Telaprevir was evaluated in combination with pegylated interferon and ribavirin in treatment-naive, genotype 1-infected hepatitis C patients.
In the study, 88% and 79% of patients receiving telaprevir achieved a rapid viral response (RVR) at four weeks. Six of nine patients in one treatment arm who completed 12 weeks of treatment, and who had achieved a RVR as defined by the study protocol, continued to have undetectable levels of the virus 20 weeks after stopping all treatment.
The data demonstrated a high rate of rapid viral response in the telaprevir groups and a low rate of on-treatment viral breakthrough, and suggested that only 12 weeks of telaprevir-based therapy enabled some patients to clear the virus. Vertex Pharmaceuticals is developing telaprevir in collaboration with Tibotec.
Vertex said the information from these trials should allow the company to design optimized durations and regimens for phase III development.