Interferon for acute hepatitis C.

Background: Acute hepatitis C virus (HCV) infection progresses to chronicity in the majority of patients. In order to prevent the progression to chronic disease, several studies have assessed interferon in patients with acute hepatitis C.

Objectives: The aim of this review was to assess the efficacy of interferon in acute HCV infection.

Search Strategy: We searched MEDLINE, the Cochrane Controlled Trials Register, and the abstracts of the American Association for the Study of Liver Diseases (June 2001). We also contacted pharmaceutical companies to obtain unpublished trials.

Selection Criteria: Randomised clinical trials comparing interferon with placebo or no treatment, and published as an article, abstract, or letter were selected. No language limitations were used.

Data Collection And Analysis: Two reviewers independently assessed trial quality and extracted data. The following endpoints were analysed: normalization of alanine aminotransferase (ALT) activity at the end of treatment (biochemical ETR); sustained ALT normalization at the end follow-up (biochemical SR); disappearance of serum HCV RNA by polymerase chain reaction assay at the end of treatment (virologic ETR) and at the end of follow-up (virologic SR). Histologic data and adverse events were also recorded. Assessment of drug efficacy used the methods of Peto and Der Simonian and Laird.

Main Results: Six randomised trials involving 206 patients with acute hepatitis C met the inclusion criteria. Four trials assessing interferon alfa-2b in 141 patients, all with transfusion-acquired acute hepatitis C, were included. They demonstrated no significant heterogeneity in the outcomes assessed. When compared with no treatment, interferon alfa-2b was associated with an increase in the rates of virologic ETR and SR by 45% (95% CI 31-59%, P < 0.00001) and 29% (95% CI 14-44%, P = 0.0002), respectively. The virologic ETR was 42% (95% CI: 30-56%) in the interferon alfa-2b group versus 4% (95% CI 0-13%, P < 0.00001) in the control group. At the end of follow-up, a virologic SR was seen in 32% (95% CI 21-46%) of interferon-treated patients versus only 4% (95% CI 0-13%, P = 0.00007) of controls. The tolerability of therapy, or the impact of interferon alfa-2b on hepatic histology, was not reported. Two trials assessed interferon beta in a total 65 patients. The efficacy of interferon beta could not be assessed, however, due to heterogeneity of these trials.

Reviewer's Conclusions: Interferon alfa is effective in improving biochemical outcomes and achieving sustained virologic clearance in patients with transfusion-acquired acute hepatitis C. The effect on long-term clinical outcomes could not be assessed due to limitations in the current data.