What's new in HCV genotype 2 treatment

Genotype 2 (HCV-2) accounts for 8% of the patients with chronic hepatitis C virus in Europe. Because of the favourable response to interferon (IFN)-based treatment, this group is considered an 'easy-to-treat' genotype along with HCV-3. However, experimental and clinical data suggest possible differences between HCV-2 and -3. Recently, subtle differences in treatment efficacy have also been shown in response-guided treatment studies. In these studies, the duration of pegylated interferon (PEG-IFN) and ribavirin (RBV) treatment was tailored according to treatment response. Although SVR rates were similar between HCV-2 and HCV-3 patients after a rapid virological response (RVR), in the absence of RVR, the rates were lower in HCV-3 than in HCV-2. The triple combination treatment, including direct-acting antivirals (DAA) that will be commercialized in the coming months might increase SVR rates in this particular subgroup of patients. According to existing results, telaprevir might be beneficial in HCV-2 but not in HCV-3 patients. A nucleotide analogue polymerase inhibitor, PSI-7977 by Pharmasett has been shown to be active against both. The role of the IL28B polymorphism as a predictor of response to the current standard of care (SoC), PEG-IFN and RBV treatment is the subject of debate, but this mainly seems to be because of the small size of the samples in the studies performed so far. Existing results suggest that the genetic evaluation of IL28B may be useful in patients with HCV-2 for predicting response in patients without RVR.