Analysis of safety and efficacy of pegylated-interferon alpha-2a in hepatitis C virus positive hemodialysis patients: results from a large, multicenter audit.

Background: Hepatitis C virus (HCV) infection rates are still high in hemodialysis (HD) centers in developing countries. Standard interferon (IFN) monotherapy is associated with good results in HCV-positive patients (more than 30% rate of sustained virological response) but with poor tolerance. Pegylated interferon (PEG-IFN) is better tolerated and has a more sustained antiviral effect in the general population. There have been no large trials to date with PEG-IFN in hemodialysis populations.
Methods: We report the largest series to date of HCV+ HD patients (n=78) treated with PEG-IFN alfa -2a 135 microg s.c. weekly monotherapy. The primary outcomes were (a) efficacy - assessed by the viral response at 12, 48 weeks and 6 months after completion of therapy, and (b) rate of serious adverse events.
Results: In 48/78 (61.5%) patients an early (12 weeks) viral response was obtained. Viral end-of-treatment response (ETR) was evaluated in the 21 patients (26.9%) who reached week 48 on therapy: only 15 subjects (19.2% of the initial population) had undetectable HCV-RNA levels. In these 15 patients, a sustained viral response (SVR) was recorded in 11 - i.e. 14.1% of the initial intention-to-treat (ITT) population. A high prevalence of noncompliance (32%) and of adverse events (83%) was recorded; minor adverse effects (flu-like syndrome, mild-to-moderate thrombocytopenia, leukopenia and anemia) responded to symptomatic therapy or dose reduction, but often caused lack of compliance. The incidence rate of serious adverse events was 0.19/patient-year (median time to event 20.5 weeks), and incidence of deaths was 0.11/patient-year.
Conclusions: In dialysis patients, PEG-IFN alfa -2a is poorly tolerated and associated with a high number of serious adverse events, causing a significant lack of compliance/discontinuation of therapy. In this largest HCV-positive hemodialysis population survey, we report a low sustained viral response in an ITT analysis, compared with previously published historical data using non-PEG-IFN, a low compliance rate and an unsatisfactory overall safety profile, not supporting the superiority of PEG-IFN monotherapy.