CStone Pharmaceuticals — Director's Dealing 2023

Jun 26, 2023

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CStone Pharmaceuticals 基石藥業

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 2616)

VOLUNTARY ANNOUNCEMENT

FURTHER INCREASE IN SHAREHOLDING BY CEO AND EXECUTIVE DIRECTOR DR. JIANXIN YANG BY 460,000 SHARES, WITH ACCUMULATED PURCHASE TOTALLING 3,732,500 SHARES

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 shareholding in the Company (the “ Shares ”) by Dr. Jianxin Yang (“ Dr. Yang ”), the chief executive officer (the “ CEO ”) and an executive director of the Company.

The Company was informed by Dr. Yang that he has purchased a total of 460,000 Shares in the open market with his own funds on June 19 and June 20, 2023, respectively (the “ Share Purchases ”). Following the Share Purchases, Dr. Yang’s total shareholding interest in the Company was approximately 3.58% of the total issued share capital of the Company as at the date of this announcement. Since assuming the role as CEO in August 2022, Dr. Yang has purchased a total of 3,732,500 shares in the open market with his own funds with a purchase price range of HKD2.55 to HKD4.60.

Dr. Yang informed the Company that he is confident with the Company’s outlook, and the increase in his shareholding in the Company represents his belief in the Company’s ability to maintain steady operations and to achieve rapid growth in a complex and volatile market environment, and the Share Purchases 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 CEO and executive director signifies Dr. Yang’s 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 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 ten new drugs application approvals for its four drugs. Multiple late-stage drug candidates are now under pivotal clinical trials or registration. CStone’s vision is to bring 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, June 26, 2023

As at the date of this announcement, the board of Directors comprises Dr. Wei Li as Chairman and nonexecutive director, Dr. Jianxin Yang as executive director, Mr. Kenneth Walton Hitchner III, 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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