CytomX Therapeutics Inc

Trading Arrangements

During the three months ended December 31, 2024, none of our directors or officers (as defined in Rule 16a-1(f) under the Securities Exchange Act of 1934, as amended)adopted, terminated ormodified a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K.

Termination of CX-2009 & CX-2029

On January 31, 2025, the Company sent formal notice of termination to AbbVie Global Enterprises Ltd. (“AbbVie”) regarding the Transition Agreement dated August 22, 2023 between AbbVie and the Company (the “AbbVie Transition Agreement”) and the sublicense pertaining to CX-2029 under the AbbVie Transition Agreement. The Company previously announced in 2023 that it would not significantly invest in further development and has now terminated AbbVie Transition Agreement.

Qn January 31, 2025, the Company sent formal notice of termination to ImmunoGen, Inc. ( “ImmunoGen”, now AbbVie) regarding the License Agreement dated February 16, 2016 between ImmunoGen and the Company (the “ImmunoGen License Agreement”) and the sublicense pertaining to CX-2009 under the Immunogen License Agreement. The Company previously announced it would end development work of CX-2009 in 2022 and has now terminated ImmunoGen License Agreement.

2025 Executive Retention Program

To further incentivize the Company’s executive efforts critical to 2025 goals of the Company, and to recognize their continued commitment to the organization, the Board approved a 2025 cash incentive award program (the “Retention Program”) effective upon filing of the annual report on Form 10-K for the fiscal year 2024. The Retention Program is conditioned on the achievement by the Company of $50 million of new capital from all sources by December 31, 2025, and continued employment by the Company as of the date of completion of the performance condition. Under this Retention Program, Company executives will be eligible to receive a one-time cash payment equal to 50% of annual target bonus incentive of such executive upon the successful completion of this performance condition if employed on such date. No retention awards will be earned or issued if the new capital condition is not met by December 31, 2025. Executives did not earn and the Company did not pay annual cash bonus for 2024.