On January 30, 2023, Adam S. Crystal, M.D., Ph.D., informed the company of his intent to resign from his position as the Chief Medical Officer of C4 Therapeutics, Inc., effective as of February 24, 2023, to pursue an opportunity as a head of research and development. After February 24, 2023, Dr. Crystal will cease to be employed by the Company and cease to serve in the role of Chief Medical Officer. In order to provide for the orderly transition of his responsibilities, Dr. Crystal has agreed to provide transitional services after his departure on an as needed basis until September 1, 2023 under the terms of a consulting agreement.

In connection with Dr. Crystal's upcoming departure, the Company has engaged Hagop Youssoufian, M.D. as a clinical development consultant and, upon Dr. Crystal's departure, as the Company's interim Chief Medical Officer. In this role, Dr. Youssoufian will provide advisory and other services to support the Company's operations while the Company completes an ongoing search for a permanent Chief Medical Officer.