subjects chronically infected with hcv genotype 1 or 4

hcv rna viral load of ≥ 100,000 iu/ml

no previous exposure to interferon, pegifnα, or rbv

results of a liver biopsy demonstrating absence of cirrhosis obtained ≤ 24 months prior to randomization. compensated cirrhotics with hcv genotype 1 infection are eligible, but will be capped at 10% of the randomized study population (biopsy can be from any time period prior to randomization)

ultrasound, ct scan, or mri results 12 months prior to randomization that do not demonstrate evidence of hepatocellular carcinoma

body mass index (bmi) of 18 to 35 kg/m²

positive for hepatitis b or hiv-1/hiv-2 antibody at screening

evidence of a medical condition associated with chronic liver disease other than hcv

evidence of decompensated cirrhosis based on radiologic criteria or biopsy