Ascletis Announces IND Approval of Viral Polymerase Inhibitor ASC10 for Monkeypox Indication by U.S. FDA

--Based on available data, ASC10 at the dosage of 800 mg twice daily was approved by the U.S. Food and Drug Administration (FDA) to conduct a Phase Ib study in patients with monkeypox virus disease

--Preclinical studies show that ASC10-A, active metabolite of double prodrug ASC10, has potent antiviral activities against both monkeypox and SARS-CoV-2 viruses

Hangzhou and Shaoxing, China, November 16, 2022--Ascletis Pharma Inc. (HKEX: 1672, “Ascletis”) announces that the U.S. Food and Drug Administration (FDA) has approved the Investigational New Drug (IND) application of ASC10 for monkeypox indication. Based on available data, 800 mg ASC10 twice daily was approved by U.S. FDA to conduct a Phase Ib, randomized, double blind, placebo-controlled study to evaluate safety, tolerability, efficacy and pharmacokinetics of ASC10 tablets in patients with monkeypox virus disease.

ASC10 is an oral double prodrug. After oral administration, both ASC10 and single prodrug molnupiravir are rapidly and completely converted in vivo into the same active metabolite ASC10-A, also known as β-D-N4-hydroxycytidine (NHC) or EIDD-1931.

Preclinical studies show that ASC10-A has broad spectrum antiviral activities including potent activities against both monkeypox and SARS-CoV-2 viruses. Ascletis has filed multiple patent applications globally for ASC10 and its use in viral diseases including monkeypox virus infection.

Monkeypox virus is an orthopoxvirus that causes a disease with symptoms similar to smallpox [1]. As of November 15, 2022, over 79,000[2] confirmed cases have been reported globally and monkeypox virus has spread in 110 countries [2] according to data from World Health Organization (WHO). In particular, a total of 28,947 [3] confirmed monkeypox cases have been reported in the U.S. WHO assesses the risk of monkeypox virus in the Region of the Americas as high [2]

Data from in vitro antiviral cellular assay with infectious monkeypox virus, a study sponsored by Ascletis and conducted at IIT Research Institute (IITRI) of Illinois Institute of Technology in Chicago, U.S, showed that ASC10-A has potent antiviral activity against monkeypox virus, suggesting that ASC10 has the potential to be an effective treatment of monkeypox virus infection. Researchers from National Institute of Infectious Diseases, Tokyo, Japan, tested 132 drugs and the results showed that molnupiravir (active metabolite ASC10-A) and other two drugs have potent cellular antiviral activity in the infectious monkeypox virus assay [4]. The rest of 129 drugs such as remdesivir, favipiravir, sofosbuvir and ribavirin, etc. do not have antiviral activities against monkeypox virus [4].

“It is urgently needed to develop a safe, effective and affordable solution for monkeypox as there is no approved treatment in the world. This IND approval of ASC10 for monkeypox from U.S. FDA further validates Ascletis' in-house R&D capabilities on viral diseases, and it will accelerate our efforts to better address the global challenge imposed by the widespread monkeypox.” said Dr. Jinzi J. Wu, Founder, Chairman and CEO of Ascletis.




[4] Daisuke Akazawa, Hirofumi Ohashi, Takayuki Hishiki, et al. Potential anti-monkeypox virus activity of atovaquone, mefloquine, and molnupiravir, and their potential use as treatments. bioRxiv preprint.

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 (HBV functional cure), ASC10 and ASC11(oral small molecules for COVID-19 treatment), ASC40 (recurrent glioblastoma), ASC42 (PBC, primary biliary cholangitis), and ASC40 (acne).

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