Insulin resistance and response to telaprevir plus peginterferon α and ribavirin in treatment-naive patients infected with HCV genotype 1.

Insulin resistance is a predictor of poor response to peginterferon/ribavirin in patients infected with the chronic hepatitis C virus (HCV). There are no data on direct-acting antivirals. This exploratory analysis assessed the effect of metabolic factors and insulin resistance, measured by homoeostatic model assessment (HOMA), on virological response to telaprevir in Study C208. Overall, 161 HCV genotype 1-infected, treatment-naïve patients received 12 weeks of telaprevir plus peginterferon/ribavirin, then 12/36 weeks of peginterferon/ribavirin depending on on-treatment response criteria. The prognostic significance of several factors, including HOMA-insulin resistance (HOMA-IR), on virological response at weeks 4 and 12, end of treatment and 24 weeks after treatment was explored by multiple regression analysis. Baseline HOMA-IR data were available for 147 patients; baseline characteristics were consistent with the overall population. Baseline HOMA-IR <2, 2-4 and >4 was seen in 54%, 30% and 16% of patients, respectively. Neither response rates (any time point) nor week 4 viral load decline were significantly influenced by baseline HOMA-IR. In multivariate analyses, fibrosis stage and low-density lipoprotein cholesterol level were predictive of sustained virological response (OR 0.47 and 1.02, respectively). After the end of treatment, HOMA-IR was significantly lower in patients with sustained virological response than in those without (0.61 vs 1.34 for relapsers and 1.15 for non-responders; p<0.05). In this study, baseline HOMA-IR was not predictive of virological response to telaprevir in HCV genotype 1-infected, treatment-naïve patients, while sustained virological response was associated with improved HOMA-IR. These results suggest that metabolic factors and insulin resistance do not have a significant effect on telaprevir-based treatment efficacy.