China-based Youcare Pharmaceutical Group (SHA: 688658) has received ethical approval from the China-Japan Friendship Hospital to conduct a Phase II/III study assessing the efficacy and safety of its YKYYO17 aerosol inhalation agent as a potential treatment for mild-to-moderate COVID-19. The drug candidate is a broad-spectrum coronavirus membrane fusion inhibitor polypeptide molecule.
Co-Development and Mechanism of Action
The Category 1 drug candidate, co-developed by the Institute of Medical Biology affiliated with the Chinese Academy of Medical Sciences, exhibits antiviral properties by inhibiting two membrane fusion pathways of cell surface and endosome. YKYYO17 is a lipopeptide compound composed of 43 amino acids. It interacts with the heptapeptide repeat region 1 (HR1) of the S2 subunit of the S protein of COVID-19 to form a heterologous six helix bundle (6 HB), thereby inhibiting the formation of homologous 6 HB between the HR1 and HR2 domains of the virus, blocking the fusion process between the virus and the host cell, and achieving the antiviral purpose.
Broad-Spectrum Antiviral Activity and Clinical Progress
Non-clinical pharmacodynamics studies show that YKYYO17 has a significant inhibitory effect on the original novel coronavirus strain and its multiple epidemic variants, including Delta, Omicron BA. 1, Omicron BA. 2, Omicron BA. 4, Omicron BF. 7, and Omicron XBB, and is not affected by virus variation. Additionally, YKYYO17 demonstrates significant inhibitory effects on other coronaviruses that can cause colds, such as HCoV-NL63 and HCoV-229E, as well as severe acute respiratory syndrome coronavirus (SARS-CoV), Middle Eastern respiratory syndrome coronavirus (MERS-CoV), bat derived coronavirus (batRaTG13), and pangolin derived coronavirus (PCoV GD, PCoV GX), reflecting its broad-spectrum antiviral activity.
YKYY017, which has been approved for clinical trials in China, the US, and Australia, has completed its Phase I study in China, with preliminary data indicating a good tolerability and safety profile, alongside robust in vivo pharmacokinetic data.-Fineline Info & Tech
