Detection of hepatitis C virus RNA in patients with chronic hepatitis C virus infections during and after therapy with alpha interferon

In 24 patients with hepatitic C virus (HCV) infection who participated in a randomized trial with alpha 2B interferon, HCV RNA analysis by the polymerase chain reaction with two separate primer sets was performed at weeks 0, 4, and 24 and during a follow-up period of 6 to 9 months. Prior to therapy all patients were HCV RNA positive. During therapy, HCV RNA decreased to an undetectable level (< 1 chimpanzee infectious dose per ml) in nine patients at week 4. After week 4, no additional cases of HCV RNA disappearance (< 1 chimpanzee infectious dose per ml) were observed. During follow-up, HCV RNA could not be detected in four of the six patients with a sustained alanine aminotransferase response. These results suggest the probable predictive value of HCV RNA levels for detecting the failure of therapy in an early stage of HCV infection.