Once-daily simeprevir with peginterferon and ribavirin for treatment-experienced HCV genotype 1-infected patients in Japan: the CONCERTO-2 and CONCERTO-3 studies.

BACKGROUND: Efficacy of available therapies for patients with HCV who have previously failed treatment is limited. Two Phase III, open-label trials in Japan investigated efficacy and safety of simeprevir and peginterferon-α-2a/ribavirin (PR) combination therapy in treatment-experienced patients with genotype 1 HCV infection.

METHODS: In CONCERTO-2, prior non-responders to IFN-based therapy (N = 106) received simeprevir (TMC435) 100 mg QD with PR for 12 (SMV12, n = 53) or 24 weeks (SMV24, n = 53) followed by response-guided therapy (RGT) with PR for 12/36 (SMV12) or 0/24 (SMV24) weeks. In CONCERTO-3, relapsers after IFN-based therapy (N = 49) received simeprevir 100 mg QD with PR for 12 weeks followed by RGT with PR for 12/36 weeks. Primary endpoints were the rates of sustained virologic response 12 weeks after treatment end (SVR12).

RESULTS: SVR12 rates were 52.8% (SMV12) and 35.8% (SMV24) for prior non-responders, and 95.9% for prior relapsers (SMV12; p ≤ 0.0001 vs null hypothesis, respectively). Most prior non-responders (SMV12: 81.1%; SMV24: 73.6%) and prior relapsers (95.9%) met RGT criteria and completed PR to Week 24. Of these, 60.5%, 48.7%, and 95.7%, respectively, achieved SVR12. Viral breakthrough occurred in 13.2 % (SMV12) and 11.3% (SMV24) of prior non-responders; no viral breakthrough occurred in prior relapsers. Viral relapse occurred in 38.6% (SMV12) and 51.1% (SMV24) of prior non-responders and 8.2% of prior relapsers. Simeprevir with PR was generally well tolerated in both studies.

CONCLUSION: Re-treatment with 12 weeks of simeprevir QD with PR provided high SVR in treatment-experienced patients with chronic HCV genotype 1 infection, and allowed most patients to complete treatment in 24 weeks.