Ascletis Announces Dosing of 4 Healthy Subjects of the First Cohort in Multiple-Dose Escalation Phase I Clinical Trial of Oral 3CLpro Inhibitor ASC11 for COVID-19

--The multiple-dose escalation Phase I clinical trial is expected to enroll 72 healthy subjects,and the enrollment is expected to be completed in the first quarter of 2023

--Ascletis has filed global patent applications for ASC11 and related compounds and their use in viral disease

HANGZHOU and SHAOXING,China,Jan. 16,2023 -- Ascletis Pharma Inc. (HKEX: 1672,"Ascletis") today announces dosing of 4 healthy subjects of the first cohort in multiple-dose escalation Phase I clinical trial of oral 3-chymotrypsin like protease (3CLpro) inhibitor ASC11 in combination with 100 mg ritonavir tablets for COVID-19.

The Phase I clinical trial is expected to enroll 72 healthy subjects,including 60 subjects in single-dose escalation cohorts and multiple-dose escalation cohorts,and 12 subjects in food effect trial. The enrollment is expected to be completed in the first quarter of 2023. Among the aforementioned 60 subjects,32 subjects will be randomized into 4 cohorts to receive escalated multiple doses of ASC11 (in combination with or without 100 mg ritonavir tablets) or matching placebo twice daily (BID) for 5.5 days. The clinical trial is a randomized,double-blind and placebo-controlled study to evaluate the safety,tolerability,and pharmacokinetics (PK) of ASC11 in combination with 100 mg ritonavir tablets in healthy subjects. The aforementioned 12 subjects in the food effect trial will be randomized to receive ASC11 in combination with ritonavir tablets twice (fed or fasted) to evaluate the food effect on PK of ASC11 in combination with ritonavir tablets in healthy subjects.

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.

"We are excited that our COVID-19 drug candidates,ASC10 (RdRp inhibitor) and ASC11 (3CLpro inhibitor),which are discovered and developed in-house and with global patents,both have entered into clinical development,which again marks a great recognition to our in-house R&D capabilities in viral diseases. As COVID-19 pandemic causes persistent huge social and economic implications globally,Ascletis will accelerate our clinical development to fight against the pandemic in China and other countries." 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.