Ascletis Announces IND Approval of Oral Viral Polymerase Inhibitor ASC10 for Monkeypox Indication by China NMPA

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

--Ascletis has received the Notice of Issuance from the United States Patent and Trademark Office (USPTO) for the patent application of ASC10 and its derivatives, and their uses to treat multiple virus infections

Hangzhou and Shaoxing, China, January 26, 2023--Ascletis Pharma Inc. (HKEX: 1672, “Ascletis”) announces that the China National Medical Products Administration (NMPA) has approved the Investigational New Drug (IND) application of ASC10 for monkeypox indication.

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 received the Notice of Issuance from the United States Patent and Trademark Office (USPTO) for the patent application of ASC10 and its derivatives, and their uses to treat multiple virus infections including SARS-CoV-2, monkeypox virus and respiratory syncytial virus (RSV). Ascletis is the first Chinese biotech company which has been granted a patent by the USPTO for its in-house developed oral viral polymerase inhibitor and its derivatives.

Monkeypox virus is an orthopoxvirus that causes a disease with symptoms similar to smallpox[1]. As of January 25, 2023, over 85,106[2] confirmed cases have been reported globally and monkeypox virus has spread in 110 countries[2] according to data from World Health Organization (WHO).

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. In August 2022, 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[3]. The rest of 129 drugs such as remdesivir, favipiravir, sofosbuvir and ribavirin, etc. do not have antiviral activities against monkeypox virus[3].

“I'm very glad that the IND application of ASC10 for monkeypox bas been approved by China NMPA, which further validates Ascletis’ in-house R&D capabilities on viral diseases. Currently, there is no approved treatment for monkeypox in the world. We hope that ASC10 will make a contribution to the control of monkeypox globally.” said Dr. Jinzi J. Wu, Founder, Chairman and CEO of Ascletis.



[3] 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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