This 4-arm study will compare the efficacy and safety of PEGASYS induction and maintenance dosing, versus standard fixed dosing in combination with Copegus, and the efficacy and safety of higher dose versus standard dose Copegus in combination with PEGASYS. Patients with chronic hepatitis C (CHC) genotype 1 infection of high viral titer, and baseline body weight ≥85 kg, will be randomized to one of 4 groups, to receive one of the following: a) PEGASYS 180 µg subcutaneously (sc) weekly plus Copegus 1200 mg orally (po) daily; b) PEGASYS 180 µg sc weekly plus Copegus 1400-1600 mg po daily; c)PEGASYS 360 µg sc weekly (induction) followed by 180 µg sc weekly (maintenance) plus Copegus 1200 mg po daily; or d) PEGASYS 360 µg sc weekly (induction) followed by 180 µg sc weekly (maintenance) plus Copegus 1400-1600 mg po daily. Following 48 weeks treatment, there will be a 24-week period of treatment-free follow-up. The anticipated time on study treatment is 3-12 months, and the target sample size is 500+ individuals.