Optimization of the safety and efficacy of interferon beta 1b and azathioprine combination therapy in multiple sclerosis

Abstract

We conducted an open-label pilot clinical trial to evaluate the safety and efficacy of adding oral azathioprine to the treatment regimen of 15 multiple sclerosis patients breaking through monotherapy with interferon β-1b. There were no serious adverse events. Gastrointestinal side effects and leukopenia were the most common adverse events and limited dose escalation. There was a 65% reduction in the number of gadolinium-enhanced magnetic resonance imaging (MRI) lesions on combination therapy compared to the baseline values (P=0.003). A total WBC count less than 4800/mm³ was the best predictor of MRI response.

Keywords

immunosuppression MRI therapy 6-thioguanine toxicity

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