Decrease in serum hepatitis C viral RNA during alpha-interferon therapy for chronic hepatitis C

Abstract

Objective: To assess the effect of alpha-interferon therapy on hepatitis C viral RNA in serum of patients with chronic hepatitis C.

Design: Retrospective testing for hepatitis C viral (HCV) RNA and antibody to the hepatitis C virus (anti-HCV) of stored serum samples from a randomized, double-blind, placebo-controlled trial of alpha-interferon therapy.

Setting: Warren Grant Magnuson Clinical Center of the National Institutes of Health, a tertiary referral center.

Patients: Forty-one patients with chronic non-A, non-B hepatitis were entered in this trial.

Interventions: Twenty-one patients were treated with alpha-interferon, and 20 patients were treated with placebo for 6 months. Seventeen placebo recipients were then treated with alpha-interferon for up to 1 year.

Methods: Samples were tested for anti-HCV by enzyme-linked immunosorbent assay. Hepatitis C viral RNA was detected in serum using the polymerase chain reaction. Titers of both antibody and RNA were determined by serial end-point dilution.

Main results: At entry into the trial, 37 (90%) of 41 patients had anti-HCV and 39 (95%) had HCV RNA in serum. Anti-HCV titers decreased slightly with treatment. Serum levels of HCV RNA decreased in all patients who responded to alpha-interferon therapy with improvements in serum aminotransferases; in 17 of 21 responders (81%; 95% Cl, 58% to 95%) HCV RNA became undetectable. In contrast, in only 2 of 16 (12%; Cl, 2% to 38%) patients who did not respond to treatment did HCV RNA become undetectable. In 19 patients treated during the preliminary 6-month period with placebo, HCV RNA remained detectable. Finally, in the 11 patients who relapsed when treatment was stopped, HCV RNA reappeared in the serum, but in 4 of 7 patients with a sustained improvement in serum aminotransferases, HCV RNA remained undetectable.

Conclusions: These results indicate that the clinical and serum biochemical response to alpha-interferon in chronic hepatitis C is associated with a loss of detectable HCV genome from serum.