Azathioprine for multiple sclerosis

Background: Azathioprine (AZA) is an immunosuppressive drug widely prescribed for the treatment of multiple sclerosis (MS) until the first half of the 1990s. It could be an alternative to interferon β because it is less expensive. Concerns about its safety, mainly a possible increased risk of malignancy, have been raised. This systematic review aimed to determine the trade off between the benefits and risks of azathioprine in MS. Objectives: To compare azathioprine with placebo. To assess the effect of azathioprine on major clinical outcomes (ie, disability progression and relapses) in patients with MS, and to evaluate the drug's safety. Methods: The Cochrane MS Group search strategy was adopted to identify relevant articles. All randomised controlled trials comparing azathioprine treatment of a least 1 year duration with placebo for patients with MS were eligible for the review. Cohorts, case controls, case series and case reports were also considered to assess adverse effects. Regulatory agencies were additional sources of information for adverse effects. More details are available in the full review.