In total, around 200million people are thought to be infected hepatitis C virus (HCV). The current standard of care treatment for (HCV) infection is a combination of pegylated interferon, an immune modulator, and ribavirin, an antiviral drug. Interferon/ribavirin therapy is effective in only around 50% of patients with the most difficult-to-treat HCV, type 1. A number of new small molecule antiviral drugs are being developed, and Roche, Pharmasset and InterMune have recently announced the first clinical trial of an interferon-free combination of an HCV NS3/4A protease inhibitor, R7227, and an HCV NS5B polymerase inhibitor prodrug, R7128. Both the protease and polymerase are essential for viral replication and the new study, which will be carried out in Australia and New Zealand, will look at safety and combined antiviral activity of the two compounds in combination.
R7227, which is being developed in collaboration with InterMune, and R7128, which is being developed in collaboration with Pharmasset, have both already successfully completed studies in combination with pegylated interferon and ribavirin.