Lomibuvir (VCH-222) is a novel, potent and selective inhibitor of non-nucleoside polymerase of the hepatitis C virus (HCV) RNA-dependent RNA polymerase, with an IC50 range of 0.94-1.2 μM. Lomibuvir was generated from ViroChem's research programme investigating HCV NS5B polymerase inhibitors. In phase 1 and 2 clinical studies, Lomibuvir demonstrated effective antiviral efficacy, with substantial reductions in plasma HCV RNA in patients chronically infected with genotype 1 HCV. On 15 May 2014 Vertex Pharmaceuticals completes a phase II trial in Hepatitis C (treatment-naive, combination therapy) in USA, Canada, Germany, Poland and United Kingdom (NCT01516918). On 26 Jul 2016 Trek Therapeutics acquires lomibuvir from Vertex Pharmaceuticals.