On November 7, 2023, Bastiano Sanna, Ph.D., a current Class III member of the Board of Directors of Adicet Bio, Inc., notified the Company of his resignation from the Board and Audit Committee of the Board (?Audit Committee?), effective as of November 7, 2023. Dr. Sanna?s resignation from the Board was not the result of any disagreement with management or the Board or on any matter relating to the Company?s operations, policies or practices. The Board does not expect to nominate a replacement candidate to replace Dr. Sanna.

Effective as of November 7, 2023, the size of the Board was reduced from nine (9) to eight (8) members. In connection with Dr. Sanna?s resignation, effective as of the Effective Date, the Board appointed Katie Peng as a member of the Audit Committee. The Board has determined that Ms. Peng meets the requirements for independence of audit committee members under the applicable listing standards of the Nasdaq Global Market and the Securities Exchange Act of 1934, as amended.

As of the Effective Date, the Audit Committee is composed of Steve Dubin, serving as chair of the Audit Committee and ?audit committee financial expert? as defined in Item 407(d)(5) of Regulation S-K, Andrew Sinclair, Ph.D., and Ms. Peng.