2​ Biological Activity Danoprevir is a highly potent, orally absorbed inhibitor of the NS3/4A protease for treating chronic HCV infections. This agent is currently in Phase 2b study. [1] In biochemical assays using HCV NS3/4A protease domains derived from genotypes 1b, 1a, 2, or 3, the EC50 value of Danoprevir is <300 pM, 400 pM, 400 pM and 12.4 nM, respectively. Its EC50 value against full-length genotype-1b protease is 900 pM. Danoprevir retains subnanomolar to low-nanomolar potency against the NS3/4A variants at positions A156 and D168 that confer resistance to other experimental NS3/4A inhibitors.[1]Danoprevir is 97.9% bound by human plasma protein, and its replicon potency is shifted modestly by human serum. Danoprevir does not inhibit a panel of selected serine proteases, a broader ligand panel, or hERG ion channel. Its CC50 value is >50 mM. ITMN-191 does not inhibit CYP450 isoforms 1A2, 2C19, 2C9, 2D6 and 3A4 at IC50s > 10 mM in human liver microsomes (HLMs). Use of CYP450 inhibitors show ITMN-191 to be metabolized by multiple CYP450 isoforms. [1] 3​ References: http://www.natap.org/2006/DDW/DDW_30.htm http://www.natap.org/2006/DDW/DDW_30.htm ; The pharmacological and toxicological properties of this product have not been fully investigated. Exercise caution in use and handling. This product must not be used in humans.