Therapeutic drug monitoring of telaprevir in chronic hepatitis C patients receiving telaprevir -based triple therapy is useful for predicting virological response. - Plasma telaprevir concentrations in chronic hepatitis C patients receiving telaprevir -based triple therapy

The rates of undetectable HCV RNA at week 4 (RVR) and at 24 weeks after therapy (sustained virological response: SVR) were 71.4% and 82.9%, respectively. Of patients with RVR, 90% achieved an SVR. The mean TVR C-troughs at days 3 and 7 and weeks 2 and 8 of SVR patients (2748.2, 2733.7, 2999.0, and 2937.8 ng/mL, respectively) was significantly higher than that of non-SVR patients (1616.4, 1788.0, 2314.4, and 2691.1 ng/mL, respectively) (all P<0.05). Multiple logistic regression analysis identified two factors: higher TVR C-trough at day 3 (ng/mL) (odds ratio 1.012, P<0.0001) and prior treatment relapse (odds ratio 6.16 for prior null response, P<0.0001).