Shanghai Junshi Biosciences : VOLUNTARY ANNOUNCEMENT - PD-1/TGF-BETA BIFUNCTIONAL FUSION PROTEIN JS201 INJECTION RECEIVED THE ACCEPTANCE NOTICE FOR THE INVESTIGATIONAL NEW DRUG APPLICATION

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SHANGHAI JUNSHI BIOSCIENCES CO., LTD.*

ɪऎёྼ͛يᔼᖹ߅Ҧٰ΅Ϟࠢʮ̡

(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 ACCEPTANCE NOTICE FOR

THE INVESTIGATIONAL NEW DRUG APPLICATION

This announcement is made by Shanghai Junshi Biosciences Co., Ltd.* (ɪऎёྼ͛يᔼᖹ߅Ҧ ٰ΅Ϟࠢʮ̡) (the "Company") on a voluntary basis. Reference is also made to the overseas regulatory announcement of the Company dated 24 February 2021.

The board (the "Board") of directors (the "Directors") of the Company is pleased to announce that, the Company has received the Acceptance Notice ( աଣஷࣣٝ') 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 accepted. 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.* (ɪऎёྼ͛يᔼᖹ߅Ҧٰ΅Ϟࠢʮ̡) Review conclusion: Accepted upon review according to the requirements of Article 32 of the Administrative Licensing Law of the People's Republic of China.

JS201 is a bifunctional fusion protein developed independently by the Company that simultaneously targets PD-1 and TGF-β (transforming growth factor-β). PD-1 and TGF-β usually show high expression at the same time in the tumor microenvironment. TGF-β is an important growth factor in immunosuppression, which in turn mediates the primary resistance of anti-PD-1 monoclonal antibody, thus blocking the two immunosuppressive signals simultaneously, i.e. PD-1 and TGF-β to play a synergistic antitumor effect. JS201 effectively blocks the PD-1/PD-L1 and TGF-β immunosuppressive pathways and improves the immune regulation in the tumor microenvironment, and therefore stimulates the killing effect of the human immune system on tumor cells, effectively enhances the immune response, and reduces 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.

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, 24 February 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 nonexecutive 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