8. Collaboration and License Agreements

Amgen, Inc.

On September 29, 2017, the Company and Amgen, Inc. (“Amgen”) entered into a Collaboration and License Agreement (the “Amgen Agreement”). Pursuant to the Amgen Agreement, the Company received an upfront payment of $40.0 million in October 2017. Concurrent with the Amgen Agreement, the Company and Amgen entered into a Share Purchase Agreement pursuant to which Amgen purchased 1,156,069 shares of the Company’s common stock at a price of $17.30 per share for total proceeds of $20.0 million.

Under the terms of the Amgen Agreement, as amended, the Company and Amgen were co-developing a conditionally activated T-cell engager (“TCE”) targeting epidermal growth factor receptor (the “EGFR Products”). The Company was responsible for early-stage development of EGFR Products and Amgen was to be responsible for late-stage development and commercialization of EGFR Products. Following potential advancement beyond early-stage development, the Company had the right to elect to participate financially in the global co-development of EGFR Products with Amgen, during which the Company would have been responsible for a certain percentage of the worldwide development costs and entitled to certain percentage of profit sharing in the U.S., for EGFR Products. In addition, the Company was also eligible to receive up to $460.0 million in development, regulatory, and commercial milestone payments for EGFR Products, and royalties in certain percentages of worldwide commercial sales.

In October 2021, CytomX and Amgen executed an amendment to the Amgen Agreement primarily to (1) extend the target selection date for Amgen to select its additional targets for research and development, and (2) reduce the total number of milestone events and increase the total amount of milestone payments for EGFR Products. In each of May 2023 and March 2024, CytomX and Amgen executed an amendment to the Amgen Agreement to extend the target selection period for Amgen to select its additional targets.

Amgen had the right to select a total of up to three targets, including the two additional targets. The Company and Amgen collaborated in the research and development of conditionally activated T-cell engaging bispecifics therapies directed against such targets. Amgen had selected one such target (the “Amgen Other Product”). Except with respect to preclinical activities to be conducted by CytomX, Amgen would have been responsible, at its expense, for the development, manufacture, and commercialization of all Amgen Products. The 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.

In January 2022, the IND for the EGFR product (“CX-904”) was allowed to proceed by the U.S. Food and Drug Administration (“FDA”) and the program progressed into Phase 1 dose escalation. In March 2025, CytomX and Amgen jointly decided to not continue CX-904 development and Amgen terminated its license to the EGFR Products. As a result, all of the remaining deferred revenue of the EGFR product was recognized in the first quarter of 2025 due to Amgen terminating its license to the EGFR Product effective May 2025. In April 2025, the Amgen Other Product was also terminated with 60 days written notice pursuant to the Amgen Agreement. The Amgen research collaboration remains in effect with the current scope being the preclinical TCE that CytomX selected from Amgen’s preclinical pipeline further discussed below.

At the initiation of the collaboration, CytomX had the option to select from programs specified in the Amgen Agreement, an existing preclinical stage TCE product from the Amgen preclinical pipeline. In March 2018, CytomX selected the program and this program, CX-908, a PROBODY® T cell engager targeting CDH3 and CD3, is currently in preclinical development. CytomX is responsible, at its expense, for converting this program to a conditionally activated TCE product, and thereafter, will be responsible for development, manufacturing, and commercialization of the product (“CytomX Product”). Amgen is eligible to receive up to $203.0 million in development, regulatory, and commercial milestone payments for the CytomX Product, and tiered mid-single digit to low double-digit percentage royalties.

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.

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.

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 certain conditionally activatable antibodies 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.

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 full-time employee (“FTE”) hours incurred relative to estimated total FTE hours expected to be incurred for each combined performance obligation over the research service period. The $4.8 million transaction price allocated to the Amgen Other Product performance obligation was recognized using estimated FTE hours-to-completion over the estimated research service period of six years.

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. As of June 30, 2025, the Company had completed its performance obligations related to the EGFR Products and the Amgen Other Products and recognized the remaining deferred revenue. As of December 31, 2024, deferred revenue related to the EGFR Products performance obligation was $9.7 million and was immaterial for the Amgen Other Products.

Astellas Pharma Inc.

The Company and Astellas Pharma, Inc. (“Astellas”) entered into a Collaboration and License Agreement (the “Astellas Agreement”) on March 23, 2020, the effective date, to collaborate on preclinical research activities to discover and develop certain antibody compounds for the treatment of cancer using the Company’s PROBODY therapeutic technology.

Under the terms of the Astellas Agreement, the Company granted Astellas an exclusive, worldwide right to develop and commercialize PROBODY therapeutics for up to four collaboration targets including one initial target and three additional targets (“Additional Targets”). In addition, Astellas had the right to expand the number of Additional Targets from three up to five (the “Expansion Option”) before the third anniversary of the effective date. Furthermore, for a specified number of targets, at a pre-specified time prior to the initiation of the first pivotal study of a product against such target, the Company had the option to 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, also provided the option for the Company to co-commercialize such product in the United States. The Company had not considered the Cost Share Option as a performance obligation at the inception of the agreement as participation is at the Company’s discretion.

Pursuant to the Astellas Agreement, the consideration from Astellas was comprised of an upfront fee of $80.0 million and total potential contingent payments for development, regulatory and sales milestones of up to an aggregate of approximately $1.2 billion. The Company was also entitled to tiered royalties from high-single digit to mid-teen percentage royalties from potential future sales. Astellas was responsible for all preclinical research costs incurred by either party as set forth in the preclinical research plan and the Company was entitled to receive research and development service fees based on a prescribed FTE rate.

The Company had 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, 2025 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 achieved a clinical candidate milestone for the first collaboration target nomination under the Astellas Agreement which triggered a $5.0 million milestone payment to the Company which was fully recognized in the first quarter of 2023 as the Company had completed its related performance obligation. In March 2024, the Company achieved the good laboratory practices ("GLPs") toxicology milestone for this candidate which triggered a $5.0 million milestone payment to the Company. The $5.0 million milestone payment was fully recognized in the first quarter of 2024 as the Company had completed its related performance obligation of this first collaboration target. Also, in March 2024, the Company achieved a clinical candidate milestone for a second collaboration target nomination under the Astellas Agreement which triggered an additional $5.0 million milestone

payment to the Company. The $5.0 million milestone payment for this second nomination was fully recognized in the first quarter of 2024 as the Company had completed its related performance obligation. In the first quarter of 2025, Astellas initiated GLP toxicology studies for the second collaboration target, triggering a $5.0 million milestone payment to CytomX. The $5.0 million milestone payment was fully recognized in the first quarter of 2025 as the Company had completed its related performance obligation of this second collaboration target.

As of December 31, 2025 and 2024, deferred revenue relating to the Astellas Agreement was $8.6 million and $17.4 million, respectively. The amount due from Astellas under the Astellas Agreement was $0.9 million and $1.1 million as of December 31, 2025 and 2024, respectively. In the first quarter of 2026, Astellas chose not to advance the remaining preclinical programs which will result in the completion of CytomX’s performance obligation and recognition of the remaining deferred revenue by the second quarter of 2026.

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, including the target CTLA-4. The effective date of the BMS Agreement was July 7, 2014.

Under the terms of the BMS Agreement, the Company granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize PROBODY therapeutics for up to four oncology targets. Bristol Myers Squibb had additional rights to substitute up to two collaboration targets within three years of the effective date of the BMS Agreement. These rights expired in May 2017. Each collaboration target had a two-year research term and the two additional targets had to be nominated by Bristol Myers Squibb within five years of the effective date of the BMS Agreement. The research term for each collaboration target could be extended in one year increments up to three times.

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 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 continues to collaborate with Bristol Myers Squibb to discover and conduct preclinical development of PROBODY therapeutics against targets selected by Bristol Myers Squibb over the estimated research period, which is projected to end in April 2025. Pursuant to Amendment 2, the Company was eligible to receive contingent payments for development, regulatory and sales milestones. It is also entitled to tiered mid-single to low double-digit percentage of royalties from potential future sales. The Company accounted for Amendment 2 as a modification and reallocated the remaining unrecognized transaction price to the remaining performance obligations.

In October 2022, the Company and Bristol Myers Squibb amended the BMS Agreement and entered into Amendment Number 3 (“Amendment 3”), as previously amended by Amendment 1 and Amendment 2, to clarify the rights and restrictions of certain new proprietary antibodies that the parties exchanged. There were no substantive changes to each party's performance obligations.

In March 2024, following a Bristol Myers Squibb corporate portfolio prioritization process, Bristol Myers Squibb notified CytomX that it does not intend to continue the development of BMS-986288 beyond the current Phase 2 study and terminated its collaboration license to the CTLA-4 target under the collaboration. BMS-986288 was Bristol Myers Squibb’s leading next generation PROBODY CTLA-4 program that it had previously prioritized over BMS-986249, which was a PROBODY version of ipilimumab.

In June 2024, Bristol Myers Squibb prioritized its pre-clinical research activities under the collaboration and revised the research scope by one collaboration target. The Company determined that it has no further obligations related to the target that was deprioritized and accounted for the reduction of the target as a modification and the related remaining unrecognized transaction price was reallocated to the remaining performance obligations. The Company has received in aggregate $297.0 million in upfront and milestone payments under the agreement. The Company's research efforts on all the ongoing programs were completed in April 2025 upon which the $11.6 million of remaining deferred revenue was fully recognized. In May 2025, one collaboration target was also terminated with two months written notice pursuant to the BMS Agreement and two preclinical programs remain in development with Bristol Myers Squibb responsible for further advancement.

ModernaTX, Inc.

The Company and ModernaTX, Inc. (“Moderna”) entered into a Collaboration and License Agreement (the “Moderna Agreement”) on December 30, 2022, the effective date, to collaborate on discovery and preclinical research and development activities to create investigational messenger RNA (“mRNA”) based conditionally activated therapies using the Company’s PROBODY therapeutic technology. Moderna is solely responsible for the development (preclinical and clinical), manufacturing, and commercialization of any products under the Moderna Agreement.

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 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. Due to Moderna's budget considerations in 2025, the Company's remaining activities for its performance obligation are currently paused pending future alignment with Moderna.

As of December 31, 2025 and 2024, deferred revenue relating to the Moderna Agreement was $9.3 million and $9.3 million, respectively. The amount due from Moderna under the Moderna Agreement was $0 and $0.9 million as of December 31, 2025 and December 31, 2024, respectively.

Regeneron Pharmaceuticals, Inc.

The Company and Regeneron Pharmaceuticals Inc. (“Regeneron”) entered into a Collaboration and License Agreement (the “Regeneron Agreement”) on November 16, 2022, to collaborate on creation of conditionally-activated investigational bispecific cancer therapies utilizing the Company’s PROBODY® therapeutic platform and Regeneron’s Veloci-Bi® bispecific antibody development platform. The Company and Regeneron will collaborate on preclinical research and discovery activities for initially agreed upon collaboration programs (“Collaboration Program”) with an option to expand additional Collaboration Programs (“Additional Collaboration Program Option”).

Under the Collaboration and License Agreement, the Company granted Regeneron an exclusive, worldwide, royalty-bearing license under certain Company intellectual property to develop, manufacture, commercialize and otherwise exploit licensed products (“Licensed Products”) for all human and non-human diagnostic, prophylactic and therapeutic uses in oncology. Regeneron is responsible for funding the cost of preclinical research and discovery activities of both parties for all Licensed Products and for funding the cost of development, manufacturing and commercialization of all Licensed Products worldwide.

Pursuant to the Regeneron Agreement, the consideration from Regeneron is comprised of an upfront fee of $30.0 million, contingent payments for development and regulatory milestones and commercial milestone payments of up to an aggregate of approximately $0.8 billion. If Regeneron exercises its Additional Collaboration Program Option, the Company would be eligible to receive additional upfront and milestone payments aggregating up to approximately $1.2 billion. The Company is also entitled to tiered royalties from high-single digit to low-teen percentage royalties from potential future sales. In addition, the Company will receive research and development service fees based on a prescribed FTE rate.

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 each combined performance obligation over the estimated research service period of four years, which is projected to end in November 2026.

As of December 31, 2025 and 2024, deferred revenue relating to the Regeneron Agreement was $10.5 million and $15.6 million, respectively. The amount due from Regeneron under the Regeneron Agreement was $0.8 million and $1.0 million as of December 31, 2025 and December 31, 2024, respectively.

Contract Liabilities

The Company expects that the $28.5 million of deferred revenue related to the following contracts as of December 31, 2025 will be recognized as revenue based on actual FTE effort and estimated program progress as set forth below. However, the timing of revenue recognition could differ from the estimates depending on facts and circumstances impacting the various contracts, including progress of research and development, resources assigned to the contracts by the Company or its collaboration partners or other factors outside of the Company’s control.