Long-term efficacy of mycophenolate mofetil in myelin oligodendrocyte glycoprotein antibody-associated disorders: A prospective study.

Objective To investigate whether the use of mycophenolate mofetil (MMF) could reduce the relapse risk in patients with myelin oligodendrocyte glycoprotein (MOG)-immunoglobulin G (IgG)-associated disorders (MOGADs). Methods This prospective observational cohort study included patients with MOGAD at Peking Union Medical College Hospital between January 1, 2017, and April 30, 2019. The patients were divided into 2 groups: those with (MMF+) or without (MMF−) MMF therapy. The primary outcome was relapse at follow-up. We used Cox proportional hazards models to calculate hazard ratios (HRs) for relapse. Results Seventy-nine patients were included in our MOG cohort. Fifty (63.3%) were adults at index date, and 47 (59.5%) were women. Fifty-four (68.4%) were in the MMF+ group, and 25 (31.6%) were in the MMF− group. Clinical and demographic factors, MOG-IgG titer, and follow-up time (median, 472.5 days for MMF+, 261.0 days for MMF−) were comparable between the groups. Relapse rates were 7.4% (4/54) in the MMF+ group and 44.0% (11/25) in the MMF− group. Of all potential confounders, only the use of MMF was associated with reduced risk of relapse. The HR for relapse among patients in the MMF+ group was 0.14 (95% CI, 0.05–0.45) and was 0.08 (95% CI, 0.02–0.28) in a model adjusted for age, sex, disease course, and MOG-IgG titer. MMF therapy also remained associated with a reduced relapse risk in sensitivity analyses. Only one patient (1.9%) discontinued MMF therapy because of adverse effect. Conclusions These findings provide a clinical evidence that MMF immunosuppression therapy may prevent relapse in patients with MOGAD. Classification of evidence This study provides class IV evidence that for patients with MOGAD, MMF reduces relapse risk.