Inclusion Criteria Part 3:

• Males or females of non-childbearing potential aged 18 to 65 years. Females must be surgically sterile, or post-menopausal for at least 12 months. Females of child-bearing potential may be enrolled provided they use two methods of acceptable contraception.
• Diagnosed with chronic liver disease consistent with chronic hepatitis C infection, genotype-1, for at least 6 months.
• Genotype 1 Patients who are HCV treatment-naive, with no history of exposure to interferon, ribavirin, or direct antivirals; OR Genoytpe 2 or 3 patients who have previously been treated with interferon.
• Otherwise healthy as determined at screening.
• At least one measurement of serum HCV RNA of ≥ 100,000 IU/mL measured during Screening by the COBAS AmpliPrep/COBAS TaqMan HCV.
• ALT and AST measurement at Screening < 5 times of ULN.
• Liver biopsy obtained within 2 years (24 calendar months) prior to Screening with a fibrosis classification of non-cirrhotic as judged by a local pathologist. Incomplete cirrhosis (Ishak 5) is also considered as cirrhosis. If no history of liver biopsy, a study qualifying biopsy must be performed during the screening period, prior to randomization.
• Negative pregnancy test (for all females) at Screening and Day -1.
• All male patients with female partners of child-bearing potential must use two acceptable methods of contraception (one of which must be a barrier method), during and for 3 months after participation in the study.
• A body mass index (BMI) of ≥ 18 kg/m2, but not exceeding 36.
• Able to abstain from any alcohol (including alcohol-containing products) and able to limit caffeine consumption to two 8-ounce cups of coffee or the equivalent per day, from 72 hours before receiving study drug through the end of the study (Day 56 or early termination).
• Able to effectively communicate with the Investigator and other testing center personnel.
• Able to participate and willing to give written informed consent and comply with the study restrictions.

Exclusion Criteria

• Positive test at Screening for HAV, HBV, or HIV.
• History or other evidence of a medical condition associated with chronic liver disease, decompensated liver disease, renal disease, immunologically mediated disease, chronic pulmonary disease, cardiac disease, thyroid disease, severe retinopathy, severe psychiatric disease, organ transplantation, cancer, seizure disorder, or pancreatitis.
• Abnormal hematological, biochemical, or coagulation parameters at Screening; or positive fecal occult blood test.
• Estimated creatinine clearance of 90 mL/minute or less at Screening.
• Poorly controlled hypertension, or anyone who at screening or baseline has a BP of 140/90 or greater.
• Type 1 or 2 diabetics with hemoglobin A1C > 7.
• A baseline increased risk for anemia.
• Screening ECG QTc value ≥ 450 ms and/or clinically significant ECG findings.
• Positive results for drugs of abuse at Screening.
• History of clinically significant drug allergy to nucleoside/nucleotide analogues.
• Donation or loss of more than 400 mL blood within 2 months prior to anticipated dose administration.
• Participation in a clinical study with an investigational drug, biologic, or device within 3 months prior to anticipated dose administration.
• Males whose female partner is pregnant.
• Any chronic viral (including HSV), bacterial, mycobacterial, fungal, parasitic, or protozoal infection.
• Serum alpha-feto-protein > 50 ng/mL at screening.
• Receipt of any vaccination within 30 days prior to anticipated dose administration.