This is a randomized, double-blind (neither physician nor participants know the name of the assigned drug), placebo-controlled study of TMC435 in participants who are infected with genotype 1 hepatitis C virus (HCV), who have never received treatment for HCV infection before. Participants in this study will also receive two other drugs for their HCV infection called peginterferon alpha-2a (PegIFN alpha-2a) and ribavirin (RBV). The purpose of the study is to investigate if TMC435 is superior to placebo in reducing plasma levels of HCV ribonucleic acid (RNA) to an undetectable level 12 weeks after the end of treatment. For the first 12 weeks, participants will take either TMC435 or placebo, plus PegIFNα-2a and RBV. For the next 12 weeks, participants will take PegIFN alpha-2a and RBV only. After that, some participants will continue to take PegIFN alpha-2a and RBV for up to 24 additional weeks and some will stop taking PegIFN alpha-2a and RBV depending on response-guided treatment criteria. The study doctor will inform each participant about how to take their study medication and when they should stop taking it. After a participant stops taking study medication, they will continue to come to the doctor's office for study visits until a total of 72 weeks after they enroll in the study. The total duration of the study is 78 weeks (including screening). Participants will be monitored for safety throughout the study.
