SinoMab BioScience Limited — Board/Management Information 2025

Jun 6, 2025

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SINOMAB

SinoMab BioScience Limited

中國抗體製藥有限公司

(Incorporated in Hong Kong with limited liability)

(Stock code: 3681)

VOLUNTARY ANNOUNCEMENT CESSATION TO ACT AS PRESIDENT (CHINA)

This announcement is made by SinoMab BioScience Limited (the "Company", together with its subsidiaries, the "Group") on a voluntary basis. The board of directors of the Company (the "Board") hereby announces that with effect from 6 June 2025, Mr. Shanchun WANG ceases to act as the President (PRC) of the Group. The cessation of Mr. Wang to act as the President (PRC) of the Group will not have any material adverse effect on the Group's operations and external partnerships.

By Order of the Board

SinoMab BioScience Limited

Dr. Shui On LEUNG

Executive Director, Chairman and Chief Executive Officer

Hong Kong, 6 June 2025

As at the date of this announcement, the executive directors of the Company are Dr. Shui On LEUNG and Mr. Shanchun WANG, the non-executive directors of the Company are Dr. Haigang CHEN, Mr. Xun DONG, Ms. Xiaosu WANG and Dr. Jianmin ZHANG and the independent non-executive directors of the Company are Mr. George William Hunter CAUTHERLEY, Mr. Ping Cho Terence HON, Dr. Chi Ming LEE and Mr. Dylan Carlo TINKER.