Efficacy of azathioprine on multiple sclerosis new brain lesions evaluated using magnetic resonance imaging.

Background: Azathioprine is an immunosuppressive agent that reduces relapse rates in patients with multiple sclerosis (MS), but its efficacy in suppressing new brain lesions has never been evaluated.

Objective: To evaluate the efficacy of azathioprine therapy on new brain lesion suppression in MS.

Design: Open-label treatment vs baseline study.