Shanghai Junshi Biosciences : VOLUNTARY ANNOUNCEMENT - PD-1/TGF-BETA BIFUNCTIONAL FUSION PROTEIN JS201 INJECTION 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 -

PD-1/TGF-β BIFUNCTIONAL FUSION PROTEIN JS201 INJECTION

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 6 May 2021.

The board (the "Board") of directors (the "Directors") of the Company is pleased to announce that, the Company 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 PD-1/TGF-β bifunctional fusion protein JS201 injection (product code: "JS201") has been approved. Relevant information is as follows:

ABOUT JS201 INJECTION

Drug name: JS201 injection

Application matter: Registration of Domestic Production of Pharmaceutical Product

Acceptance No.: CXSL2100068

Applicant: Shanghai Junshi Biosciences Co., Ltd.* (上海君實生物醫藥科技股份有限公司)

Review conclusion: According to the Drug Administration Law of the People's Republic of China and relevant regulations, upon review, the JS201 injection accepted on 22 February 2021 meets the relevant requirements for drug registration and is approved to conduct clinical trials for the treatment of advanced malignancies.

JS201 is a bifunctional fusion protein developed independently by the Company that simultaneously targets PD-1 and TGF-β (transforming growth factor-β). In the tumor microenvironment, PD-1 and TGF-β are usually highly expressed at the same time. TGF-β serves an important role in cancer progression by suppressing immune response, which leads to resistance against anti-PD-1 monoclonal antibodies. The blocking of PD-1 and TGF-β immunosuppressive signals, therefore, results in optimal anti-tumor immune responses in select solid tumors where both inhibitory mechanisms are active. JS201 effectively blocks the PD-1/PD-L1 and TGF-β immunosuppressive pathways and improves the immune regulation in the tumor microenvironment, thus stimulating the human immune system to kill tumor cells, effectively enhancing the immune response, and reducing immune escape and drug resistance. As of the date of this announcement, there is no product of a similar target approved for marketing domestically and overseas.

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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 fulfill its information disclosure obligations in a timely manner for subsequent progress in strict accordance with relevant regulations.

By order of the Board

Shanghai Junshi Biosciences Co., Ltd.*

Mr. Xiong Jun

Chairman

Shanghai, the PRC, 6 May 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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