CStone Pharmaceuticals — Director's Dealing 2022

Sep 19, 2022

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CStone Pharmaceuticals 基石藥業

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 2616)

VOLUNTARY ANNOUNCEMENT INCREASE IN SHAREHOLDING OF THE COMPANY BY THE CHIEF EXECUTIVE OFFICER AND EXECUTIVE DIRECTOR

This announcement is made by CStone Pharmaceuticals (the “ Company ” or “ CStone ” and together with its subsidiaries, the “ Group ”) on a voluntary basis to inform its shareholders and potential investors in relation to the increase in the holding of shares in the Company (the “ Shares ”) by Dr. Jianxin Yang (“ Dr. Yang ”), the chief executive officer and an executive director of the Company.

The Company was informed by Dr. Yang that he purchased a total of 1,000,000 Shares in the open market with his own fund on September 2, September 7, September 15 and September 16, 2022, respectively. Following the aforesaid purchase of Shares by Dr. Yang, his shareholding interest in the Company has increased to approximately 3.95% of the total issued share capital of the Company as at the date of this announcement.

Dr. Yang informed the Company that he is confident with the Company’s future outlook, and the increase of his shareholding in the Company represents his belief in Company’s ability to continually maintain steady operations and achieve rapid growth in a complex and volatile market environment and demonstrates his unfailing support towards the growth and development of the Company. Dr. Yang does not rule out the possibility of further increasing his shareholding in the Company as and when appropriate.

The board of directors of the Company (the “ Board ”) is of the view that the increase in shareholding of the Company by its chief executive officer and executive director signifies his long-term commitment to, and confidence towards, the future business prospects of the Company.

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About CStone

CStone is a biopharmaceutical company focused on research, development, and commercialization of innovative immuno-oncology and precision medicines to address the unmet medical needs of cancer patients in China and worldwide. Established in 2015, CStone has assembled a world-class management team with extensive experience in innovative drug development, clinical research, and commercialization. The Company has built an oncology-focused pipeline of 15 drug candidates with a strategic emphasis on immuno-oncology combination therapies. Currently, CStone has received nine NDA approvals for its four drugs. Multiple late-stage drug candidates are now under pivotal clinical trials or registration. CStone’s vision is to become globally recognized as a worldrenowned biopharmaceutical company by bringing innovative oncology therapies to cancer patients worldwide.

For more information about CStone, please visit: www.cstonepharma.com.

By Order of the Board CStone Pharmaceuticals Dr. Wei Li Chairman

Suzhou, the People’s Republic of China, September 19, 2022

As at the date of this announcement, the board of directors of the Company comprises Dr. Wei Li as Chairman and non-executive director, Dr. Jianxin Yang as executive director, Mr. Kenneth Walton Hitchner III, Mr. Yanling Cao, Mr. Xianghong Lin and Mr. Edward Hu as non-executive directors, and Dr. Paul Herbert Chew, Mr. Ting Yuk Anthony Wu and Mr. Hongbin Sun as independent non-executive directors.

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