['hepatitis c virus infection']
['ldv/sof', 'placebo']

        Inclusion Criteria:

          -  Chronic HCV infection (≥ 6 months) documented by prior medical history or liver biopsy

          -  Chronic genotype 1 HCV infection

          -  Screening laboratory values within defined thresholds

          -  Use of protocol-specified method(s) of contraception if female of childbearing
             potential or sexually active male

        Exclusion Criteria:

          -  Clinically-significant illness (other than HCV) or any other major medical disorder
             that may interfere with treatment, assessment, or compliance with the protocol.
             Current or prior history of any of the following:

               -  Hepatic decompensation

               -  Solid organ transplantation

               -  Significant pulmonary or cardiac disease

               -  Chronic liver disease of a non-HCV etiology

               -  Hepatocellular carcinoma (HCC)

               -  Infection with hepatitis B virus (HBV)

               -  Infection with human immunodeficiency virus (HIV)

               -  History of recent epilepsy (within 2 years of screening) or cerebral vascular
                  accident (CVA)

               -  Structural brain damage

          -  Presence of cirrhosis

          -  Contraindication to MRI

          -  Pregnant or nursing female

          -  Prior treatment NS5A directly-acting antiviral agent. Any interferon (IFN)-containing
             regimen within 8 weeks of Screening
      