Ascletis Announces Results of the Phase IIa trial of ASC22 (Envafolimab) in Patients with Chronic Hepatitis B to be Presented in Oral Parallel Session at The Liver Meeting(R) 2021 by American Association for the Study of Liver Diseases

HANGZHOU and SHAOXING,China,Oct. 12,2021 --Ascletis Pharma Inc. (HKEX: 1672) announces today that the results of Phase IIa trial of subcutaneously administered PD-L1 antibody ASC22 (Envafolimab) in patients with chronic hepatitis B (CHB) will be presented in oral parallel session at The Liver Meeting® 2021 by American Association for the Study of Liver Diseases (AASLD). The Liver Meeting® by AASLD is one of the world's premier meetings on liver disease and will be held during Nov.12-15 this year.

"We are excited that the abstract of Phase IIa trial of ASC22 in patients with CHB has been selected for oral presentation at The Liver Meeting®,"said Dr. Jinzi J. Wu,Founder,Chairman and CEO of Ascletis,"We believe that this first-in-class immunotherapy with the positive Phase IIa data and its advantage in safety and convenience has great potential to functionally cure CHB."

The abstract of Ascletis to be presented at The Liver Meeting® 2021 by AASLD is as follow:

A PHASE IIa TRIAL OF SUBCUTANEOUSLY ADMINISTERED PD-L1 ANTIBODY ASC22 (ENVAFOLIMAB) IN PATIENTS WITH CHRONIC HEPATITIS B

Presentation Type: Oral,Parallel Session

Publication Number: 91

Session Title: Parallel 13: Novel HBV Therapies and Approaches

Presenting Author：Prof. Guiqiang Wang,MD,Peking University First Hospital

Session Broadcast Date and Time: Sunday,November 14,2021,10:00 AM-11：30 AM EST

Highlights:

- ASC22 (Envafolimab) is a subcutaneously administered monoclonal antibody against PD-L1 and blockade of PD-1/PD-L1 pathway can restore HBV specific T-cell function which may lead to a functional cure of CHB.

- The Phase IIa clinical trial was a single dose escalation study of three subcutaneously administered doses (0.3,1.0 and 2.5 mg/kg,three patients per dose) with 12-week follow-up to explore the safety and preliminary efficacy of ASC22 in CHB patients that were all on nucleoside analogs treatments.

- The data indicated that there was a trend of dose-dependent HBsAg reduction after single dose administration of 0.3,1.0 or 2.5 mg/kg ASC22 during 12-week follow-up.

- Among three patients receiving 2.5 mg/kg dose,one patient achieved a maximum HBsAg reduction of 1.2 log10 IU/mL during the 12-week follow-up.

- ASC22 is safe and well tolerated at all three dose levels with only grade 1 adverse effects.

About Ascletis

Ascletis is an innovative R&D driven biotech listed on the Hong Kong Stock Exchange (1672.HK). Ascletis is committed to developing and commercializing innovative drugs in the areas of NASH,cancer lipid metabolism and oral checkpoint inhibitors,and viral diseases to address unmet medical needs both in China and globally. Led by a management team with deep expertise and a proven track record,Ascletis has developed into a fully integrated platform covering the entire value chain from discovery and development to manufacturing and commercialization. Ascletis has three marketed products and a robust R&D pipeline of drug candidates.

1. NASH: Gannex,a wholly-owned company of Ascletis,is dedicated to the R&D and commercialization of new drugs in the field of NASH. Gannex has three clinical stage drug candidates against three different targets – FASN,THRβ and FXR,and three fixed-dose combinations. 2. Cancer lipid metabolism and oral checkpoint inhibitors: a pipeline of oral inhibitors targeting FASN,which plays a key role in cancer lipid metabolism,and a pipeline of oral PD-L1 small molecule next generation checkpoint inhibitors. 3. Viral diseases: (1) Hepatitis B: focus on breakthrough therapies for CHB functional cure with a subcutaneously-injected PD-L1 antibody – ASC22 and Pegasys® as cornerstone drugs. (2) Hepatitis C: successfully launched an all-oral regimen of combining ASCLEVIR® and GANOVO® (RDV/DNV regimen). (3) HIV/AIDS: ASC22,an immune therapy to restore HIV-specific immune responses and eventually lead to a functional cure of HIV-infected patients. For more information,please visit www.ascletis.com.