The US Food and Drug Administration has approved a new hepatitis C drug telaprevir (Incivek), the agency announced today.
Telaprevir is a direct-acting antiviral drug (an HCV protease inhibitor), licensed for use in combination with the current standard treatment, pegylated interferon and ribavirin.
The drug has been developed by Vertex, which will market the drug in the United States.
Telaprevir is the second HCV protease inhibitor to be approved this month. The US Food and Drug Administration approved boceprevir (Victrelis) on 13 May.
The safety and effectiveness of telaprevir was evaluated in three phase 3 clinical trials with about 2250 adult patients who were previously untreated, or who had received prior therapy. In all studies, patients also received the drug with standard of care. In previously untreated patients, 79% of those receiving telaprevir experienced a sustained virologic response (i.e. the infection was no longer detected in the blood 24 weeks after stopping treatment), compared to standard treatment alone.
The sustained virologic response for patients treated with telaprevir across all studies, and across all patient groups, was between 20 and 45% higher than current standard of care.
The studies indicate that hepatitis C treatment can be shortened from 48 weeks to 24 weeks in most patients when telaprevir is used in the first 12 weeks. Sixty per cent of previously untreated patients achieved an early response and received only 24 weeks of treatment (compared to the standard of care of 48 weeks). The sustained virologic response for these patients was 90%.
Telaprevir is dosed as two pills taken three times a day with food. It should be taken in combination with pegylated interferon and ribavirin for the first 12 weeks. Most people with a good early response to the combination regimen at 12 weeks can be treated for 24 weeks rather than the recommended 48 weeks of treatment with the standard care.
The most commonly reported side-effects in patients receiving telaprevir in combination with pegylated interferon and ribavirin include rash, low red blood cell count (anaemia), nausea, fatigue, headache, diarrhea, itching (pruritus), and anal or rectal irritation and pain.
Rash can be serious and can require stopping Incivek or all three drugs in the treatment regimen.
Telaprevir is expected to receive European Union marketing approval in the second half of 2011.