A Study to Assess the Effectiveness, Safety, and Pharmacokinetics of TMC435 in Combination With Peginterferon Alfa-2a and Ribavirin in Hepatitis-C Infected Patients

A Phase II, Randomized, Open-label Study in Japan to Investigate the Efficacy, Safety and Pharmacokinetics of TMC435 as Part of a Treatment Regimen Including Peginterferon Alfa-2a and Ribavirin in Treatment naïve, Genotype 1, Chronic Hepatitis C Subjects

The purpose of this study is to evaluate effectiveness, safety and pharmacokinetics (Explores what the body does to the medication) of TMC435350 in combination with Peginterferon Alfa-2a and Ribavirin in genotype 1 hepatitis C virus infected Japanese participants who have never received treatment for their hepatitis C infection.

This is a Phase 2, randomized (The study medication is assigned by chance.), 5-arm, open label (All people know the identity of the intervention.), multicentre (study conducted at multiple sites) study. Approximately, 84 participants will be randomized to 5 different arms in a 2:2:1:1:1 ratio. In treatment arms 1 and 2, participants will receive 12 weeks of triple therapy (use of 3 medications) with TMC435 50 or 100 mg once daily plus Peginterferon Alfa-2a and Ribavirin followed by 12 weeks of treatment with Peginterferon Alfa-2a and Ribavirin. In treatment arms 3 and 4, participants will receive 24 weeks of triple therapy with TMC435 50 or 100 mg once daily plus Peginterferon Alfa-2a and Ribavirin. In treatment arm 5 (control group), participants will receive Peginterferon Alfa-2a and Ribavirin for 48 weeks. This study will consist a screening phase of upto 6 weeks, treatment phase of upto 48 weeks and a post treatment follow-up period of 24 weeks. Safety evaluations will include assessment of adverse events, clinical laboratory tests, vital signs, and cardiovascular safety.

Inclusion Criteria:

• Participants with documented chronic hepatitis C infection as evidenced by presence of HCV antibody at least 6 months (180 days) prior to the informed consent. - Participants with genotype 1 HCV infection. - Participants with plasma HCV RNA level of ≥ 5.0 log10 IU/mL at screening.

Exclusion Criteria:

• Participants diagnosed with hepatic cirrhosis or hepatic failure. - Participants with any other liver disease than hepatitis C. - Participants with infection/co-infection with non-genotype 1 HCV.