Reduction of HCV RNA from baseline to an early time point during SMV/PR therapy was determined for Y93H RAV and the Y93 wild type. Within 7 days of the initiation of therapy, HCV RNA reduction was significantly greater for Y93H RAV (-3.7 ± 1.3 logIU/mL/day) than the Y93 wild type (-3.4 ± 1.0 logIU/mL/day) (p<0.001).