Participants in the 3 treatment groups were similar with respect to baseline characteristics, with the exception that the placebo group included a higher percentage of white participants (Table 1). Most participants were men (71%); the median age was 54 years, and the median body mass index was 29.2 (calculated as weight in kilograms divided by height in meters squared). The majority of patients had HCV genotype 1 infection (91%). The median HCV RNA level was 6.2 log10 IU/L and was similar in the 3 treatment groups. Serum ALT levels did not differ significantly (median, 106 U/L for placebo; 110 U/L for 420-mg silymarin; and 105 U/L for 700-mg silymarin; P=.90) across treatment groups. Markers suggestive of advanced liver disease (serum bilirubin levels, albumin levels, platelet counts) did not differ significantly across treatment groups.