Comparative analysis of treatment outcomes in patients with neuromyelitis optica spectrum disorder using multifaceted endpoints

Background: There is still an unmet need for comparative analyses of available treatment options for neuromyelitis optica spectrum disorder (NMOSD). Objective: We aimed to compare the efficacies of the immunosuppressants most commonly prescribed for patients with NMOSD using multifaceted endpoints. Methods: We conducted a retrospective analysis of treatment outcomes in 138 NMOSD patients treated with azathioprine, mycophenolate mofetil (MMF), or rituximab. The primary outcome measures were the annualized relapse rate (ARR), annualized severe relapse rate, time to first relapse, and time to first severe relapse. Results: A comparison of any relapse among the groups revealed that the azathioprine had a significantly higher risk of relapse relative to the rituximab (hazard ratio: 1.82; 95% CI: 1.1-3.1; p=0.03). A comparison of severe relapse among the groups revealed that the hazard ratios of severe relapse for the azathioprine and MMF relative to the rituximab were 11.66 (95% CI: 2.6-52.3; p=0.001) and 5.96 (95% CI: 1.0-35.1; p=0.048), respectively. The times to first relapse and first severe relapse were also significantly different among the treatment groups Conclusions: The present study showed that reductions in the risks of relapse and severe relapse differed among patients who were initially treated with azathioprine, MMF, and rituximab.