Discontinuation of interferon beta therapy in multiple sclerosis patients with high pre-treatment disease activity leads to prompt return to previous disease activity

Abstract

BackgroundA recommendation for the duration of interferon beta (IFNβ) treatment in multiple sclerosis (MS) patients with a good response to this therapy has not been defined. Very limited data exist with regard to the effect of IFNβ discontinuation on the subsequent course of MS. ObjectiveTo assess clinical activity in MS relapsing–remitting (MS RR) patients with high pre-treatment activity who discontinued IFNβ treatment after approximately 2years of treatment. MethodsWe determined the relapse rate and disability progression in 43 patients who discontinued IFNβ after ~25months of treatment. ResultsWithin ~34months post-treatment 28 patients (65%) experienced at least one severe relapse, and 8 MS patients experienced a relapse within 30days post IFNβ discontinuation. Disability progression measured by EDSS in the post-treatment period was 1.45±0.8 points per patient. ConclusionThese results indicate that IFNβ did not induce a prolonged remission in MS patients and that disease activity returned to the previous rate within a short time after treatment cessation. Discontinuation of IFNβ treatment in high activity pre-treatment MS patients with good response to this therapy is not recommended.