To evaluate the effect of ribavirin on second phase plasma hepatitis C virus (HCV) ribonucleic acid (RNA) decline in participants who receive ombitasvir/ABT-450/ritonavir and dasabuvir with full dose ribavirin, low dose ribavirin or without ribavirin for 2 weeks in treatment-naive HCV genotype (GT) 1a-infected adults.

Inclusion Criteria:

1. Screening laboratory result indicating HCV genotype 1 (GT1) a infection.
2. Chronic HCV infection.
3. Subjects must be non-cirrhotic.
4. Subjects must be able to understand and adhere to the study visit schedule and all protocol requirements as well as voluntarily sign and date an institutional review board (IRB) approved informed consent.

Exclusion Criteria:

1. Women who are pregnant or breastfeeding.
2. Positive test result for hepatitis B surface antigen (HBsAg) or anti-human immunodeficiency virus antibody (HIV Ab) positive immunoassay.
3. Clinically significant abnormalities or co-morbidities, other than HCV infection, that make the subject unsuitable for this study or treatment.
4. Current enrollment in another interventional clinical study. Previous use of any HCV treatments including pegylated interferon (pegIFN), ribavirin, or any direct acting antiviral agent, either investigational or approved, for HCV including protease inhibitors, nucleoside or non-nucleoside polymerase inhibitors, or nonstructural viral protein 5A (NS5A) inhibitors.
5. History or solid organ transplant.
6. Screening laboratory analysis that shows abnormal results.