TREATMENT WITH RECOMBINANT INTERFERON-ALPHA-2A FOR PATIENTS WITH CHRONIC HEPATITIS-C - PREDICTIVE FACTORS FOR BIOCHEMICAL AND VIROLOGICAL RESPONSE

Background: The heterogeneity of the hepatitis C virus (HCV) genome ha s been reported to be associated with the effectiveness of interferon therapy. We investigated the correlation of the viral and host factors , including the degree of sequence complexity of the HCV genome for re sponses to interferon-a In patients with chronic hepatitis C. Methods: Ninety-seven patients received a 26-week course of recombinant interf eron-alpha 2a therapy. The sequence complexity of the envelope 1-2 reg ion was evaluated by polymerase chain reaction-mediated single-strand conformation polymorphism (PCR-SSCP) analysis. Results: of the 85 pati ents who completed the treatment, 31 (36%) achieved a sustained respon se, and 28 (33%) showed a sustained loss of HCV RNA. A low HCV RNA lev el, determined by the branched DNA probe assay, and serotype group 2 H CV correlated with a sustained response. In patients with serotype gro up 1 HCV of more than the threshold of the branched DNA probe assay, a band number on PCR-SSCP analysis of more than 2 could be associated w ith inefficacy of interferon therapy. Multivariate analysis in the 50 patients whose sera were available for all the virologic tests showed that only the HCV RNA level is independently predictive of a sustained response. Conclusions: Determination of the HCV RNA level is most imp ortant for predicting the response before interferon therapy. PCR-SSCP analysis may be useful as an additional test for patients with a high HCV RNA level of serotype group 1 HCV.