This Registry is designed to obtain long term data on participants who have failed to achieve sustained virologic response (SVR) while receiving at least one Gilead oral antiviral agent (OAV) in a previous Gilead-sponsored hepatitis C virus (HCV) study.

Key Inclusion Criteria:

• Have previously participated in a Gilead-sponsored hepatitis C study and received at least one Gilead OAV
• Have failed to achieve an SVR in a previous Gilead-sponsored study, as defined in the original treatment protocol
• Provide written, informed consent
• Be willing and able to comply with the visit schedule

Key Exclusion Criteria:

• Individuals planning to start a new course of hepatitis C therapy including any investigational drug or device during the course of the follow-up Registry
• History of clinically significant illness or any other major medical disorder that may interfere with follow-up, assessments or compliance with the protocol

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

Participants who have failed to achieve sustained virologic response (SVR) while receiving at least one Gilead OAV in a previous Gilead-sponsored HCV study.