Clinical Studies of PD-L1 Antibody ASC22 for HBV Functional Cure Selected for Inclusion in the "Best of The Liver Meeting's Summary" by AASLD Review Committee

-- Inclusion in the "Best of The Liver Meeting's Summary" is a singular honor and indicates the high level with which the AASLD review committee regards Ascletis' research in CHB

-- In patients with the baseline HBsAg level ≤500 IU/mL,the Phase IIb study demonstrated sustained HBsAg loss in 19% patientsin the treatment group vsno subject achieved HBsAg loss in the placebo group. Both groups had comparable baseline HBsAg levels

HANGZHOU and SHAOXING,China,Nov. 16,2021 -- Ascletis Pharma Inc. (HKEX: 1672) announces today that Phase IIa and IIb clinical studies of PD-L1 antibody ASC22 (Envafolimab) for Hepatitis B Virus (HBV) functional cure have been selected for inclusion in the "Best of The Liver Meeting's summary slide deck in the Viral Hepatitis category" at The Liver Meeting® 2021 of the American Association for the Study of Liver Diseases (AASLD). The presenting author of two clinical studies was informed this honor by AASLD President who indicated "…Inclusion in this slide deck is a singular honor and indicates the high level with which the AASLD review committee regards your research…"

The Phase IIa and IIb studies are focused on chronic hepatitis B (CHB) functional cure using a subcutaneously administered PD-L1 antibody ASC22 (Envafolimab).

The two clinical studies are titled (1) A Phase IIa Trial of Subcutaneously Administered PD-L1 Antibody ASC22 (Envafolimab) in Patients With Chronic Hepatitis B; and (2) HBsAg Loss in Chronic Hepatitis B Patients With Subcutaneous PD-L1 Antibody ASC22 (Envafolimab) Plus Nucleos(t)ide Analogs Treatment: Interim Results From a Phase IIb Clinical Trial.

"It is a great honor that both the Phase IIa and Phase IIb studies have been selected for inclusion in the 'Best of The Liver Meeting's summary',which indicating the high level of our research and significant unmet medical needs of functional cure of CHB as regarded by the AASLD review committee,"said Dr. Jinzi J. Wu,Founder,Chairman and CEO of Ascletis,"ASC22 could be a cornerstone immunotherapy for HBV functional cure."

About Ascletis

Ascletis is an innovative R&D driven biotech listed on the Hong Kong Stock Exchange (1672.HK),a global platform covering the entire value chain from discovery and development to manufacturing and commercialization. Ascletis is committed to developing and commercializing innovative drugs in the areas of viral diseases,NASH/PBC,and cancer (oral cancer metabolic checkpoint and immune checkpoint inhibitors) to address unmet medical needs both in China and globally. Led by a management team with deep expertise and a proven track record,Ascletis targets those therapeutic areas with unmet medical needs from a global perspective,and efficiently advances the developments of pipelines with an aim of leading in global competition. To date,Ascletis has three marketed products and 18 robust R&D pipelines of drug candidates with global competitiveness,and is actively exploring new therapeutic areas.

1. Viral Diseases: (1) Hepatitis B Virus (functional cure): focus on breakthrough therapies for CHB functional cure with a subcutaneously-injected PD-L1 antibody – ASC22 and Pegasys® as cornerstone drugs. (2) HIV/AIDS: ASC22,an immune therapy to restore HIV-specific immune responses and eventually lead to a functional cure of HIV-infected patients. (3) Hepatitis C: successfully launched an all-oral regimen of combining ASCLEVIR® and GANOVO® (RDV/DNV regimen).

2. Non-alcoholic Steatohepatitis/Primary Biliary Cholangitis: 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,three fixed-dose combinations for NASH and one PBC program targeting FXR.

3. Cancer (oral cancer metabolic checkpoint and immune 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 immune checkpoint inhibitors.

4. Exploratory Indications: Acne: Following NASH and recurrent GBM,the third indication for ASC40 has been approved to enter Phase 2 clinical trial.