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): 18.0-999.0,  Chronic Hepatitis C Age above 18 years, male or female. Elevated alanine (ALT) or asparate (AST) aminotransferase activities averaging at least twice the upper limit of normal on three determinations taken at least one month apart during the previous 6 months. The mean of these three determinations will be defined as "baseline" ALT and AST levels. Presence of anti-HCV and HCV RNA in serum tested at least once during the previous six months. Evidence of chronic hepatitis on liver biopsy done within the previous 12 months with a histology activity index of at least 6 (out of a maximum of 22). Contraindications to the use of alpha interferon, either in the form of specific contraindications to its use (depression, psychiatric illness, neurological impairment, severe thrombocytopenia, autoimmune disease), or the history of severe side effects or intolerance during a previous course of alpha interferon, or lack of a sustained virological (sustained lost of HCV RNA from serum for more than six months after stopping treatment) response to an adequate course (6 months) of the combination of alpha interferon and ribavirin or (after September 1, 2003) the combination of peginterferon and ribavirin. Written informed consent. FOR IN 98-DK-0003: An important group of patients who were enrolled in the current study, were patients who participated in the Clinical Research Protocol 98-DK-0003 (Combination of alpha interferon with long-term ribavirin for patients with chronic hepatitis C) and who did not have a sustained virological response to this treatment. These patients were eligible to enroll into the current study once they had finished the therapy and follow up period in that trial. These patients fit the listed above with one exception: some patients were receiving ribavirin monotherapy as a part of their participation in 98-DK-0003. These patients were eligible to be immediately enrolled into this study without a medication-free period in between  Pregancy or, in women of childbearing potential, inability to practice adequate contraception. Men with spouses or sexual partners of childbearing potential also be excluded if they are unable to practice adequate contraception. Significant systemic illnesses other than liver disease, including a history of congestive heart failure, cerebral vascular disease, renal failure (creatinine clearance less than 50 ml/min), and angina pectoris. Patients with an abnormal stress test or carotid untrasound will not be enrolled into this study. Pre-existing anemia (hematocrit less than 32%) or known history of hemolytic anemia. Interferon or immunosuppressive therapy within the last 6 months. Evidence of another form of liver disease in addition to viral hepatitis, such as autoimmune or alcoholic liver disease. Active or recent (within one year) alcohol or drug abuse or psychiatric illness that is likely to interfere with compliance and requirements for safety monitoring during this study