Sofosbuvir/Velpatasvir Fixed-Dose Combination in Adults With Chronic HCV Infection

Key Inclusion Criteria:

- Willing and able to provide written informed consent

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

- Was administered placebo to match SOF/VEL in Gilead study GS-US-342-1138

- HCV RNA ≥ 10^4 IU/mL at screening

- Classification as treatment naive or treatment experienced

- Males and females of childbearing potential who engage in heterosexual intercourse
must agree to use protocol specified method(s) of contraception

Key Exclusion Criteria:

- Current or prior history of clinically-significant illness (other than HCV) or any
other major medical disorder that may interfere with treatment, assessment, or
compliance with the protocol; individuals currently under evaluation for a potentially
clinically-significant illness (other than HCV) are also excluded.

- Screening electrocardiogram (ECG) with clinically significant abnormalities

- Laboratory results outside of acceptable ranges at screening

- Prior exposure to SOF or other nucleotide analogue HCV NS5B inhibitor or any HCV NS5A
inhibitor

- Infection with hepatitis B virus (HBV) or human immunodeficiency virus (HIV)

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