A Randomized, Open-Label Study to Evaluate the Safety and Efficacy of Ombitasvir/ABT-450/Ritonavir Co-administered With Ribavirin (RBV) in Adults With Genotype 4 Chronic Hepatitis C Virus (HCV) Infection and Cirrhosis (AGATE-1)

Inclusion Criteria: For Arms A, B and C: \- Participants must meet one of the following: * Treatment-naive: Participant has never received antiviral treatment for hepatitis C infection OR * Treatment Experienced (Prior null responders, Partial responders or Relapsers to IFN/RBV); For Arm D: \- Participant must have prior treatment experience with SOF/pegIFN/RBV or SOF/RBV and meet one of the following categories: * Prior SOF breakthrough/non-responder: HCV RNA detectable at the end of treatment with SOF/pegIFN/RBV or SOF/RBV; * Prior SOF relapser: achieved HCV RNA undetectable at end of a prior treatment course SOF/pegIFN/RBV or SOF/RBV, but HCV RNA was detectable within 52 weeks following completion of therapy. For Arms A, B, C and D: * Chronic HCV genotype 4 infection with cirrhosis. * Participant has plasma HCV RNA level \> 1,000 IU/mL at Screening Exclusion Criteria: * Positive test result at Screening for Hepatitis B surface antigen (HBsAg) or anti-human immunodeficiency virus antibody (HIV Ab). * Current enrollment in another interventional clinical study, previous enrollment in this study, or previous use of any protease inhibitor, non-nucleoside polymerase inhibitor, or Nonstructural viral protein (NS) 5A inhibitor, either investigational or commercially available (including previous exposure to paritaprevir or ombitasvir), or receipt of any investigational product within 6 weeks prior to study drug administration. Prior use of any direct-acting antiviral will not be allowed, except for Arm D where prior experience with the nucleoside polymerase inhibitor, sofosbuvir with pegIFN/RBV or SOF with RBV is required. * Any current or past clinical evidence of Child-Pugh B or C classification or clinical history of liver decompensation including ascites, variceal bleeding, or hepatic encephalopathy. * Confirmed presence of hepatocellular carcinoma. * Any cause of liver disease other than chronic HCV infection. * Abnormal laboratory tests.