CP-065 Effectiveness in genotypes 1B, 1A in patients with hepatitis C virus infection treated with telaprevir-based treatment

Background Hepatitis C virus genotype 1a (HCV-1a) is a predictor of poor response to peginterferon-ribavirin treatment, which has been associated with a lower resistance barrier, compared to HCV genotype 1b (HCV-1b). Variations in the human IL28B genotypes CC, CT or TT have also been associated with a person’s response to treatment for hepatitis C. Studies have shown that people with the CC variation respond better to treatment with pegylated-interferon and ribavirin than those with the CT or TT variations.; Purpose To assess the differences in effectiveness between HCV-1a and HCV-1b in patients with HCV treated with telaprevir-based treatment. Materials and methods Retrospective study of patients treated with peginterferon-ribavirin-telaprevir. Demographic and pathological data, response at 4 and 12 weeks (HCV-RNA <1000) and at 24, 36, 48 weeks of treatment (HCV-RNA undetectable), sustained virological response after 12 weeks of treatment (SVS12), adverse effects and discontinuation were collected in an Access database and analysed with SPSS vs12. Results Of 79 patients (57 male), 59.5% were infected with HCV-1b, 59.5% presented fibrosis F3-F4 and 70.9% were pretreated (mainly relapsers 58.9%). Of those with HCV-1a 57.7% had the CT variant of the IL28 genotype, 26.9% CC and 15.4% TT and in those with HCV-1b 71.1% had the CT variant, 15.6% CC and 13.3% TT. There were significant differences in age: a median age of 50 (34–66) in HCV-1a-infected patients and 57 (42–76) in HCV-1b (p = 0.002). Of patients with HCV-1a 68% were monoinfected and 32% had both variants. Of patients with HCV-1b 96.3% were HCV monoinfected and 3.7% were coinfected. 34.2% discontinued treatment. No statistical difference was found in response at 4, 12, 24, 36 and 48 weeks of treatment and SVR12, but there was a trend towards a lower SVR12 in HCV-1b (75% vs. 100% in HCV-1a). No significant differences were found in cutaneous rash or anaemia (haemoglobin level <10 g/dL). Within each group discontinuation was higher in HCV-1a (43.8%) than in HCV-1b (27.7%) although it was not statistically significant, mainly due to virological failure (64.3%) and adverse effects (46.2%). Conclusions The sustained virological response (SVR12) rates in HCV-1a group are better than in HCV-1b, not worse, which might be attributed to a higher frequency of genotype CC and a lower frequency of CT in people infected with it than in those infected with HCV-1b. Further studies are required because of the small sample size and more data of sustained virological response are needed. No conflict of interest.