--The objective of Phase I clinical trial is to identify a safe and efficacious dose for the pivotal Phase II/III in COVID-19 patients. Phase I clinical trial is expected to be completed within the first quarter of 2023

--Phase I clinical trial will also determine if ASC11 needs to be boosted by ritonavir or not

--In antiviral cellular assays, antiviral potency (EC₉₀) of ASC11 is 31-fold of that of Nirmatrelvir, 120-fold of that of S-217622, 16-fold of that of PBI-0451 and 7-fold of that of EDP-235

HANGZHOU and SHAOXING, China, Dec. 7, 2022 /PRNewswire/ -- Ascletis Pharma Inc. (HKEX: 1672, "Ascletis") today announces that China National Medical Products Administration (NMPA) has approved the Investigational New Drug (IND) application for ASC11, an oral inhibitor drug candidate targeting 3-chymotrypsin like protease (3CLpro) for COVID-19.

The objective of Phase I clinical trial is to identify a safe and efficacious dose for the pivotal Phase II/III in COVID-19 patients. Phase I clinical trial is expected to be completed within the first quarter of 2023. Furthermore, Phase I clinical trial will determine if ASC11 needs to be boosted by ritonavir or not. In antiviral cellular assays with infectious SARS-CoV-2, ASC11 demonstrated much higher potency against SARS-CoV-2 than other 3CLpro inhibitors including Nirmatrelvir, S-217622, PBI-0451 and EDP-235. ASC11 remains potent antiviral activity against various popular Omicron variants such as BA.1 and BA.5. In the animal model with infectious SARS-CoV-2, ASC11 also showed potent antiviral activity.

ASC11 is an in-house discovered oral small molecule drug candidate using various proprietary technologies including molecular docking. Ascletis has filed global patent applications for ASC11 and related compounds and their use in viral disease.

"The IND approvals of ASC11 from both China NMPA and U.S. FDA mark a great recognition to our in-house R&D capabilities. We will continue to advance the clinical development of our proprietary COVID-19 pipeline including ASC10 (RdRp inhibitor) and ASC11 (3CLpro inhibitor)." said Dr. Jinzi J. Wu, Founder, Chairman and CEO of Ascletis.

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 22 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.