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

BACKGROUND

A 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.

OBJECTIVE

To assess clinical activity in MS relapsing-remitting (MS RR) patients with high pre-treatment activity who discontinued IFNβ treatment after approximately 2 years of treatment.

METHODS

We determined the relapse rate and disability progression in 43 patients who discontinued IFNβ after ~25 months of treatment.

RESULTS

Within ~34 months post-treatment 28 patients (65%) experienced at least one severe relapse, and 8 MS patients experienced a relapse within 30 days post IFNβ discontinuation. Disability progression measured by EDSS in the post-treatment period was 1.45±0.8 points per patient.

CONCLUSION

These 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.