astellas Agreement. During the years ended December 31, 2023 and 2022 , the Company incurred sublicense expenses of $ 1.1 million and $ 1.0 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 108 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 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. Seattle Genetics, Inc ("SGEN") In August 22, 2023, the Company entered into a Transition Agreement (the “Transition Agreement”) with AbbVie Global Enterprises Ltd. (“AbbVie”), pursuant to which the Company regained exclusive worldwide rights to develop CX-2029, a CD71-targeting conditionally activated antibody drug conjugate. The Transition Agreement supersedes the CD71 Co-Development and License Agreement (the “Collaboration Agreement”) entered into between the Company and AbbVie Ireland Unlimited Company (an affiliate entity of AbbVie) in 2016, that was terminated in May 2023, and grants certain intellectual property rights from AbbVie to enable the continued development of CX-2029 by Company for all human and nonhuman diagnostic, prophylactic, and therapeutic uses. Pursuant to the Transition Agreement, AbbVie is eligible to receive tiered sales royalties for CX-2029 ranging from the low-to-mid single digit percentages. CytomX will also pay SGEN potential future development, regulatory, and commercial milestones, and tiered sales royalties ranging from the mid-to-high single digits percentages related to certain CX-2029 linker payload technology licensed from SGEN. The Company’s royalty obligations for a particular CX-2029 product sold in any country shall continue until the later of (i) the date on which such CX-2029 product is no longer covered by certain patent rights in such country, (ii) the loss of regulatory exclusivity for such CX-2029 product in such country, or (iii) the tenth anniversary of the first commercial sale for such CX-2029 product in such country. Pursuant to the Transition Agreement, the Company will pay an annual exclusive license maintenance fee of $ 0.3 million starting 2023 through the date on which licensee receives first regulatory approval in the territory for the applicable licensed product. The Transition Agreement will continue in effect on a country-by-country basis until the expiration of the obligation to make payments under the Transition Agreement with respect to CX-2029 in each country, unless earlier terminated by either party pursuant to its terms. Either the Company or AbbVie may terminate the Transition Agreement for the other party’s insolvency or certain uncured breaches; the Company may terminate the Transition Agreement without cause; and AbbVie may terminate the Transition Agreement if the Company or any of its sublicensees or affiliates challenge certain SGEN patents. During the year ended December 31, 2023, the Company incurred sublicense expenses of $ 0.3 million under the provisions of the Transition Agreement. 10. Commitments and Contingencies Legal Proceedings On March 4, 2020 , Vytacera Bio, LLC filed a patent infringement lawsuit against the Company in the U.S. District Court for the District of Delaware. The lawsuit alleges that the Company's use, offers to sell, and/or sales of the PROBODY® technology platform for basic research applications constitutes infringement. The complaint seeks unspecified monetary damages. In September 2022, the Company filed a motion to dismiss the case and the Court granted the parties’ stipulation to stay all pending case deadlines until that motion is finally resolved. On October 30, 2023, Magistrate Judge Burke issued a Report & Recommendation that recommended granting Company’s motion to dismiss all counts of the complaint. In January 2024, the case was transferred to a new judge and the case will remain stayed pending a ruling by the trial judge on the Magistrate’s Report & Recommendation. The Company believes that the lawsuit is without merit and intends to vigorously defend itself. The Company does not believe a loss is probable and has no t recorded any amount as a contingent liability for claims associated with this lawsuit as of December 31, 2023. Indemnifications In the ordinary course of business, the Company enters into agreements that may include indemnification provisions. Pursuant to such agreements, the Company may indemnify, hold harmless and defend an indemnified party for losses suffered or incurred by the indemnified party. Some of the provisions will limit losses to those arising from third party actions. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments the Company could be required to make under these provisions is not determinable. The Company has never incurred material costs to defend lawsuits or settle claims related to these indemnification provisions. The Company has also entered into indemnification agreements with its directors and officers that may require the Company to indemnify its directors and officers against liabilities that may arise by reason of their status or service as directors or officers to the fullest extent permitted by Delaware corporate law. The Company currently has directors’ and officers’ insurance. 109 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 11. Leases Operating Lease In December 2015, the Company entered into a lease (the “2016 Lease”) of office and laboratory space located in South San Francisco, California for the Company’s corporate headquarters. The 2016 Lease has an initial term of ten years through 2026 and the Company has an option to extend the initial term for an additional five years at the then fair rental value as determined pursuant to the 2016 Lease. In addition, the Company obtained a standby letter of credit (the “Letter of Credit”) in an amount of approximately $ 0.9 million, which may be drawn by the Landlord to be applied for certain purposes upon the Company’s breach of any provisions under the 2016 Lease. The Company recorded the $ 0.9 million of cash securing the Letter of Credit as non-current restricted cash on its balance sheet as of December 31, 2023 and 2022. Rent expense during the years ended December 31, 2023 and 2022 was $ 5.1 million and $ 5.1 million, respectively. Supplemental information related to leases are as follows: Year Ended December 31, 2023 December 31, 2022 (in thousands) Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from operating leases $ 5,420 $ 5,273 December 31, 2023 December 31, 2022 (in thousands) Weighted-average remaining lease term (in years) Operating lease 2.75 3.75 Weighted-average discount rate Operating lease 8.25 % 8.25 % December 31, 2023 (in thousands) Maturity of operating lease liabilities 2024 5,572 2025 5,729 2026 4,387 Total lease payments 15,688 Less imputed interest ( 1,714 ) Present value of lease liabilities 13,974 In March 2023, the Company entered into a sublease agreement for a portion of its existing office and laboratory space. The sublease is classified as an operating lease whereby sublease income is recognized on a straight-line basis over the sublease term that expires on September 30, 2026. For the year ended December 31, 2023, sublease income was $ 0.9 million. December 31, 2023 (in thousands) Future sublease income payments 2024 1,333 2025 1,379 2026 1,067 Total sublease income payments $ 3,779 110 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements 12. Common Stock In June 2023, the Company entered into an agreement with BVF Partners L.P. (“BVF”) for a private placement 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, CytomX 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 following table summarizes the Company's outstanding warrants as of December 31, 2023: 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 Warrants Outstanding 14,423,077 $ 0.00001 5,769,231 $ 4.16 5,769,231 $ 6.24 The pre-funded warrants will expire in July 2043 , while Tranche 1 and Tranche 2 warrants will expire in July 2025 and July 2026 , respectively. 13. Stock-based Compensation The 2010 Plan and 2011 Plan In 2010, the Company adopted its 2010 Stock Incentive Plan (the “2010 Plan”) which provided for the granting of stock options to employees, directors and consultants of the Company. Options granted under the 2010 Plan were either incentive stock options (“ISOs”) or nonqualified stock options (“NSOs”). In February 2012, the Company adopted its 2011 Stock Incentive Plan (the “2011 Plan”). The 2011 Plan is divided into two separate equity programs, an option and stock appreciation rights grant program and a stock award program. In conjunction with adopting the 2011 Plan, the Company discontinued the 2010 Plan and released the shares reserved and still available under that plan. In connection with the consummation of the IPO in October 2015, the board of directors adopted the Company’s 2015 Equity Incentive Plan (the “2015 Plan” and collectively with the 2010 Plan and 2011 Plan, the “Plans”). In conjunction with adopting the 2015 Plan, the Company discontinued the 2011 Plan with respect to new equity awards. The 2015 Plan The 2015 Plan authorized the board of directors to grant incentive stock options, non-statutory stock options and RSUs to employees, directors, non-employee directors and consultants of the Company. Sto ck options under the 2015 Plan may be granted for periods of up to ten years . All stock options issued to date have had a 10 -year life. Under the terms of the 2015 Plan, stock options may be granted at an exercise price not less than the estimated fair value of the Company’s common stock on the date of grant, as determined by the Company’s board of directors. For employees holding more than 10 % of the voting rights of all classes of stock, the exercise price of ISOs and NSOs may not be less than 110 % of the estimated fair value of the shares on the date of grant, as determined by the board of directors. To date, stock options granted under the 2015 Plan generally vest over four years and vest at a rate of 25 % upon the first anniversary of the issuance date and 1/48 th per month thereafter. The initial number of shares of common stock available for future issuance under the 2015 Plan was 2,444,735 . Beginning on January 1, 2016 and continuing until the expiration of the 2015 Plan, the total number of shares of common stock available for issuance under the 2015 Plan will automatically increase annually on January 1 by 4 % of the total number of issued and outstanding shares of common stock as of January 1 of the same year. As of December 31, 2023 and 2022, 2,944,245 shares and 1,932,345 shares of common stock, respectively, were available for future issuance under the 2015 Plan. 111 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements The 2019 Plan In September 2019, the Board of Directors adopted the 2019 Employment Inducement Incentive Plan (the “2019 Plan”) which provides for the grant of stock options and other equity awards to any employee who has not previously been an employee or director of the Company or who is commencing employment with the Company following a bona fide period of nonemployment by the Company. Awards granted under the 2019 Plan are intended to constitute “employment inducement awards” under Nasdaq Listing Rule 5635(c)(4). Options granted under the 2019 Plan are nonqualified stock options (“NSOs”) which may be exercisable for periods of up to ten years and the options shall be granted at an exercise price of not less than 100 % of the fair market value of the Company’s common stock on the date of grant. The initial number of shares of common stock available for future issuance under the 2019 Plan was 1,815,000 . During 2021, t he total number of shares of common stock available for issuance under the 2019 Plan has increased by 1,000,000 shares. As of December 31, 2023 and 2022, 1,725,656 and 1,120,740 shares, respectively, of common stock were available for future issuance under the 2019 Plan. The following table summarizes the Company's stock option activities : Options Outstanding Number of Shares Weighted- Average Exercise Price Per Share Weighted- Average Remaining Contractual Life (years) Aggregate Intrinsic Value (in thousands) Balances at December 31, 2022 13,289,838 $ 7.67 Options granted 1,938,573 2.20 Options exercised ( 16,535 ) 1.57 $ 5.0 Options cancelled ( 2,262,264 ) 5.95 Balances at December 31, 2023 12,949,612 7.16 6.51 $ 70.5 Options Exercisable—December 31, 2023 8,672,013 $ 9.03 5.52 $ 4.7 The aggregate intrinsic values of options exercised, outstanding and exercisable were calculated as the difference between the exercise price of the options and the quoted market price of the underlying common stock as of December 31, 2023. As of December 31, 2023, the unrecognized compensation expense with respect to options granted was $ 8.2 million and is expected to be recognized over 2.23 years. Time-based RSUs ("TRSU") The following table summarizes the Company's TRSU activities: Number of Shares Weighted- Average Remaining Contractual Life (years) Aggregate Intrinsic Value (in thousands) Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2022 1,212,884 $ 2.81 RSUs awarded 724,342 2.30 RSUs vested ( 439,329 ) 3.16 RSUs cancelled ( 97,368 ) 3.41 Balance at December 31, 2023 1,400,529 0.94 $ 2,171 $ 2.40 The Company recorded $ 2.0 million and $ 1.2 million of stock-based compensation expense related to the TRSUs for the year ended December 31, 2023 and 2022, respectively. As of December 31, 2023 , the unrecognized compensation expense with respect to the TRSUs was $ 2.1 million which is expected to be recognized over 1.66 years. The TSRUs generally vest ratably over two to four years. 112 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements Performance-based RSUs ("PSU") In October 2021, the Company granted 435,000 PSUs to executive employees with an aggregated grant date fair value of $ 2.3 million. Vesting for 50% of the PSUs granted will occur upon achievement of certain specific milestones within one year of the grant date ("2021-Tranche 1") and the remaining 50% will vest upon achievement of additional company objectives within two years of the grant date ("2021-Tranche 2"). In July 2022, the Company determined that the performance condition for 2021-Tranche 1 was met and recorded $ 1.0 million of stock-based compensation expense for the year ended December 31, 2022. In September 2023, the performance condition for 2021-Tranche 2 was modified and the award was vested in in September 2023. As a result, the Company recorded $ 0.1 million of stock-based compensation expense for 2021-Tranche 2 for the three and nine months ended September 30, 2023 . In August 2022, the Company granted 250,000 PSUs to executive employees with an aggregated grant date fair value of approximately $ 0.4 million. Vesting for 50% of the PSUs granted will occur upon attaining certain specific milestones by December 2023 (“2022-Tranche 1”), and the remaining 50% will vest upon attaining certain specific milestones by December 2024 (“2022-Tranche 2”). In December 2023, the Company determined that the performance conditions for 2022-Tranche 1 was satisfied and the award was vested in December 2023. As a result, the Company recorded the remaining $ 128,000 c ompensation cost for the Tranche 1 award for the year ended December 31, 2023. For the year ended December 31, 2022, the Company recorded $ 55,000 c ompensation cost for the Tranche-1 award. As of December 31, 2023, the Company determined that it is probable that the performance conditions for 2022-Tranche 2 will be satisfied and recorded $ 106,000 compensation cost for the award 2023. 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 will occur 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”). The Company determined that it is not probable that the performance conditions will be satisfied for each of these tranches and no compensation cost was recorded for these awards through December 31, 2023. The following table summarizes the Company's PSU activities: Number of Shares Aggregate Intrinsic Value (in thousands) Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2022 383,750 $ 2.96 PSUs awarded 760,000 2.54 PSUs vested ( 220,000 ) 3.38 PSUs cancelled ( 48,750 ) 4.28 Balance at December 31, 2023 875,000 $ 1,356 $ 2.41 As of December 31, 2023, the unrecognized compensation expense with respect to PSUs granted was $ 2.0 million and is expected to be recognized over 1.43 years. Employee Stock Purchase Plan Concurrent with the completion of the IPO in October 2015, the Company’s Employee Stock Purchase Plan (“ESPP”) became effective. The ESPP allows eligible employees to purchase shares of the Company’s common stock at a discount through payroll deductions of up to 15 % of their eligible compensation, subject to any plan limitations. The ESPP generally provides for six-month offering periods, and at the end of each offering period, employees are able to purchase shares at 85 % of the lower of the fair market value of the Company’s common stock on the first trading day of the offering period or on the last trading day of the offering period. The Company issued 406,928 and 405,192 shares of common stock under the ESPP in 2023 and 2022, respectively. Shares available for future purchase under the ESPP were 939,698 shares and 1,346,626 shares at December 31, 2023 and 2022, respectively. The compensation expense related to the ESPP was $ 0.3 million, $ 0.6 million for the years ended December 31, 2023 and 2022, respectively. As of December 31, 2023, there was $ 0.1 million of unrecognized compensation cost related to the ESPP, which the Company expects to recognize over 5 months. 113 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements Stock Based Compensation Total stock-based compensation recorded related to stock options, TRSUs, PSUs and the ESPP was as follows (in thousands): Year Ended December 31, 2023 2022 Research and development $ 2,921 $ 5,544 General and administrative 5,637 7,581 Total stock-based compensation expense $ 8,558 $ 13,125 Fair Value Assumptions: The Company estimated the fair value of employee stock options and ESPP using the Black-Scholes valuation model based on the date of grant with the following weighted average assumptions: Options ESPP Year Ended December 31, Year Ended December 31, 2023 2022 2023 2022 Expected volatility 84 % 77 % 70 % 95 % Risk-free interest rate 4.2 % 2.4 % 5.4 % 2.9 % Dividend yield — — — — Expected term (in years) 5.1 4.6 0.5 0.5 Weighted average fair value per share $ 1.52 $ 1.77 $ 0.55 $ 0.67 14. Inco me Taxes The Company derives its income only from the United States. The components of the provision for income taxes are as follows (in thousands): Years Ended December 31, 2023 2022 Current: Federal $ — $ — State 3,892 — Total current 3,892 — Deferred: Federal — — State — — Total deferred — — Provision for income taxes $ 3,892 $ — A reconciliation of the Company’s effective tax rate to the statutory U.S. federal rate is as follows: Years Ended December 31, 2023 2022 U.S. federal taxes at statutory rate 21.0 % 21.0 % State tax, net of federal benefit ( 478.7 ) 1.7 Stock compensation 47.2 ( 2.1 ) Tax credits 242.7 2.4 Change in valuation allowance 283.2 ( 22.8 ) 162(m) limitation 1.2 ( 0.2 ) Other 0.5 - Total 117.1 % 0.0 % 114 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements The types of temporary differences that give rise to significant portions of the Company’s deferred income tax assets and liabilities are set out below (in thousands): Year Ended December 31, 2023 2022 Net operating loss carryforwards $ 56,767 $ 58,193 Research and development credits 22,149 24,700 Lease liability 3,501 3,802 Intangible assets 4,400 3,708 Deferred revenue 47,286 49,919 Accrued liabilities 2,425 1,504 Stock-based compensation 9,600 8,066 Sec 174 capitalized research and development costs 32,630 19,709 Other 55 31 Total gross deferred income tax assets 178,813 169,632 Less: valuation allowance ( 175,454 ) ( 166,037 ) Deferred tax assets, net of valuation allowance 3,359 3,595 Fixed assets ( 105 ) ( 43 ) Right-of-use assets ( 3,061 ) ( 3,358 ) Prepaid expenses ( 193 ) ( 194 ) Deferred tax liabilities ( 3,359 ) ( 3,595 ) Net deferred income tax liabilities $ — $ — The Company has established a valuation allowance against all of its net deferred tax assets. Management considered all available evidence, both positive and negative, including but not limited to our historical operating results, income or loss in recent periods, cumulative losses in recent years, forecasted earnings, future taxable income, and significant risk and uncertainty related to forecasts, and concluded the deferred tax assets are not more likely than not to be realized. The net change in the total valuation allowance for the years ended December 31, 2023 and 2022 was an increase of $ 9.4 million and $ 22.7 million, respectively. The Company had net operating loss carryforwards for federal and state income tax purposes of approximately $ 269.7 million and $ 26.7 million, respectively, as of December 31, 2023, available to reduce future taxable income. Of the federal net operating loss carryforwards, $ 65.6 million will begin to expire in 2034 , if not utilized and $ 204.1 million will carryforward indefinitely. The state net operating loss carryforwards will begin to expire in 2031 , if not utilized. The Company also has federal and state research and development tax credits carryforwards of $ 24.4 million and $ 13.7 million, respectively, as of December 31, 2023 available to reduce future income taxes. The federal research and development tax credits will begin to expire in 2031 if not utilized. The state research and development tax credits will carryforward indefinitely. I nternal Revenue Code section 382 (“IRC Section 382”) places a limitation (the “Section 382 Limitation”) on the amount of taxable income that can be offset by net operating loss (“NOL”) carryforwards after a change in control (generally greater than 50 % change in ownership) of a loss corporation. California has similar rules. The Company has performed an IRC Section 382 analysis and determined there was an ownership change in 2017 that resulted in 382 limitations. When an ownership change occurs, IRC Section 382 limits the use of NOLs and credits in subsequent periods based on the annual 382 limitations. The annual 382 limitations may limit the full use of available tax attributes in one year but the identified ownership changes may not result in expiration of tax attributes for use prior to expiration of their respective carryforward periods. Accordingly, none of the tax attributes have been reduced but limited the full use in 2018. The Company has determined that, while an ownership change has occurred, the applicable limits would not impair the value or anticipated use of the Company’s federal and state net operating losses. Although realization is not assured, management believes it is more likely than not that any limitation under IRC Section 382 will not impair the realizability of the deferred income tax assets related to federal and state net operating loss carryforwards. The Company updated its Section 382 analysis through the year ended December 31, 2023 and concluded no ownership changes occurred in current year which would result in a reduction of its net operating loss or in its research and development credits expiring unused. If additional ownership change occurs, the utilization of net operating loss and credit carryforwards could be significantly reduced. 115 CYTOMX THERAPEUTICS, INC. Notes to Financial Statements A reconciliation of the beginning and ending unrecognized tax benefit amount is as follows (in thousands): Year Ended December 31, 2023 2022 Balance at the beginning of the year $ 9,269 $ 7,780 Additions based on tax positions related to current year 527 1,391 Adjustment based on tax positions related to prior years 9,581 98 Balance at end of the year $ 19,377 $ 9,269 Of the unrecognized tax benefits as of December 31, 2023 and 2022, approximately $ 2.3 mill ion would affect the Company’s effective tax rate if recognized. Penalties and interest of $ 1.0 million and $ 0.6 million, respectively, have been accrued for the year ended December 31, 2023. 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 $ 3.9 million in long term liabilities for the proposed tax assessment, penalties and interest through December 31, 2023. Additional utilization of carryforward attributes and indirect federal tax effects of the assessment would result in a reduction in deferred tax assets of $ 5.1 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. 15. Defined Contribution Plan The Company sponsors a defined contribution plan under Section 401(k) of the Internal Revenue Code covering substantially all full-time U.S. employees. Employee contributions are voluntary and are determined on an individual basis subject to the maximum allowable under federal tax regulations. During the years ended December 31, 2023 and 2022, the Company made contributions to the plan o f $ 0.5 m illion, $ 0.9 million, respectively. 16. Restructuring On July 13, 2022, the Company announced a restructuring plan to prioritize its resources on its emerging pre-clinical and early clinical pipeline as well as its existing collaboration partnerships. The restructuring plan resulted in a reduction to its workforce of approximately 40 %. Restructuring costs of $ 2.4 million and $ 5.1 million were recorded in general and administrative expense and research and development expense, respectively, for the year ended December 31, 202 2. The restructuring was complete in the third quarter of 2023. The following is a summary of accrued restructuring costs as of December 31, 2023 and 2022 (in thousands): Severance and Benefits Costs Contract Termination Cost Total Balance at December 31, 2022 1,512 164 1,676 Cash payment ( 1,457 ) ( 50 ) ( 1,507 ) Change in estimates ( 55 ) ( 114 ) ( 169 ) Balance at December 31, 2023 $ — $ — $ — 116 Item 9. Changes in and Disagreements with Acco untants on Accounting and Financial Disclosure None. Item 9A. Control s and Procedures 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 Officer and Principal Financial Officer, has evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2023, the end of the period covered by this Annual Report on Form 10-K. Based on that evaluation, the Company's Principal Executive Officer and Principal Financial Officer concluded that, as of December 31, 2023, our disclosure controls and procedures were effective at a reasonable assurance level. Management’s Annual Report on Internal Control over Financial Reporting Management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Exchange Act Rules 13a-15(f) and 15d-15(f). Our internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of our assets; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of the financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures are being made only in accordance with authorizations of our management and directors; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of our assets that could have a material effect on the financial statements. Internal control over financial reporting is designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements prepared for external purposes in accordance with generally accepted accounting principles. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. Our management, with the participation of our Principal Executive Officer and Principal Financial Officer, conducted an evaluation of the effectiveness of our internal control over financial reporting based on the framework in Internal Control – Integrated Framework (2013 framework) issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on our evaluation under the framework in Internal Control – Integrated Framework, the Company's Principal Executive Officer and Principal Financial Officer concluded that, as of December 31, 2023, our internal control over financial reporting was effective. Remediation of Material Weakness In connection with preparing our financial statements for the year ending December 31, 2022 and evaluating new collaboration and license agreements initiated in the fourth quarter of 2022, we re-evaluated our previous application of ASC 606 for our collaboration and license agreements and identified an error. Upon reassessment, we have determined that certain revenue should be recognized over time using an input method as an appropriate measure of progress, rather than ratably over the estimated research period. The Company’s internal control to perform a technical accounting analysis for collaboration and license agreements failed to operate as designed. As a result, we concluded that the Company’s internal control over financial reporting was not effective as of December 31, 2022. The Company identified a material weakness in internal control over financial reporting related to its application of ASC 606 for license and collaboration agreements. 117 To remediate this material weakness, during the six months ended June 30, 2023, we have implemented and improved the operation of our controls related to the application of ASC 606 to our collaboration and license agreements and the related controls to measure the progress in satisfying the performance obligations. Management has determined that the material weakness was remediated during the three months ended June 30, 2023, due to enhancements made to our related technical accounting analysis processes and internal controls during the period. Changes in Internal Control 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 December 31, 2023, that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting. Item 9B. Othe r Information (a). On March 6, 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 work on the CTLA-4 target under the collaboration. CytomX’s ongoing research collaboration with Bristol Myers Squibb, which includes multiple ongoing preclinical programs, including T-cell engagers, will continue . Item 9C. Disclosure Regarding Foreign Jurisdictions That Prevent Inspections None. 118 PART III Item 10. Directors, Executive Of ficers and Corporate Governance The information required by this Item will be set forth in the Company’s proxy statement to be filed with the Securities and Exchange Commission within 120 days after the Company’s fiscal year end and is incorporated herein by reference. We have adopted a code of business conduct and ethics that applies to all employees, including our Principal Executive Officer, Principal Financial Officer, Principal Accounting Officer or Controller, or persons performing similar functions. The code of business conduct and ethics is available on our website at www.cytomx.com. Amendments to, and waivers from, the code of business conduct and ethics that apply to any director, executive officer or persons performing similar functions will be disclosed at the website address provided above and, to the extent required by applicable regulations, on a Current Report on Form 8-K filed with the SEC. Item 11. Executi ve Compensation The information required by this Item will be set forth in the Company’s proxy statement to be filed with the Securities and Exchange Commission within 120 days after the Company’s fiscal year end and is incorporated herein by reference. Item 12. Security Ownership of Certain Beneficial Ow ners and Management and Related Stockholder Matters The information required by this Item will be set forth in the Company’s proxy statement to be filed with the Securities and Exchange Commission within 120 days after the Company’s fiscal year end and is incorporated herein by reference. Item 13. Certain Relationships and Relate d Transactions and Director Independence The information required by this Item will be set forth in the Company’s proxy statement to be filed with the Securities and Exchange Commission within 120 days after the Company’s fiscal year end and is incorporated herein by reference. Item 14. Principal Accou ntant Fees and Services The information required by this Item will be set forth in the Company’s proxy statement to be filed with the Securities and Exchange Commission within 120 days after the Company’s fiscal year end and is incorporated herein by reference. 119 PART IV Item 15. Exhibits and Financial Statement Schedules (1) Financial Statements: The financial statements required by Item 15(a) are filed as part of this Annual Report on Form 10-K under Item 8 “Financial Statements and Supplementary Data.” (2) Financial Statement Schedules The financial statement schedules required by Item 15(a) are omitted because they are not applicable, not required or the required information is included in the financial statements or notes thereto as filed in Item 8 of this Annual Report on Form 10-K. (3) Exhibits. Incorporated by Reference Exhibit Number Exhibit Description Form Date Number Filed Herewith 1.1 Open Market Sale Agreement, dated as of February 27, 2020, by and between CytomX Therapeutics, Inc. and Jefferies LLC. 10-K 2/27/2020 1.1 3.1(a) Amended and Restated Certificate of Incorporation. 8-K 10/19/2015 3.1 3.1(b) Certificate of Amendment to Amended and Restated Certificate of Incorporation of CytomX Therapeutics, Inc. 8-K 6/23/2020 3.1 3.2 Amended and Restated Bylaws. 8-K 10/19/2015 3.2 4.1 Reference is made to exhibits 3.1 through 3.2. 4.2 Specimen Common Stock Certificate. S-1/A 9/28/2015 4.1 4.3 Registration Rights Agreement dated as of September 29, 2017 by and between CytomX Therapeutics, Inc. and Amgen, Inc. 10-Q 11/7/2017 4.4 4.4 Description of Registrant’s Securities Registered Pursuant to Section 12 of the Securities Exchange Act of 1934. 10-Q 8/6/2020 4.4 4.5 Form of Pre-Funded Warrant 8-K 7/3/2023 4.1 4.6 Form of Tranche Warrant 8-K 7/3/2023 4.2 10.1(a)# 2010 Stock Incentive Plan adopted on September 21, 2010 (“2010 Plan”). S-1 8/28/2015 10.3 10.1(b)# Form of Stock Option Agreement under the 2010 Plan. S-1 8/28/2015 10.4 10.2(a)# 2011 Stock Incentive Plan, adopted on February 7, 2012, as amended (“2011 Plan”). S-1 8/28/2015 10.1 10.2(b)# Form of Restricted Stock Award Agreement and Option Exercise Agreement under the 2011 Plan. S-1 8/28/2015 10.2 10.3(a)# 2015 Equity Incentive Plan (“2015 Plan”). S-1/A 10/6/2015 10.5 10.3(b)# Form of 2015 Plan Option Agreement under the 2015 Plan. 10-Q 11/23/2015 10.4 10.3(c)# Form of 2015 Plan Early Exercise Option Agreement 10-Q 11/23/2015 10.5 120 10.3(d)# Form of 2015 Plan Restricted Share Unit Award Grant Notice and Agreement 10-K 3/21/2022 10.3(d) 10.4(a)# 2019 Employment Inducement Incentive Plan adopted on September 18, 2019 (“2019 Plan”). 10-Q 11/7/2019 10.1 10.4(b)# Form of Stock Option Agreement under the 2019 Plan. 10-Q 11/7/2019 10.2 10.5# 2015 CytomX Therapeutics, Inc. Employee Stock Purchase Plan. S-1/A 9/28/2015 10.6 10.6# Form of Indemnification Agreement by and between CytomX Therapeutics, Inc. and each of its directors and each of its executive officers. S-1 8/28/2015 10.16 10.7# Employment Offer Letter Agreement between CytomX Therapeutics, Inc. and Sean A. McCarthy, D. Phil, dated as of December 15, 2010. S-1 8/28/2015 10.7 10.8# Employment Offer Letter Agreement between CytomX Therapeutics, Inc. and Jeffrey Landau dated as of March 31, 2021. 10-Q 8/8/2023 10.3 10.9# Amended and Restated Severance and Change of Control Agreement dated February 27, 2019, by and between CytomX Therapeutics, Inc. and Sean McCarthy. D. Phil. 10-Q 5/9/2019 10.1 10.10# Amended and Restated Severance and Change of Control Agreement dated March 25, 2019, by and between CytomX Therapeutics, Inc. and Lloyd Rowland. 10-Q 5/9/2019 10.2 10.11# Form of Amended and Restated Severance and Change of Control Agreement by and between CytomX Therapeutics, Inc. and each of its executive officers other than Sean A. McCarthy. 10-Q 8/8/2023 10.2 10.12(a) Lease dated as of December 10, 2015, by and between CytomX Therapeutics, Inc. and HCP Oyster Point III LLC. 8-K 12/16/2015 10.1 10.12(b) Sublease Agreement dated as of March 24, 2023, by and between CytomX Therapeutics, Inc and Atomic AI, Inc. 10-Q 5/9/2023 10.1 10.13(a) Exclusive License Agreement dated as of August 19, 2010, by and between The Regents of the University of California and CytomX Therapeutics, Inc., as amended by Amendment No. 1 to Exclusive Agreement effective as of May 30, 2013 and Amendment No. 2 to Exclusive Agreement effective as of November 8, 2013. S-1/A 9/18/2015 10.21 10.13(b)†† Amendment No.3 to Exclusive License Agreement effective as of April 2, 2019, by and between CytomX Therapeutics, Inc. and The Regents of the University of California. 10-Q 5/9/2019 10.6 10.14(a)† Collaboration and License Agreement dated as of May 23, 2014, by and between CytomX Therapeutics, Inc. and Bristol Myers Squibb Company. 10-Q 11/5/2020 10.2 10.14(b)† Amendment to Extend Collaboration and License Agreement, dated March 17, 2017, by and between the Company and Bristol Myers Squibb. 10-Q 5/5/2017 10.1 121 10.14(c)† Amendment No 2 to Collaboration and License Agreement, as amended, dated March 17, 2017, by and between the Company and Bristol Myers Squibb, effective as of February 22, 2021. 10-Q 5/6/2021 10.2 10.14(d)† Amendment No 3 to Collaboration and License Agreement, dated May 23, 2014, by and between the Company and Bristol Myers Squibb Company, effective as of October 11, 2022. 10-Q 11/8/2022 10.6 10.15(a)† Co-Development and License Agreement, dated April 21, 2016, by and between CytomX Therapeutics, Inc. and AbbVie Ireland Unlimited Company. 10-Q 8/3/2016 10.1 10.15(b)† First Amendment to the CD71 Co-Development and License Agreement by and between CytomX Therapeutics, Inc. and AbbVie Ireland Unlimited Company, dated as of October 5, 2016. 10-Q 11/6/2018 10.1 10.15(c)† Second Amendment to the CD71 Co-Development and License Agreement by and between CytomX Therapeutics, Inc. and AbbVie Ireland Unlimited Company, effective as of March 31, 2017. 10-Q 11/6/2018 10.2 10.15(d)† Third Amendment to the CD71 Co-Development and License Agreement by and between CytomX Therapeutics, Inc. and AbbVie Ireland Unlimited Company, effective as of January 3, 2018. 10-Q 11/6/2018 10.3 10.15(e)† Amended and Restated Discovery Collaboration and License Agreement, dated as of June 28, 2019, by and between CytomX Therapeutics, Inc., and AbbVie Ireland Unlimited Company. 10-Q 8/7/2019 10.1 10.15(f)†† Transition Agreement effective as of August 22, 2023 by and between CytomX Therapeutics, Inc., and AbbVie Global Enterprises Ltd. 10-Q 11/7/2023 10.1 10.16(a)†† Collaboration and License Agreement by and between CytomX Therapeutics, Inc. and Amgen, Inc. dated as of September 29, 2017. 10-Q 11/7/2017 10.1 10.16(b)† Amendment No. 1 to the Collaboration and License Agreement, dated as of September 29, 2020, by and between CytomX Therapeutics, Inc. and Amgen, Inc. 10-Q 11/5/2020 10.3 10.16(c)†† Amendment No. 2 to the Collaboration and License Agreement, dated as of October 27, 2021, by and between CytomX Therapeutics, Inc. and Amgen, Inc. 10-Q 11/5/2020 10.3 10.16(d)†† Amendment No. 3 to the Collaboration and License Agreement, dated as of May 18, 2023, by and between CytomX Therapeutics, Inc. and Amgen, Inc. 10-Q 8/8/2023 10.1 10.17†† Collaboration and License Agreement dated as of March 23, 2020, by and between CytomX Therapeutics, Inc. and Astellas Pharma Inc. 10-Q 5/7/2020 10.4 10.18(a)† Research Collaboration Agreement dated as of January 8, 2014, by and between ImmunoGen, Inc. and CytomX Therapeutics, Inc., as amended by the First Amendment to Research Collaboration Agreement effective as of April 3, 2015. S-1/A 10/2/2015 10.17 10.18(b)† Second Amendment to the Research Collaboration Agreement by and between CytomX Therapeutics, Inc. and ImmunoGen Inc., dated as of February 12, 2016 10-Q 11/6/2018 10.5 10.18(c)† Third Amendment to the Research Collaboration Agreement by and between CytomX Therapeutics, Inc. and ImmunoGen Inc., dated as of March 3, 2017. 10-Q 11/6/2018 10.6 122 10.19† License Agreement by and between CytomX Therapeutics, Inc. and ImmunoGen Inc., dated as of February 12, 2016. 10-Q 11/6/2018 10.4 10.20†† Collaboration and License Agreement dated as of November 16, 2022 by and between CytomX Therapeutics, Inc. and Regeneron Pharmaceuticals, Inc. 10-K 3/27/2023 10.24 10.21†† Collaboration and License Agreement dated as of December 30, 2022 by and between CytomX Therapeutics, Inc. and ModernaTX, Inc. 10-K 3/27/2023 10.25 10.22#†† Consulting Agreement effective as of December 14, 2020, by and between CytomX Therapeutics, Inc and Dr. W. Michael Kavanaugh. 10-K 2/24/2021 10.24 10.23# Retirement Agreement by and between CytomX Therapeutics, Inc and Dr. W. Michael Kavanaugh, dated as of December 1, 2020. 10-K 2/24/2021 10.25 10.24# Consulting Agreement, effective as of April 1, 2021, by and between CytomX Therapeutics, Inc. and Dr. Charles Fuchs. 10-Q 5/6/2021 10.3 10.25 Consulting Agreement effective as of October 1, 2022, by and between CytomX Therapeutics, Inc. and Carlos Campoy. 10-Q 11/8/2022 10.1 10.26 Consulting Agreement effective as of September 13, 2022, by and between CytomX Therapeutics, Inc. and Amy C. Peterson, M.D. 10-Q 11/8/2022 10.2 10.27 Unit Purchase Agreement by and among the CytomX Therapeutics, Inc. and certain accredited investors named therein, dated June 29, 2023. 8-K 7/3/2023 10.1 19.1 Corporate Securities Trading Policy X 23.1 Consent of Independent Registered Public Accounting Firm. X 24.1 Power of Attorney (included on signature page) X 31.1 Certification of Principal Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. X 31.2 Certification of Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. X 32.1** Certification of Principal Executive Officer and Principal Financial Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. X 97.1 Executive Compensation Clawback Policy X 101.INS Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document X 101.SCH Inline XBRL Taxonomy Extension Schema Document X 101.CAL Inline XBRL Taxonomy Extension Calculation Linkbase Document X 101.DEF Inline XBRL Taxonomy Extension Definition Linkbase Document X 101.LAB Inline XBRL Taxonomy Extension Label Linkbase Document X 101.PRE Inline XBRL Taxonomy Extension Presentation Linkbase Document X 123 104 Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101) X † Confidential treatment has been granted for certain information contained in this exhibit. Such information has been omitted and filed separately with the Securities and Exchange Commission. †† Certain confidential portions of this exhibit have been omitted from this exhibit. # Indicates management contract or compensatory plan. ** The certifications attached as Exhibit 32.1 that accompany this Annual Report on Form 10-K are not deemed filed with the Securities and Exchange Commission and are not to be incorporated by reference into any filing of CytomX Therapeutics, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date of this Annual Report on Form 10-K, irrespective of any general incorporation language contained in such filing. Item 16. Form 10-K Summary Registrants may voluntarily include a summary of information required by Form 10-K under Item 16. We have elected not to include such summary. 124 SIGNAT URES Pursuant to the requirements of Section 13 or 15(d) the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. CytomX Therapeutics, Inc. Date: March 11, 2024 By: /s/ Sean A. McCarthy Name: Sean A. McCarthy, D.Phil. Title: Chief Executive Officer and Chairman (Principal Executive Officer) By: /s/ Christopher W. Ogden Name: Christopher W. Ogden Title: Senior Vice President, Finance and Accounting (Principal Financial Officer and Principal Accounting Officer) 125 POW ER OF ATTORNEY Each person whose individual signature appears below hereby authorizes and appoints Sean A. McCarthy, D. Phil. and Lloyd Rowland and each of them, with full power of substitution and resubstitution, as his or her true and lawful attorney-in-fact and agent to act in his or her name, place and stead and to execute in the name and on behalf of each person, individually and in each capacity stated below, and to file any and all amendments to this Annual Report on Form 10-K and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorney-in-fact and agents full power and authority to do and perform each and every act and thing, ratifying and confirming all that said attorney-in-fact and agents or his substitute or substitutes may lawfully do or cause to be done by virtue thereof. Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated. /s/ Sean A. McCarthy Chief Executive Officer and Director March 11, 2024 Sean A. McCarthy, D.Phil. (Principal Executive Officer) /s/ Matthew P. Young Director March 11, 2024 Matthew P. Young /s/ Alan Ashworth Director March 11, 2024 Alan Ashworth, Ph.D. FRS /s/ Elaine V. Jones Director March 11, 2024 Elaine V. Jones, Ph.D. /s/ James R. Meyers Director March 11, 2024 James R. Meyers /s/ Mani Mohindru Director March 11, 2024 Mani Mohindru, Ph.D. /s/ Halley E. Gilbert Director March 11, 2024 Halley E. Gilbert 126