Usefulness of interferon for treatment of hepatitis C

The integrated results of a worldwide clinical research program studying interferon-alpha 2a (IFN-alpha 2a) (Roferon-A, F. Hoffmann-La Roche Ltd, Basel, Switzerland) for the treatment of chronic hepatitis C in 1831 patients are reviewed in this paper. According to a multivariate analysis of the data available from this extensive program, which studied fixed, escalating, and deescalating dose regimens of 1, 3, 4.5, and 6 million international units (MIU) for 3, 6 and 12 months in 10 clinical trials, the best response rates were obtained with an induction dose of 6 MIU given thrice weekly for 3 months, followed, in responding patients, by a maintenance regimen of 3 MIU thrice weekly for an additional 3 months. Before the decision to treat is taken, a careful assessment of individual patients' clinical history and prognosis based on stage and activity of their chronic hepatitis and associated other diseases must be made and weighed against the statistical odds of treatment success. Liver histology and repeated measurements of biochemical markers of liver disease such as alanine transpeptidase (ALT) are classical indicators. More recently, quantitative assessment of viremia has become possible with the polymerase chain reaction (PCR) to measure the number of viral genomes per milliliter of serum. After the decision to treat, monthly monitoring of those markers gives a dynamic picture of the therapeutic effect. Depending on the course observed, the indication for the treatment must be reevaluated after induction therapy. Responding patients should receive an additional 3 months of maintenance therapy. If a patient shows no satisfactory evidence of response, treatment must be discontinued.