[METHODS] In the QUEST-2 , phase 3 study , done at 76 sites in 14 countries ( Europe , and North and South Americas ) , patients with confirmed chronic HCV genotype 1 infection and no history of HCV treatment were randomly assigned with a computer-generated allocation sequence in a ratio of 2:1 and stratified by HCV genotype 1 subtype and host IL28B genotype to receive simeprevir ( 150 mg once daily , orally ) , peginterferon alfa 2a ( 180 g once weekly , subcutaneous injection ) or 2b ( according to bodyweight ; 50 g , 80 g , 100 g , 120 g , or 150 g once weekly , subcutaneous injection ) , plus ribavirin ( 1000-1200 mg/day or 800-1400 mg/day , orally ; simeprevir group ) or placebo ( once daily , orally ) , peginterferon alfa 2a or 2b , plus ribavirin ( placebo group ) for 12 weeks , followed by just peginterferon alfa 2a or 2b plus ribavirin .