Shanghai Public Health Clinical Center Completed Patient Enrollment in Clinical Study of PD-L1 Antibody ASC22 (Envafolimab) in Combination with Chidamide for Functional Cure of HIV Infection

HANGZHOU and SHAOXING,China,Sept. 15,2022 --Ascletis Pharma Inc. (HKEX: 1672,"Ascletis") today announces that the clinical study of PD-L1 antibody ASC22 (Envafolimab) in combination with Chidamide for functional cure of human immunodeficiency virus (HIV) infection has completed the enrollment of 15 HIV infected patients.

The objective of this study (ClinicalTrials.gov Identifier: NCT05129189) is to evaluate the efficacy of ASC22 (Envafolimab) combined with Chidamide on the viral reservoirs of latently infected cells in HIV patients. Ascletis BioScience Co.,Ltd. and Shenzhen Chipscreen Biosciences Co.,Ltd. provide ASC22 (Envafolimab) and Chidamide,respectively,for the clinical trial.

The study design of this trial is 1 mg/kg ASC22 (Envafolimab) subcutaneous injection once every four weeks (Q4W) in combination with 10 mg Chidamide administered orally twice a week (BIW) with 12-week treatment.

ASC22 (Envafolimab) is a subcutaneously administered single domain antibody against PD-L1 and has the potential to restore virus-specific immune responses in patients with chronic viral infection such as hepatitis B virus (HBV) and HIV. Latently infected cells by HIV are a major barrier to curing HIV infection. Recent data[1]demonstrated that blocking PD-1/PD-L1 pathway resulted in reversing HIV latency in the clinical trial and supported the rationale for combining PD-1/PD-L1 antibody with other drugs to reduce the HIV reservoir of latently infected cells. Chidamide is the global first approved subtype-selective histone deacetylase oral inhibitor (HDACi) mainly targeting the subtype 1,2,3 of Class I and subtype 10 of Class IIb histone deacetylase (HDAC),with a mechanism against epigenetic abnormality.

"The clinical study of PD-L1 antibody ASC22 (Envafolimab) in combination with Chidamide for functional cure of HIV infection enrolled the first patient on July 1,2022. I'm very happy it completed all patient enrollment within less than 3 months. I expect to advance the clinical study to further explore the potential of ASC22 (Envafolimab) in combination with Chidamide as functional cure of HIV Infection." said Jun Chen,MD,Deputy Chief Physician,Infection and Immunity,Shanghai Public Health Clinical Center and the principal investigator of the study.

"Functional cure of HIV/AIDS remains a challenge in China and globally despite the improved access of standard ART treatment. PD-1 and PD-L1 expressions are elevated in HIV-1 infected patients compared with healthy subjects. Recent data indicated that blocking PD-1/PD-L1 pathway reversed HIV latency in patients,and hopefully clear the HIV reservoir.Previous studies have suggested that PD-1/PD-L1 inhibitors may be very promising drugs for achieving a functional cure for HIV,and I expect the results of the study could benefit more HIV-infected patients." said Dr. Jinzi J. Wu,Founder,Chairman and CEO of Ascletis.

Dr. Lu Xianping,Chairman and General Manager of Chipscreen Biosciences,stated,"The major obstacle that impedes HIV eradication is the persistence of latent reservoir,while current treatments are still ineffective in eliminating HIV reservoir.Data showed Chidamide safely and vigorously disrupts HIV latency,and therefore it is expected to play a key role in treatment. I expect that the results of Chidamide combined with ASC22 will bring more positive benefits to patients with HIV/AIDS."

[1] Uldrick et al.,Sci. Transl. Med. 14,eabl3836 (2022) 26 January 2022

About Ascletis

Ascletis is an innovative R&D driven biotech listed on the Hong Kong Stock Exchange (1672.HK),covering the entire value chain from discovery and development to manufacturing and commercialization. Led by a management team with deep expertise and a proven track record,Ascletis focuses on three therapeutic areas with unmet medical needs from a global perspective: viral diseases,non-alcoholic steatohepatitis (NASH) and oncology. Through excellent execution,Ascletis rapidly advances its drug pipeline with an aim of leading in global competition. To date,Ascletis has three marketed products,i.e. ritonavir tablets,GANOVO® and ASCLEVIR®,and 20 drug candidates in its R&D pipeline. The most advanced drug candidates include ASC22 (CHB functional cure),ASC10 and ASC11 (oral small molecules for COVID-19 treatment),ASC40 (recurrent glioblastoma),ASC42 (PBC,primary biliary cholangitis),and ASC40 (acne).

For more information,please visit www.ascletis.com.