A Randomized, Partially-blind Study to Evaluate the Safety, Tolerability and Effect on Virological Response of Treatment with the HCV Protease Inhibitor RO5190591 in combination with Pegasys and Copegus for 12 weeks, versus treatment with Pegasys and Copegus alone, in Treatment-Naïve Patients with Chronic Hepatitis C Genotype 1 Virus Infection

INTERVENTION: Product Name: HCV Protease Inhibitor Product Code: RO5190591/F02 (ITMN‐191) Pharmaceutical Form: Capsule, soft Current Sponsor code: RO519‐0591/F02 (ITMN‐191) Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 100‐ Pharmaceutical form of the placebo: Capsule, soft Route of administration of the placebo: Oral use Product Name: HCV Protease Inhibitor Product Code: RO5190591/F10(ITMN‐191) Pharmaceutical Form: Capsule, soft Current Sponsor code: RO519‐0591/F10 (ITMN‐191) Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 200‐ Pharmaceutical form of the placebo: Capsule, soft Route of administration of the placebo: Oral use Trade Name: Pegasys Pharmaceutical Form: Solution for injection INN or Proposed INN: pegylated interfron alfa‐2a CAS Number: 198153‐51‐4 Current Sponsor code: Ro 25‐8310 Other descriptive name: pegylated interfron alfa‐2a Concentration unit: µg microgram(s) Concentration type: equal Concentration number: 180‐ Trade Name: Copegus Pharmaceutical Form: Film‐coated tablet INN or Proposed INN: Ribavirin CAS Number: 36791‐04‐5 Current Sponsor code: RO20‐9963 Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 200‐ CONDITION: Chronic Hepatitis C Genotype 1 Virus Infection (Treatment‐Naive Patients) ; MedDRA version: 9.1 Level: LLT Classification code 10008912 Term: Chronic hepatitis C PRIMARY OUTCOME: Main Objective: To evaluate the safety, tolerability, and effect on virological response of a 12 weeks duration of RO5190591 incombination with Pegasys and Copegus compared to thecombination of Pegasys and Copegus alone in treatment‐naïvepatients with chronic hepatitis C genotype 1 virus infection Primary end point(s): The primary measure of efficacy is SVR defined as the percentage of patients with; undetectable HCV RNA as measured by the Roche COBAS TaqMan HCV Test; (detection limit = 15 IU/mL) 24 weeks after end of treatment (SVR‐24; a single last HCV RNA undetectable = 20 weeks after last dose). Patients without HCV RNA; measurements at the end of the 24‐week treatment‐free follow‐up period will be; considered non‐responders. This definition of SVR will be “SVR according to actual; treatment period”. Secondary Objective: To evaluate the pharmacokinetics of RO5190591 in combination with Pegasys and Copegus; To evaluate the viral resistance profile of RO5190591 in combination with Pegasys and Copegus INCLUSION CRITERIA: 1. Age 18 years and older 2. Serologic evidence of CHC infection by an anti‐HCV antibody test (current or historical) 3. Evidence of chronic hepatitis C infection > 6 months duration 4. Evidence of hepatitis C genotype 1 infection by molecular assay 5. Serum HCV RNA quantifiable at = 50,000 IU/mL as demonstrated by the Roche COBAS TaqMan HCV Test 6. HCV treatment‐naïve (i.e. have never received treatment for CHC, including but not limited to IFN‐based therapy, ribavirin, or other anti‐viral agents with established or perceived activity against the HCV virus) 7. Liver biopsy within the past 24 months showing clear absence of advanced fibrosis or cirrhosis (as indicated in Appendix 1). Liver biopsy should be scored using one of the scoring methods in Appendix 1. 8. Normal cardiac troponin I (cTnI) value at the screening visit (< 0.100 ng/mL) 9. Serum total bilirubin value at the screening visit within the reference range 10.