Patient description: A 53-year-old man presents with chronic HCV infection for the past 2 years. His past medical history is only significant for inguinal hernia surgery when he was 20 years old. He is on IFN (100 mg/week) plus RBV (400 mg/day) combination therapy for the past 9 months. Direct antiviral drugs were added to his treatment 6 months ago. His medical record shows previous positive HCV RNA tests as well as positive enzyme immunoassay for anti-HCV-antibodies. The recent biopsy was negative for hepatocellular carcinoma and was only remarkable for chronic inflammation compatible with a chronic viral hepatitis. There is no evidence of alcoholic liver disease, bleeding from esophageal varices, hemochromatosis, autoimmune hepatitis or metabolic liver disease. He is an alert male with no acute distress. His BP: 130/75, HR: 90/min and BMI: 27. His abdomen is soft with no ascites or tenderness. The lower extremities are normal with no edema.

Clinical trial eligibility criteria: eligible ages (years): 18.0-65.0,  Hepatitis C A subject will be eligible for in this study only if all of the following apply: Healthy as determined by a responsible and experienced physician, based on a medical evaluation including medical history, physical examination, laboratory tests and cardiac monitoring (i.e., ECG), including no cardiac, pulmonary, hepatic, biliary, gastrointestinal, or renal disorders, or cancer within the past 5 years Males or females between 18 and 65 years of age inclusive, at the time of signing the informed consent A female subject is eligible to participate if she is of non-childbearing potential Body weight > or = 50 kg (110 lbs.) for men and > or = 45 kg (99 lbs.) for women and BMI between 18.5-35.0 kg/m2 inclusive will be allowed Capable of giving written informed consent, which includes compliance with the requirements and restrictions listed in the consent form AST, ALT, and alkaline phosphatase <3.0xULN and bilirubin <1.5xULN (isolated bilirubin >1.5xULN is acceptable if bilirubin is fractionated and direct bilirubin <35%) Average QTcB or QTcF < 450 msec; or QTcB or QTcF < 480 msec in subjects with Bundle Branch Block Treatment naive chronically infected HCV subjects, defined as infection for >6 months and no prior HCV therapy, with an HCV RNA viral load of greater than 100,000 IU/mL and HCV genotype 1a or 1b. HCV subjects with mixed genotypes are not eligible for the study Positive for HCV RNA and anti-HCV antibody at the time of screening AND positive for anti-HCV antibody, HCV RNA, or an HCV genotype at least 6 months before screening; OR Positive for HCV RNA and anti-HCV antibody at the time of screening AND liver biopsy within three years prior to screening indicating the absence of cirrhosis  Unwillingness or inability to follow the procedures outlined in the protocol Subject is mentally or legally incapacitated A positive pre-study Hepatitis B surface antigen or HIV antibody within 3 months of screening A positive pre-study drug/alcohol screen History of regular alcohol consumption within 6 months of the study Consumption of red wine, seville oranges, grapefruit or grapefruit juice and/or pummelos, exotic citrus fruits, grapefruit hybrids or fruit juices from 7 days prior to the first dose of study medication The subject has participated in a clinical trial and has received an investigational product within the following time period prior to the first dosing day in the current study: 30 days, 5 half-lives or twice the duration of the biological effect of the investigational product (whichever is longer). Exposure to more than four new investigational products within 12 months prior to the first dosing day Use of prescription or non-prescription drugs, including vitamins, herbal and dietary supplements (including St John's Wort) within 7 days (or 14 days if the drug is a potential enzyme inducer) or 5 half-lives (whichever is longer) prior to the first dose of study medication History of sensitivity to any of the study medications, or components thereof or a history of drug or other allergy that, in the opinion of the investigator or GSK Medical Monitor, contraindicates their participation Where participation in the study would result in donation of blood or blood products in excess of 500 mL within a 56 day period