Efficacy and Safety of Ledipasvir/Sofosbuvir, With or Without Ribavirin, in HCV Infected Participants Who Have Failed Prior Treatment With Sofosbuvir-based Therapies

A Phase 3b, Multicenter, Open-Label Study to Investigate the Efficacy and Safety of Ledipasvir/Sofosbuvir, With or Without Ribavirin, in HCV Infected Subjects Who Have Failed Prior Treatment With Sofosbuvir-based Therapies

The primary objective of this study is to evaluate the efficacy, safety, and tolerability of ledipasvir/sofosbuvir (LDV/SOF) fixed dose combination (FDC) for 12 weeks with or without ribavirin (RBV) in participants without cirrhosis, and LDV/SOF FDC for 12 weeks with RBV or LDV/SOF FDC for 24 weeks without RBV in participants with cirrhosis.

Key Inclusion Criteria:

• HCV RNA > 15 IU/mL at screening
• HCV genotype 1 or 4
• Chronic HCV infection (≥ 6 months)
• Prior virologic failure after treatment with SOF in combination with simeprevir (SMV) ± RBV or with RBV ± pegylated interferon (PEG)
• Cirrhotic and non-cirrhotic as determined by standard methods
• Male and female individuals of childbearing potential who engage in heterosexual intercourse must agree to use protocol specified method(s) of contraception

Key Exclusion Criteria:

• Prior exposure to approved or experimental non-structural protein (NS5A) inhibitors
• Prior exposure to nucleos(t)ide polymerase inhibitors, other than SOF
• Pregnant or nursing female or male with pregnant female partner
• Coinfection with HIV or hepatitis B virus
• Current or prior history of clinical hepatic decompensation
• Hepatocellular carcinoma or other malignancy (with exception of certain resolved skin cancers)
• Chronic use of systemic immunosuppressive agents
• History of clinically significant illness or any other medical disorder that may interfere with individual's treatment, assessment or compliance with the protocol

Note: Other protocol defined Inclusion/Exclusion criteria may apply.