The role of neutralizing antibodies to interferon-β as a biomarker of persistent MRI activity in multiple sclerosis: a 7-year observational study

Purpose During interferon-β (IFN-β) therapy, up to 45 % of patients may develop neutralizing antibodies (NAbs), associated with a decreased efficacy of the drug. We investigated in a real-life setting the impact of NAbs on magnetic resonance imaging (MRI) outcomes in a population of 567 IFN-β-treated relapsing-remitting (RR) multiple sclerosis (MS) patients up to 7 years. We also evaluated NAbs’ role as a biomarker of the persistence of MRI disease activity.