Neutralizing antibodies in patients with chronic hepatitis C infection treated with (Peg)-interferon/ribavirin

BackgroundThe role of neutralizing antibody (NAb) in determining response to antiviral therapy has not been established.ObjectiveIn this study we have analysed the kinetic's of the NAb response in patients with chronic hepatitis C who received antiviral therapy.Study designSeventeen patients infected with genotype 1, 2a/c or 3a hepatitis C virus (HCV) were enrolled, eight with a sustained virological response (SVR), five non-responders and four relapsers.ResultsThe mean NAb titre required to neutralize 50% of the E1E2-pp in patients who achieved an SVR (294 ± S.D. 51), in relapsers (246 ± S.D. 61.7) and non-responders (286 ± S.D. 80.95) did not differ significantly between the patient groups and did not alter during the course of treatment (P > 0.01). Genetic variation present before antiviral therapy was analysed by single strand conformation polymorphism (SSCP) and failed to demonstrate a significant difference in the mean number of amplified E1E2 DNA fragments from the serum of patients who achieved an SVR (3.15 ± S.D. 1.53), relapsers (2.8 ± S.D. 1.32) or non-responders (3.69 ± S.D. 1.75). The baseline serum HCV viral loads were also not significantly different between patients who achieved an SVR (1.4 × 106 copies/ml; ±S.D. 2.4 × 106), relapsers (1.3 × 107 copies/ml; ±S.D. 2.4 × 107) and non-responders (1.5 × 106 copies/ml; ±S.D. 1.1 × 106).ConclusionWe have shown that neutralizing anti-HCVpp antibody is not associated with response to antiviral therapy. In addition, there was no correlation between baseline virological load, circulating viral quasispecies, NAb titres and final response to treatment.