Efficacy and Safety of Grazoprevir (MK-5172) and Uprifosbuvir (MK-3682) With Elbasvir (MK-8742) or Ruzasvir (MK-8408) for Chronic Hepatitis C Genotype (GT)1 and GT2 Infection (MK-3682-011)

This is a randomized, three-part, open-label trial of grazoprevir (GZR; MK-5172) (100 mg) and uprifosbuvir (UPR; MK-3682) (300 mg or 450 mg), with either elbasvir (EBR; MK-8742) (50 mg) or ruzasvir (RZR; MK-8408) (60 mg), and with or without ribavirin (RBV), in treatment-naïve (TN) cirrhotic (C) or non-cirrhotic (NC) hepatitis C virus (HCV) participants with chronic HCV genotype (GT) 1 or GT2 infection. Part A will consist of 8 arms to evaluate the safety of dose combinations. In Part B, participants will take 2 UPR+GZR+RZR fixed dose combination (FDC) tablets once daily (q.d.) by mouth, with or without twice-daily (b.i.d.) RBV (200 mg capsules; weight-based dosing). Participants who relapse following completion of therapy in Part A will be offered the option of retreatment with 16 weeks of UPR+GZR+RZR with RBV in Part C (data obtained from Part C will not be used in the analysis of outcome measures).