Safety, Tolerability, Pharmacokinetics, and Antiviral Activity of GS-5816 in Subjects With Chronic HCV Infection

Administration of GS-5816 will be limited to 3 consecutive days to minimize the potential
development of resistance. All subjects will be monitored for up to 48 weeks post-dose to
determine the persistence of viral mutations. Twelve cohorts are planned for the
examination; within each cohort subjects will receive QD doses of GS-5816 with safety,
antiviral activity and pharmacokinetic assessments evaluated at specified time-points during
the study

Inclusion Criteria:

- HCV treatment-naïve adult subjects (18-65 years of age)with chronic HCV infection and
plasma HCV RNA ≥ 5 log10 IU/mL at screening

- Agree to use protocol defined precautions against pregnancy

Exclusion Criteria:

- Chronic liver disease of a non-HCV etiology (e.g., hemochromatosis, Wilson's disease,
α1 antitrypsin deficiency, cholangitis)

- Evidence of cirrhosis

- Evidence of current drug abuse

- Screening laboratory results outside the protocol specified requirements