To assess efficacy (SVR rate) of MK5172 / MK8742 for 12 weeks without RBV in G1b patients with compensated cirrhosis (Child-Pugh A5 to A6) previously failing first gen. PI or non responders to PR.

Inclusion Criteria:

1. Informed consent form signed,
2. Age > 18 years,
3. Chronic infection with Hepatitis C virus genotype 1b,
4. HCV RNA > 100 IU/mL,
5. HCV patients previously treated by PR with no response or previously treated with first generation PIs (boceprevir, telaprevir, simeprevir) and failing therapy,
6. Subjects with compensated cirrhosis with Child-Pugh score ranging between A5 to A6. Cirrhosis defined by liver biopsy (METAVIR F4) or non-invasive methods (transient elastography (FibroScan) > 12.5 KPa; or FibroTest or FibroSure > 0.75 with APRI >2),
7. Hepatic Venous Pressure Gradient (HVPG) > 6 mmHg (only in selected sites),
8. Albumin level ≥ 3.0 g/dl,
9. Platelet count ≥ 75 x 103/μL.

Exclusion Criteria:

1. Child-Pugh score greater than CP-A6,
2. Patients with HCV genotype 1a, 2, 3, 4, 5, 6,
3. Have any serious or active medical illness which, in the opinion of the investigator, would interfere with subject treatment, assessment, or compliance,
4. HIV or chronic hepatitis B virus (HBV) infection (HBsAg positive),
5. Decompensated cirrhosis/previous decompensation,
6. Pregnancy,
7. Breast-feeding,
8. Known hypersensitivity to Grazoprevir, Elbasvir or any of its components,
9. Albumin level < 3.0 g/dl,
10. Platelet count < 75 x 103/μl,
11. Concomitant participation in any clinical trial.