Shanghai Junshi Biosciences : VOLUNTARY ANNOUNCEMENT - INITIATING ROLLING SUBMISSION OF BIOLOGICS LICENSE APPLICATION FOR TORIPALIMAB WITH FDA FOR THE TREATMENT OF NASOPHARYNGEAL CARCINOMA

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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-

INITIATING ROLLING SUBMISSION OF BIOLOGICS LICENSE

APPLICATION FOR TORIPALIMAB WITH FDA FOR THE TREATMENT OF NASOPHARYNGEAL CARCINOMA

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 3 March 2021.

The board (the "Board") of directors (the "Directors") of the Company is pleased to announce that TopAlliance Biosciences, Inc., a subsidiary of the Company, has initiated the rolling submission of its Biologics License Application ("BLA") for toripalimab (product code: "TAB001/JS001") with the US Food and Drug Administration (the "FDA") for the treatment of recurrent or metastatic nasopharyngeal carcinoma. Relevant information is as follows:

ABOUT TORIPALIMAB

In September 2020, toripalimab was granted Breakthrough Therapy Designation by the FDA for the treatment of recurrent or metastatic nasopharyngeal carcinoma. By virtue of the Breakthrough Therapy Designation, the BLA for toripalimab is able to make a rolling submission and obtain a rolling review by the FDA for the treatment of nasopharyngeal carcinoma. Rolling review refers to when applying for BLA or New Drug Application ("NDA"), pharmaceutical enterprises can submit the application documents to the FDA for review in batches, instead of waiting for the application documents to be completed before submitting an application to the FDA, which can shorten the review cycle of new drugs. Toripalimab has become the first domestic anti-PD-1 monoclonal antibody to submit a BLA to the FDA.

Toripalimab was the first domestic anti-PD-1 monoclonal antibody approved for marketing in China. More than thirty company-sponsored clinical studies covering more than fifteen indications have been conducted globally, including in China and the United States. On 17 December 2018, toripalimab obtained a conditional approval from the National Medical Products Administration (the "NMPA") for the treatment of unresectable or metastatic melanoma after standard therapy failure. Toripalimab was included in the 2019 and 2020 Guidelines of Chinese Society of Clinical Oncology (CSCO) for the Diagnosis and Treatment of Melanoma. In February 2021, toripalimab received a second conditional approval from NMPA for the treatment of patients with recurrent or metastatic nasopharyngeal carcinoma after failure of at least two lines ofprior systemic therapy. The supplemental NDA of toripalimab for the second-line treatment of metastatic urothelial carcinoma was accepted by the NMPA in May 2020 and received priority review designations from the NMPA in July 2020. In December 2020, toripalimab injection was successfully included in the updated National Reimbursement Drug List. In February 2021, the supplemental NDA of toripalimab in combination with chemotherapy for the first-line treatment of patients with advanced, recurrent or metastatic nasopharyngeal carcinoma was accepted by the NMPA. Currently, toripalimab has been granted 1 Breakthrough, 1 Fast Track, and 3 Orphan Drug Designations by the FDA for the treatment of mucosal melanoma, nasopharyngeal carcinoma, and soft tissue sarcoma.

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 described research and development project 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, 3 March 2021

As at the date of this announcement, the Board 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