3SBio : VOLUNTARY ANNOUNCEMENT - ACCEPTANCE OF THE IND APPLICATION FOR BEVACIZUMAB BIOSIMILAR IN MAINLAND CHINA

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(Incorporated in the Cayman Islands with limited liability)

(Stock code: 1530)

VOLUNTARY ANNOUNCEMENT

ACCEPTANCE OF THE IND APPLICATION

FOR BEVACIZUMAB BIOSIMILAR IN MAINLAND CHINA

3SBio Inc. (the "Company", together with its subsidiaries, the "Group") wishes to inform the shareholders of the Company of the attached press release in respect of the acceptance of the IND application for bevacizumab biosimilar SB8 ("SB8") by NPMA in China.

This is a voluntary announcement made by the Company. The Group cannot guarantee that SB8 will be successfully or eventually launched in Mainland China. Shareholders and potential investors of the Company are advised to exercise caution when dealing in the shares of the Company.

By order of the Board

3SBio Inc.

Dr. LOU Jing

Chairman

Shenyang, the PRC

14 September 2020

As at the date of this announcement, the directors of the Company are Dr. LOU Jing and Ms. SU Dongmei as executive directors; Mr. HUANG Bin and Mr. TANG Ke as non-executive directors; and Mr. PU Tianruo, Mr. David Ross PARKINSON and Dr. WONG Lap Yan as independent non-executive directors.

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Press release

3SBio Announces Acceptance of the IND Application

for Bevacizumab Biosimilar in Mainland China

(Shenyang, China, September 14, 2020) Chinese leading biopharmaceutical company, 3SBio Inc. (01530.HK), announced today that the China National Medical Products Administration has accepted its IND application for SB8 (the Company's development code: 615), a bevacizumab biosimilar. According to the collaboration agreement between 3SBio Inc. and Samsung Bioepis as announced on January 7, 2019, Sunshine Guojian will be responsible for the clinical development and commercialization of SB8 in Mainland China (excluding Hong Kong, Macao and Taiwan). Marketing authorization for SB8 was granted by the European Union on August 19, 2020, for multiple cancer treatment, including metastatic colorectal cancer, metastatic breast cancer, non- small cell lung cancer, advanced/metastatic renal cell cancer, epithelial ovarian cancer, fallopian tube cancer, primary peritoneal cancer, and cervical cancer.

The Phase III clinical study results of SB8 had been presented at the 2019 European Society of Medical Oncology (ESMO) Congress. The study was a randomized, double-blind,multi-center study, which compared the efficacy, safety, pharmacokinetics, and immunogenicity of SB8 and Avastin in 763 patients with metastatic or relapsed non-squamousnon-small cell lung cancer (NSCLC). The data showed that SB8 has no clinically meaningful differences from Avastin in terms of efficacy, safety, pharmacokinetics and immunogenicity.

It is understood that the indications of bevacizumab biosimilar in China will focus on metastatic colorectal cancer and non-small cell lung cancer. According to the data from the Chinese National Cancer Center, there were 376,000 new cases and 191,000 cases of deaths in relation to colorectal cancer in China in 2015, with an incidence rate of 26.6/100,000 and a mortality rate of 13.5/100,000. The incidence rate of colorectal cancer has increased significantly and the incidence rate in urban areas is significantly higher than that of rural areas. Most of the patients are already in the middle or advanced stage when they are diagnosed. Lung cancer has the highest incidence rate (51.9/100,000) and mortality rate (43.2/100,000) among cancers in China, for instance, there were 733,000 new cases and 610,000 cases of deaths in relation to lung cancer in 2015. More than 85% of lung cancer cases are NSCLC. According to Frost & Sullivan report, the sales revenue of bevacizumab biosimilars in Chinese market is expected to grow at a compound annual growth rate of 343.5% from 2019. Its market size in 2023 will be approximately RMB6.4 billion and the market size of bevacizumab biosimilars in Chinese market will reach RMB9.9 billion by 2030.

"3SBio looks forward to accelerating the clinical development of SB8 in China and to broadening 3Bio's product portfolio in the field of oncology," said Dr. Jing Lou, Chairman of 3SBio. "3SBio will continue to strengthen its leadering position in the field of biopharmaceuticals through internal R&D initiatives and strategic collaborations to introduce more high quality products of urgent demands to both the China and international markets at a higher pace."

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About 3SBio Inc.

3SBio is a fully-integrated biotechnology company in China with market-leading biopharmaceutical franchises in oncology, auto-immune diseases, nephrology, metabolic diseases and dermatology. 3SBio is focusing on building an innovative product pipeline, currently with 22 out of over 30 product candidates under development as National New Drugs. 3SBio's manufacturing capabilities include recombinant proteins, monoclonal antibodies and chemically-synthesized molecules, with production centers in Shenyang, Shanghai, Hangzhou, Shenzhen and Cuomo, Italy. Please visit www.3sbio.com for additional information.

About Bevacizumab

Bevacizumab is a recombinant humanized monoclonal antibody and it became the first clinically used angiogenesis inhibitor in 2004. Its emergence was based on the discovery of human vascular endothelial growth factor (VEGF), a protein that stimulated the growth of blood vessels. Bevacizumab obtained its first approval in the United States in 2004, being used for combination therapy with standard chemotherapy for metastatic colorectal cancer (mCRC). Since then, bevacizumab has been approved for use in certain lung cancers, renal cancers, ovarian cancers, etc. In 1Q2010, bevacizumab was approved for treatment of mCRC in China. As of January 2016, the drug was approved and launched in China for Non-Small Cell Lung Cancer (NSCLC).

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