Results from an ongoing Phase IIa study showed that MK-7009, Merck Sharp and Dohme's (MSD) investigational oral hepatitis C virus (HCV) protease inhibitor, in combination therapy significantly improved rapid viral response, defined as viral suppression to undetectable levels within 28 days, compared to placebo in combination therapy in previously untreated (treatment-na??ve) patients infected with chronic HCV genotype 1, one of the most difficult to treat genotypes of HCV (p Viral suppression continued in the majority of patients following termination of MK-7009 treatment at day 28. At day 42, HCV RNA was undetectable in 77 to 94 percent of the patients in the regimens that had contained MK-7009 versus 12 percent of patients in the regimen that had contained placebo (p