Participants with genotype 1 HCV infection were randomized to 1 of 3 sofosbuvir doses (100
mg, 200 mg, or 400 mg) or matching placebo once daily based upon stratification for IL28B
status (CC or CT/TT). Placebo tablets were administered to participants receiving 100 mg
active sofosbuvir (3 placebo tablets) and 200 mg active sofosbuvir (2 placebo tablets) in
order to maintain the study blind. Participants received sofosbuvir/matching placebo from Day
0 to 27. Participants also received treatment with PEG+RBV starting on Day 0 of the study
which continued for 48 weeks. Participants were evaluated for sustained virologic response
(SVR) for an additional 24 weeks following completion of study treatment.