Chronic Hepatitis B virus is one of the main causes of liver diseases including cirrhosis and hepatocellular carcinoma. Isonicotinic acid inhibitors of the histone lysine demethylase 5 (KDM5) with potent anti-HBV activity. 

GS-5801, a potent inhibitor of KDM5, has antiviral activity against HBV in a primary human hepatocytes infection model, with the cellular permeability, oral bioavailability. GS-5801 was synthesized by Medicilon.

Reference

Sarah A Gilmore, et al. Characterization of a KDM5 small molecule inhibitor with antiviral activity against hepatitis B virus. PLoS One. 2022 Dec 7;17(12):e0271145. doi: 10.1371/journal.pone.0271145.