Shanghai Junshi Biosciences : VOLUNTARY ANNOUNCEMENT - UPDATE ON PROGRESS FOR RECOMBINANT HUMANIZED ANTI-BTLA MONOCLONAL ANTIBODY INJECTION

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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-

UPDATE ON PROGRESS FOR RECOMBINANT HUMANIZED ANTI-BTLA

MONOCLONAL ANTIBODY INJECTION

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 4 February 2020.

The board (the "Board") of directors (the "Directors") of the Company is pleased to announce that the Company and its subsidiaries Suzhou Junmeng Biosciences Co., Ltd.* (蘇州君盟生物醫藥科技 有限公司), Shanghai Junshi Biotechnology Co., Ltd.* (上海君實生物工程有限公司) and Suzhou Union Biopharm Biosciences Co., Ltd.* (蘇州眾合生物醫藥科技有限公司) have received the

Clinical Trial Approval in respect of the "recombinant humanized anti-BTLA monoclonal antibody injection" (project code: TAB004/JS004) issued by the National Medical Products Administration (the "NMPA"), the relevant information of which is set out as follows:

1. DRUG OVERVIEW

Drug name:	Recombinant humanized anti-BTLA monoclonal antibody injection
Acceptance No.:	CXSL1900129
Applicants:	Shanghai Junshi Biosciences Co., Ltd.*, Suzhou Junmeng Biosciences
	Co., Ltd.* ( 蘇州君盟生物醫藥科技有限公司), Shanghai Junshi
	Biotechnology Co., Ltd.* (上海君實生物工程有限公司) and Suzhou
	Union Biopharm Biosciences Co., Ltd.* (蘇州眾合生物醫藥科技有限
	公司)
Review conclusion:	According to the Drug Administration Law of the People's Republic
	of China and relevant regulations, after the review, the recombinant
	humanized anti-BTLA monoclonal antibody injection accepted for
	application on 6 November 2019 fulfils the relevant requirements
	for drug registration and is approved to conduct clinical trials in
	accordance with the submitted program.

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1. INFORMATION ABOUT DRUG
   TAB004/JS004 is the world's first anti-BTLA monoclonal antibody for cancer treatment approved for clinical trial. It is also the second drug candidate independently developed by the Company that obtained IND approval from the U.S. Food and Drug Administration after toripalimab, of which the Company owns complete independent intellectual property rights. Pre-clinical studies have shown that TAB004/JS004 can promote tumor-specific T cells proliferation, enhance lymphocyte function, reduce tumor burden and increase survival rates in a BTLA humanized mouse tumor model. When combined with toripalimab, TAB004/ JS004 could further enhance the proliferation of tumor-specific T cells and the production of anti-tumor cytokines, offering more options for combination therapy. Currently, there are no products with similar targets on the market.
   In April 2019, the IND of TAB004/JS004 for treatment of patients with advanced unresectable or metastatic solid tumors (including lymphoma) and patients refractory to prior PD-1 antibody treatment was approved by the U.S. Food and Drug Administration for clinical trial. In October 2019, the first patient has been successfully dosed in the Phase I clinical trial
   (NCT04137900) conducted by the Company in the U.S. In November 2019, the Company and its subsidiaries Suzhou Junmeng Biosciences Co., Ltd.* (蘇州君盟生物醫藥科技有限公 司), Shanghai Junshi Biotechnology Co., Ltd.* (上海君實生物工程有限公司) and Suzhou Union Biopharm Biosciences Co., Ltd.* (蘇州眾合生物醫藥科技有限公司) submitted an application for clinical trial to the NMPA and received an acceptance notice.

As at 31 December 2019, the Company has made an investment of approximately RMB63.18 million in the research and development project of the drug.

According to the laws and regulations in relation to drug registration of the PRC, the drug, upon obtaining the Clinical Trial Approval, shall be subject to clinical trial and review and approval from the NMPA before its production and marketing.

1. RISK WARNING
   As pharmaceutical product is characterized by high technology, high risk and high added value, and the long cycles constituted from its preliminary R&D to clinical trial application and approval and to production involve many stages and is susceptible to some uncertainties, the investors are advised to make decision cautiously and pay attention to investment risks. The Company will actively advance the above research and development project according to relevant regulations of the PRC and fulfill its information disclosure obligations in a timely manner in relation to the subsequent progress of the project.

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Cautionary Statement required by Rule 18A.05 of the Listing Rules of the Stock Exchange: We may not be able to ultimately develop and market TAB004/JS004 successfully. Investors are reminded to exercise caution.

By order of the Board

Shanghai Junshi Biosciences Co., Ltd.*

Mr. Xiong Jun

Chairman

Shanghai, the PRC, 4 February 2020

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, Dr. Wu Hai and Dr. Yao Sheng as executive Directors; Mr. Tang Yi, Mr. Li Cong, Mr. Yi Qingqing and Mr. Lin Lijun as non-executive Directors; and Dr. Chen Lieping, Dr. He Jia, Mr. Chen Xinjun, Mr. Qian Zhi and Dr. Roy Steven Herbst as independent non-executive Directors.

• For identification purpose only

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