Efficacy of interferon monotherapy in the treatment of relapsers and nonresponders with chronic hepatitis C infection.

Results of numerous studies have demonstrated similar efficacy profiles for the interferons (IFNs) currently approved for the treatment of chronic hepatitis C virus (HCV) infection. Although it has been suggested that some IFNs are more efficacious in certain patient populations, the current data support an equivalent efficacy and safety profile for these agents. Among patients requiring retreatment, no single study has made a direct comparison of IFN alfa-2b (IFN-alpha 2b) and consensus IFN (CIFN) in patients who have relapsed or have not responded to previous IFN therapy. However, at least 11 studies using IFN-alpha 2b and 1 using CIFN have demonstrated efficacy in the relapsing and nonresponding patient populations. A review of these studies suggests that overall efficacy and tolerability are similar regardless of IFN-alpha subtype. Overall, up to 59% and 83% of relapsed patients retreated with IFN have shown sustained response rates, as measured by negative HCV RNA titer and normalization of alanine aminotransferase (ALT) levels, respectively. Up to 14% and 25% of patients who failed to respond to previous IFN therapy have shown sustained HCV RNA response and normalization of ALT, respectively, after retreatment.