Prognosis After Discontinuation of Azathioprine or Mycophenolate Mofetil in Well‐Controlled Myasthenia Gravis: A Retrospective Analysis

ABSTRACT Introduction/Aims Azathioprine (AZA) and mycophenolate mofetil (MMF) are generally used for long periods when treating myasthenia gravis. In well‐controlled patients, discontinuation of AZA/MMF may be a cause for concern because of the possibility of relapse. We aimed to evaluate relapse and relapse‐related parameters after discontinuation of AZA/MMF. Method Patients who had discontinued AZA or MMF monotherapy were retrospectively reviewed. We reviewed relapse, whether in pharmacological remission (PR) or exhibiting minimal manifestations (MM 1), disease duration, duration of AZA/MMF use, and other clinical parameters. Results A total of 32 patients were included who either discontinued AZA ( n = 28) or MMF ( n = 4) treatments. Relapse was detected in 11 (34%). Patients in PR had fewer relapses than those with MM 1 ( p = 0.023). Intravenous immunoglobulin was required in four. All patients who relapsed were stabilized with AZA/MMF. No significant association was found between relapse and age of disease onset, duration of disease, duration of AZA/MMF use, thymectomy status, or maximum Myasthenia Gravis Foundation of America score during active disease. Discussion The results of this study suggest that patients in PR are less likely to relapse compared to those in MM 1. In well‐controlled MG patients, AZA/MMF may be discontinued.