 This is a multicenter, randomized study drug is assigned by chance, double-blind neither sponsor, physician nor patient knows the name of the assigned study drug, Phase III study to compare the efficacy, tolerability and safety of TMC435 in development for treatment of chronic hepatitis C virus HCV infection versus placebo a preparation containing no drug used as control as part of a treatment regimen including peginterferon-alpha PegIFNα-2a and ribavirin RBV both current therapies for HCV in adult treatment-naïve patients patients who have never taken HCV medications with genotype 1 Hepatitis C virus HCV infection. The study will consist of a screening period with a maximum duration of 6 weeks, a response guided 24- or 48-week TMC435 treatment groups or 48-week control group treatment period, and a post-therapy follow-up period up to 72 weeks after the start of treatment. Patients will be randomly assigned in a 1:1:1 fashion to receive TMC435 or placebo, stratified by HCV genotype 1 subtype and IL28B genotype within each country. In the first 24 weeks, patients will receive 12 weeks TMC435 100 or 150 mg or placebo once-daily q.d. plus PegIFNα-2a plus RBV, after which they will continue with PegIFNα-2a and RBV. Response-guided treatment criteria will be used to determine PegIFNα-2a and RBV total treatment duration of 24 or 48 weeks for patients in the TMC435 treatment groups. In the control group, all patients will be required to complete 48 weeks of treatment with PegIFNα-2a and RBV. In all 3 treatment groups, there will be a post-therapy follow-up period up to 72 weeks after the start of treatment. The total study duration for each patient will be a maximum of 78 weeks including the 6-week screening period. 