Azathioprine in MOGAD

MOG-IgG associated disease (MOGAD) is a rare inflammatory disease of the central nervous system recently described. Initially reported as monophasic, data from incident cohorts suggests that around 50% of adult patients with MOG-Ab may relapse within the first two years of the disease, with most of relapses occurring early after disease onset. No randomized controlled trial has ever been performed and therapeutic guidelines for this disease remain unclear especially after a single event. In short-sized and mainly retrospective study, azathioprine, an immunosuppressant drug, have showed promising results on preventing the risk of relapse in MOGAD patients. The hypothesis is that the initiation of a treatment after a first attack of MOGAD should prevent further relapse and disability accrual. The investigators propose herein the first randomized controlled trial in MOGAD, to evaluate the efficacy of azathioprine to prevent relapses, after a first attack, in a placebo double-blinded design.