Conditions: Chronic Hepatitis C
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 301
Healthy volunteers: no

Brief summary:
This is a 2-part study. The purpose of Part A is to assess the efficacy and safety of grazoprevir (MK-5172) 100 mg in combination with elbasvir (MK-8742) 50 mg for 12 weeks in the treatment of chronic HCV GT1, GT4, or GT6 infection in treatment-naïve participants who are on opiate substitution therapy (OST). The primary hypothesis is that the percentage of participants who receive grazoprevir/elbasvir fixed-dose combination (FDC) in the Immediate Treatment Arm and achieve a Sustained Virologic Response 12 weeks after the end of all study therapy (SVR12) will be superior to 67%. In addition, participants who received at least 1 dose of grazoprevir/elbasvir in Part A will be eligible to participate in Part B, which is a 3-year observational follow-up.

Detailed description:

Arms:
arm 1: In Part A, participants receive grazoprevir 100 mg plus elbasvir 50 mg FDC (MK-5172A) once daily for 12 weeks (blinded) and were followed-up for 24 weeks. In Part B, participants could enroll in a 3-year follow-up period where they were followed every 6 months for 3 years in an observational cohort (no treatment was administered during Part B). arm 2: In Part A, participants receive placebo to MK-5172A once daily for 12 weeks (blinded), followed by 4 weeks of follow-up. Afterwards, participants received 12 weeks of open-label treatment with the MK-5172A FDC and were followed-up for 24 weeks. In Part B, participants could enroll in a 3-year follow-up period where they were followed every 6 months for 3 years in an observational cohort (no treatment was administered during Part B).

Interventions: intervention 1: Grazoprevir 100 mg/Elbasvir 50 mg FDC tablet (MK-5172A) intervention 2: Placebo to Grazoprevir 100 mg/Elbasvir 50 mg FDC tablet
Intervention descriptions: intervention 1: Grazoprevir 100 mg/Elbasvir 50 mg FDC tablet, taken once daily by mouth for 12 weeks. intervention 2: Placebo Grazoprevir 100 mg/Elbasvir 50 mg FDC tablet, taken once daily by mouth for 12 weeks.

Protocol document: