The evolution of neutralizing antibodies in multiple sclerosis patients treated with interferon beta-1b

The fate of the neutralizing antibody (NAB) in MS patients treated with interferons remains unclear. We conducted a follow-up survey of NAB titers in 59 long-term treated patients from the London and Vancouver cohorts of the pivotal trial of interferon alpha-1b. NAB were measured with the myxovirus protein A assay and an ELISA, at a mean follow-up that exceeded 8 years. NAB disappeared in the majority of patients.