The primary objective for Part 3 is to assess the safety, tolerability and pharmacokinetics of RO5024048 in treatment-naive HCV Genotype 1-infected patients, and in non-responder HCV Genotype 2/3-infected patients, after once or twice daily dosing in combination wtih PEG-IFN and RBV for 28 days on an outpatient basis. The secondary objective of Part 3 (COMBO) is to evaluate the short-term decrease in viral load in treatment-naive HCV Genotype 1-infected patients, and in non-responder HCV Genotype 2/3-infected patients, after once or twice daily dosing of RO5024048 in combination with PEG-IFN and RBV for 28 days.