According to results of an intent-to-treat (ITT) analysis announced by Vertex Pharmaceuticals, more than 80% of hepatitis C patients in each arm of the phase 2 Study C208 achieved a sustained viral response (SVR) with a telaprevir-based regimen.
Telaprevir is a hepatitis C virus (HCV) protease inhibitor being developed by Vertex in collaboration with Tibotec and Mitsubishi Tanabe Pharma.
In the phase II study, which enrolled 161 treatment-naive genotype 1 patients, rates of SVR ranged from 81 to 85% in patients treated with the every 8 hour telaprevir-based regimen, and 82 to 83% in patients treated with the every 12 hour regimen. Adverse events (AEs) were similar to those observed in other trials with telaprevir and were mainly haematologic (anaemia) and cutaneous (rash and pruritus) in nature.
For the vast majority of patients, these high SVR rates were obtained with only 24 weeks of total treatment (half the duration of current standard of care). Total duration of treatment was decided using a criteria based on treatment response. Subjects who achieved undetectable HCV RNA at week 4 (rapid virologic response or RVR) and maintained this through week 20, were allowed to stop all treatment at week 24. Only 18% of subjects were required to continue standard treatment up to week 48.
Patrick Marcellin, professor at Hopital Beaujon, said: “The data presented show that a significant number of treatment-naïve genotype 1 HCV patients achieved sustained virologic response with telaprevir, in combination with standard of care. Telaprevir, which directly targets the virus by aiming to block its replication, could allow shortening treatment duration and increasing cure rates in people with HCV, [compared to standard of care] offering a new approach to treating HCV.”