Shanghai Junshi Biosciences : VOLUNTARY ANNOUNCEMENT - XPO1 INHIBITOR JS110 RECEIVED THE CLINICAL TRIAL APPROVAL

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SHANGHAI JUNSHI BIOSCIENCES CO., LTD.*

上海君實生物醫藥科技股份有限公司

(a joint stock company incorporated in the People's Republic of China with limited liability)

(Stock code: 1877)

VOLUNTARY ANNOUNCEMENT -

XPO1 INHIBITOR JS110 RECEIVED THE CLINICAL TRIAL APPROVAL

This announcement is made by Shanghai Junshi Biosciences Co., Ltd.* (上海君實生物醫藥科技 股份有限公司) (the "Company") on a voluntary basis. Reference is also made to the overseas

regulatory announcement of the Company dated 26 April 2021.

The board (the "Board") of directors (the "Directors") of the Company is pleased to announce that, Suzhou Junjing Biomedical Technology Co., Ltd.* (蘇州君境生物醫藥科技有限公司), a

company jointly invested by the Company and Wigen Biomedicine Technology (Shanghai) Co., Ltd., has received the Clinical Trial Approval 《( 藥物臨床試驗批准通知書》) issued by the National

Medical Products Administration. The investigational new drug application for the XPO1 inhibitor WJ01024 tablets (product code: "JS110") has been approved. Relevant information is as follows:

ABOUT JS110

Drug name: WJ01024 tablets

Application matter: Registration of Domestic Production of Pharmaceutical Product

Acceptance No.: CXHL2100107, CXHL2100108

Applicant: Suzhou Junjing Biomedical Technology Co., Ltd.* (蘇州君境生物醫藥科技有限公司)

Review conclusion: According to the Drug Administration Law of the People's Republic of China and relevant regulations, upon review, the WJ01024 tablets accepted for application on 7 February 2021 fulfils the relevant requirements regarding drug registration and is approved to conduct clinical trials for advanced malignancies.

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JS110 is a small molecule inhibitor of the nuclear export protein XPO1, which is clinically intended to treat patients with advanced tumors. According to the results of pre-clinical studies, JS110 specifically blocks the function of XPO1, inhibits the nuclear export of a variety of tumor suppressor proteins including p53, and strengthens the function of tumor suppressor proteins. JS110 inhibits the growth and induces death of a variety of tumor cells in vitro. In animal tumor models, JS110 monotherapy or combination therapy can inhibit the growth of a variety of blood and solid tumors. Due to its unique mechanism of action, the development of JS110 is expected to bring new treatments to patients with advanced tumors.

The Company has the world-wide exclusive production rights, licensed production rights and sales rights for JS110. Further details are set forth in the announcement published by the Company on 16 September 2020.

RISK WARNING

Due to the high-tech,high-risk and high-value-added characteristics of pharmaceutical products, there are substantial risks and uncertainties in the process of drug research, development and commercialization. These many stages make it susceptible to uncertainties and therefore, investors are advised to make cautious decisions and pay careful attention to investment risks. The Company will actively pursue the above research and development projects and fulfil its information disclosure obligations regarding the subsequent progress of the projects in a timely manner and in strict accordance with relevant regulations.

By order of the Board

Shanghai Junshi Biosciences Co., Ltd.*

Mr. Xiong Jun

Chairman

Shanghai, the PRC, 26 April 2021

As at the date of this announcement, the board of directors of the Company comprises Mr. Xiong Jun, Dr. Li Ning, Dr. Feng Hui, Mr. Zhang Zhuobing and Dr. Yao Sheng as executive Directors; Dr. Wu Hai, Mr. Tang Yi, Mr. Li Cong, Mr. Yi Qingqing and Mr. Lin Lijun as non-executive Directors; and Dr. Chen Lieping, Mr. Qian Zhi, Mr. Zhang Chun, Dr. Jiang Hualiang and Dr. Roy Steven Herbst as independent non-executive Directors.

• For identification purpose only

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