Durability of Virologic Response and/or Viral Resistance Patterns in Participants With Chronic Hepatitis C Who Have Been Previously Treated With Grazoprevir (MK-5172) (MK-5172-017)

This is a three-year (except for participants with chronic kidney disease \[CKD\] or cirrhosis) multicenter study to follow participants who received at least one dose of grazoprevir (MK-5172) in a previous study to determine whether they remain hepatitis C virus (HCV)-Ribonucleic acid (RNA) negative over time, and to determine if they have developed antiviral resistance. The study will also evaluate long-term adverse events in this population. Participants from MK-5172-052 (NCT02092350) with CKD or cirrhosis will be followed for five years.

As of Amendment 03, the study design is revised such that continued enrollment will only be for participants who failed prior therapy with a grazoprevir regimen. Participants with CKD enrolled from MK-5172-052 (NCT02092350) will continue enrollment regardless of prior treatment-response and remain in this study for five years, while participants enrolled from all other studies with HCV RNA less than the lower limit of quantitation (LLOQ) will be discontinued and end their participation after the next scheduled visit. In addition, participants who receive other HCV treatments concurrent with this follow-up study or received other HCV treatments prior to this study will be discontinued and their data excluded from analysis. As of Amendment 04, the protocol has been updated to include enrollment of pediatric participants from protocol MK-5172-079 (NCT03379506). Enrollment is limited to participants who experienced virologic failure associated with 1 or more treatment-emergent resistant associated substitutions (RASs) present at 12 weeks after receiving grazoprevir treatment in prior treatment study MK-5172-079 (NCT03379506).