Novartis' investigational oral agent alisporivir cured almost 50% more previously untreated patients with the most common form of hepatitis C when added to a standard treatment regimen, as reported in phase II data presented at the European Association for the Study of the Liver congress in Berlin.

The ESSENTIAL study involved 300 previously untreated patients infected with genotype 1 HCV. Of those treated with alisporivir, plus standard of care (pegylated-interferon alfa 2a/ribavirin), 76% achieved superior viral cure compared to 55% of patients on standard care alone 24 weeks after stopping treatment.

An international phase III study is now underway to evaluate the efficacy and safety of alisporivir combined with standard care in previously untreated HCV G1 patients. The phase II study showed that serious adverse events occurred in 6.9% of patients treated with alispirovir and standard care compared to 5.5% of patients treated with standard care alone. A higher rate of bilirubin (32.9% versus 1.4% in the alisporivir-treated group compared to standard care alone); however, this was transient and reversible and associated with the initial loading dose.