Monitoring virological responses to interferon-ribavirin and interferon monotherapy of chronic hepatitis C re-treated due to relapse or non-response

Adding the nucleoside analog ribavirin (RBV) to interferon (IFN) for treatm ent of HCV has improved the sustained response rates, but the mechanism by which REV mediates viral clearance is not fully understood. in this study, a highly sensitive method (Codes Amplicor HCV Monitor),vas used to monitor the early (first IZ weeks of therapy) and long-term virological response in 20 patients who were treated first with IFN and later, due to non-sustaine d response, with IFN-RBV. All 10 IFN relapsers displayed a prompt virologic al response at week 4 to both IFN and IFN-RBV therapy; nine of them showed a sustained response to IFN-RBV. Out of 10 IFN non-responders, five showed a sustained response to IFN-RBV. Four of these were I-ICV RNA-negative at w eek 4 of IFN-RBV therapy and two of them had a transient early virological response (RNA-negative at weeks 4-8) to IFN alone. Overall, of the 14 patie nts (nine IFN relapsers, five IFN non-responders) with a sustained response to IFN-RBV, II and 13 had HCV RNA below 2000 copies/ml at week 4 of IFN an d IFN-RBV, respectively, as compared with one and one of six patients witho ut a sustained response to IFN-RBV (p < 0.02). Thus, addition of REV to IFN increased both viral clearance during the first 12 weeks of therapy and th e rate of sustained response. Loss of viremia at week 4 of IFN was associat ed with a sustained response to IFN-RBV and was seen in Ii of 13 patients ( 85%) with genotypes 2 or 3, as compared with one of seven patients (14%) wi th genotype 1 (p = 0.0044).