This potent allosteric inhibitor (FW = 673.87 g/mol) targets hepatitis C virus NS5B polymerase IC50 <0.5 nM (biochemical assay) and EC50 = 0.8-6 nM (replicon assay). Unlike prior cyclopropyl-fused indolobenzazepine inhibitors, BMS-791325 has improved solubility and membrane permeability properties as well as reduced off-target activities, directed most notably against human pregnane X receptor (hPXR) transactivation.