Long-term effect of HCV eradication in patients with mixed cryoglobulinemia: A prospective, controlled, open-label, cohort study.

Limited data are available about the efficacy of antiviral treatment in hepatitis C virus (HCV)-associated mixed cryoglobulinemia (MC), especially concerning the long-term effects of HCV eradication. The aim of this study was to evaluate the influence of MC on the virological response and the long-term effects of viral eradication on MC. We prospectively enrolled 424 HCV+ patients belonging to the following groups: MCS-HCV (121 patients with symptomatic MC); MC-HCV (132 patients with asymptomatic MC); HCV group (158 patients without MC). Peg-IFN+RBV treatment was administered according to standard protocols. Post-treatment follow-up ranged from 35 to 124 months (mean: 92.5 months). A significant difference was observed in the rate of sustained virological response (SVR) between HCV and both MC-HCV (p=0.009) and MC-HCV+MCS-HCV (p=0.014) groups. Multivariate logistic regression analysis identified cryoglobulinemia as an independent prognostic factor of non-response. The clinical-immunological response in MCS-HCV correlated with the virological one. All patients with SVR also experienced a sustained clinical response, either complete or partial. In the majority of SVR patients all MCS symptoms persistently disappeared (36 patients, 57%); in only 2 (3%) did definite MCS persist. All virological non-responders were also clinical non-responders, in spite of a transient improvement in some cases. No evolution to lymphoma was observed. For the first time we have evaluated both the effects of IFN-based therapy on HCV patients with or without MC, and with or without symptoms, and the long-term effects of viral eradication on MC. MC was shown to be a negative prognostic factor of virological response. HCV clearance led to persistent resolution or improvement of MC syndrome, strongly suggesting the need for a next generation of highly effective antiviral drugs.