Shanghai Junshi Biosciences : VOLUNTARY ANNOUNCEMENT - UPDATE ON PROGRESS FOR TORIPALIMAB 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 TORIPALIMAB 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 10 September 2020.

The board (the "Board") of directors (the "Directors") of the Company is pleased to announce that Toripalimab Injection for treatment of nasopharyngeal carcinoma has recently received the breakthrough therapy designation (the "Breakthrough Therapy Designation") granted by the U.S. Food and Drug Administration (the "FDA"). Toripalimab Injection is the first domestic anti-PD-1 monoclonal antibody to receive the Breakthrough Therapy Designation granted by the FDA and this is another important registration progress following the grant of the orphan-drug designation by the FDA for the treatment of nasopharyngeal carcinoma with Toripalimab in May 2020.

INFORMATION ABOUT TORIPALIMAB INJECTION

Toripalimab Injection, as the first domestic anti-PD-1 monoclonal antibody that has obtained marketing approval in China, received support from the National Science and Technology Major Project. The clinical investigation and research of Toripalimab Injection has commenced since the beginning of 2016. So far, more than 30 clinical studies covering more than ten indications have been carried out in China, the United States and other countries.

In December 2018, Toripalimab Injection has obtained conditional approval by the National Medical Products Administration (the "NMPA"), and is used to treat locally advanced or metastatic melanoma after failure of routine systemic treatment. In April 2020, the supplemental New Drug Application ("NDA") of Toripalimab Injection for the treatment of new indications of recurrent/ metastatic nasopharyngeal carcinoma after failure of second-line and above systemic treatment has been accepted by the NMPA. The supplemental NDA is the world's first NDA of anti-PD-1 monoclonal antibody for the treatment of recurrent/metastatic nasopharyngeal carcinoma. In addition, JUPITER-02 study (NCT03581786), a Phase III clinical study of Toripalimab Injection combined with chemotherapy as a first-line treatment in patients with recurrent or metastatic nasopharyngeal carcinoma has completed the enrollment. In May 2020, the supplemental NDA of Toripalimab Injection for the treatment of new indications of locally advanced or metastatic urothelial carcinoma after systemic treatment has been accepted by the NMPA.

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In March 2020, Toripalimab in combination with axitinib in the treatment of mucosal melanoma was granted the orphan-drug designation by the FDA. In May 2020, Toripalimab was granted the orphan-drug designation by the FDA in the treatment of nasopharyngeal carcinoma.

THE IMPACT OF THE DESIGNATION ON THE COMPANY

Breakthrough therapy, originated from the provisions of the Food and Drug Administration Safety and Innovation Act (FDASIA), is applicable to drugs that treat serious or life-threatening diseases and whose preliminary clinical evidences show that they are significantly superior to existing therapies. It aims to accelerate the development and evaluation process of the drug. It is another important new drug review path of the FDA after the introduction of fast track, accelerated approval and priority review. According to the regulations, the development process for drugs receiving Breakthrough Therapy Designation will receive more guidance and various support, including those from senior FDA officials, so as to offer new treatment options for patients in the shortest time.

The receipt of the Breakthrough Therapy Designation granted by the FDA by Toripalimab for the treatment of nasopharyngeal carcinoma can greatly support and accelerate the commercial development plan of Toripalimab in the United States. The Company will work closely with the FDA to ensure the efficient implementation of drug development plan.

RISK WARNING

As pharmaceutical products are characterized by high technology, high risks and high added value, and the research and development of the medicine depends on various factors such as technology, review and policies, the assessment and approval policies and the future situation of market competition of the product are subject to risk of uncertainties. It is uncertain whether and when the medicine will successfully enter the United States market. Investors are advised to exercise caution and beware of investment risks when making investment decisions.

By order of the Board

Shanghai Junshi Biosciences Co., Ltd.*

Mr. Xiong Jun

Chairman

Shanghai, the PRC, 10 September 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, Mr. Chen Xinjun, Mr. Qian Zhi, Mr. Zhang Chun and Dr. Roy Steven Herbst as independent non-executive Directors.

• For identification purpose only

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