Chinese leading biopharmaceutical company, 3SBio Inc., announced that Selecta Biosciences, Inc., the Company's partner, has commenced the phase III clinical program of a combination therapy involving SEL-212 for the treatment of chronic refractory gout on behalf of SobiTM, and has made a milestone payment of USD 4 million to 3SBio Inc. The Phase III clinical program, known as DISSOLVE, dosed the first patient in September 2020. In 2014, Selecta was authorized by 3SBio Inc. to use pegsiticase, also known as pegadricase, (a recombinant enzyme that metabolizes uric acid) in the development of SEL-212, and it was agreed that 3SBio Inc. would receive milestone payment and royalties in the clinical and future commercialization stages of the product. SEL-212 consists of pegsiticase and ImmTOR? immune tolerance platform, which can durably control serum uric acid, reduce immunogenicity, and allow for repeated monthly dosing.

On 29 July 2020, Sobi and Selecta announced that the companies have entered into a strategic licensing agreement for Selecta's product candidate, SEL-212. Under the agreement, Sobi is responsible for development, regulatory and commercial activities in all markets outside of Greater China(including Mainland China, Hong Kong, S.A.R., China, Macau, S.A.R., China and Taiwan, China), while Selecta will commence phase III research on behalf of Sobi.

Gout is an autoinflammatory disease, of which patients suffer from intensely painful flares and debilitating inflammatory arthritis due to pro-inflammatory monosodium urate (MSU) crystal deposition. High tissue MSU burden is always found in patients with chronic refractory gout, which can lead to frequent gout flares and chronic arthritis. Gout is the most common form of inflammatory arthritis in the United States.

SEL-212 has the potential to reduce serum uric acid and MSU deposits in patients with chronic refractory gout. Recombinant uricases are highly immunogenic in humans, and SEL-212, through Selecta's proprietary ImmTOR platform, has the potential to mitigate the formation of anti-drug antibodies, thereby enabling convenient once-monthly dosing and improving the efficacy and tolerability of the uricase.

"We are greatly inspired by the new progress achieved in the clinical studies of SEL-212. 3SBio has long been focusing on therapeutic areas of major diseases such as auto-immune diseases and tumors, with an aim to develop biologics to address urgent needs. We look forward to advancing our cooperation with Selecta in the future to provide more treatment options for Chinese and global patients," said Dr. Jing Lou, Chairman of 3SBio.

About 3SBio

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 over 30 product candidates underdevelopment, 22 of which are being developed as national new drugs in China. 3SBio's manufacturing capabilities include recombinant proteins, monoclonal antibodies and chemically-synthesized molecules. 3SBio has research and production centers in Shenyang, Shanghai, Hangzhou, Shenzhen and Como, Italy.