Interferon for interferon nonresponding and relapsing patients with chronic hepatitis C.

Abstract

Interferon monotherapy leads to sustained virologic clearance in a minority of patients with chronic hepatitis C. Studies have yielded conflicting results regarding retreatment with interferon in nonresponders and relapsers. To assess the beneficial and harmful effects of retreatment with interferon in chronic hepatitis C nonresponders and relapsers to previous interferon treatment. Trials were identified through electronic databases, manual searches, authors, and pharmaceutical companies (August 2001). Randomised trials comparing interferon versus control or different interferon regimens in chronic hepatitis C patients being nonresponders and relapsers to previous interferon were included. The primary outcome was failure to achieve a sustained virologic response defined as positive serum hepatitis C virus RNA at least six months following treatment. Secondary outcomes included liver-related morbidity, mortality, biochemical responses, adverse events, and histology. Ten randomised trials involving 686 nonresponders and eight trials involving 484 relapsers were included; their methodological quality was poor. In nonresponders, interferon reduced the risk of not achieving an end of treatment biochemical response compared with no treatment (relative risk [RR] 0.77, 95% confidence interval [CI] 0.66 to 0.91); however, virologic responses were not reported. In a post hoc subgroup analysis, doses greater than 3 million units (MU) three times weekly offered no advantage compared with 3 MU three times weekly for biochemical sustained response. Failure to obtain a virologic sustained response was less likely with 48 than 24 weeks of therapy (RR 0.87, 95% CI 0.79 to 0.96). Adverse events did not differ significantly regardless of treatment dose or duration. In relapsers, none of the trials compared interferon with no treatment. In a post hoc analysis, doses greater than 3 MU three times weekly were no more effective in achieving a virologic sustained response than 3 MU three times weekly. Compared with 24 weeks, treatment durations of 48 weeks were less likely to fail to achieve a virologic sustained response (RR 0.69, 95% CI Random 0.51 to 0.95), but associated with more frequent dosage reduction (RR 9.07, 95% CI 1.20 to 68.63). No data regarding clinical outcomes or histology was available in either patient group. Retreatment with interferon leads to sustained virologic clearance in a minority of chronic hepatitis C patients with nonresponse or relapse following interferon monotherapy. Treatment durations of 48 weeks are superior to 24 weeks, but doses greater than 3 MU three times weekly are no more effective. No data exists regarding the effect on clinical outcomes.