Antiviral therapy for chronic hepatitis C viral infection.

Hepatitis C affects at least 200 million people worldwide. It can be followed by chronic hepatitis, cirrhosis, and primary liver cancer. Outcome assessments in controlled trials of antiviral therapy are based on serum transaminase values, serum HCV-RNA determinations, and liver biopsy scores. Patients most likely to respond to antiviral treatment are relatively young, have low serum HCV-RNA and transaminase levels, and do not have cirrhosis. Patients whose disease is caused by genotype 1b HCV isolates are unlikely to respond. Interferon alfa (3 million units [MU] three times a week for 6 months) is associated with a 50% response rate and a 50% relapse rate--an overall response rate of 25%. Increasing the duration of therapy may increase the sustained response rate. Ribavirin, given orally, may be used for patients who fail to respond to or relapse after interferon therapy. Its side effects are few. Treatment results in a fall in transaminase levels and some decrease in hepatic inflammation, but serum HCV RNA (viral titer) is unaltered. Combinations of interferon with ribavirin are giving promising results with increased sustained, complete responses.