Methotrexate is effective for the treatment of neuromyelitis optica spectrum disorders in Asian patients

Abstract

Background Immunosuppression is effective in the secondary prevention of neuromyelitis optica spectrum disorder (NMOSD) relapse. However, some of the newer immunosuppressive agents are costly or unavailable in resource-poor countries; older immunosuppressive agents might be just as effective. We aimed to evaluate the efficacy and tolerability of methotrexate in treating NMOSD in an Asian cohort. Methods We retrospectively reviewed all patients with NMOSD treated with methotrexate at the National Neuroscience Institute, Singapore, between 1992 and September 2012. We compared the annualized relapse rates and disability as measured by the Expanded Disability Status Scale before and after methotrexate treatment. Results Eight of 180 patients with central nervous system demyelinating diseases fulfilled the inclusion criteria. At median follow up of 53 months (range 42-70 months), the median post-treatment annualized relapse rate was significantly lower than the pretreatment rate (0.00 [range 0.00-3.09] vs 0.97 [range 0.08-10.14] relapses). The median Expanded Disability Status Scale remained stable (pretreatment 6.5 [range 3.0-8.0] vs post-treatment 6.0 [range 2.0-8.0], P = 0.238); 75% of our cohort remained relapse-free on treatment. None of our patients were intolerant of methotrexate. Conclusions Methotrexate is well-tolerated in our NMOSD patients, and appears to be effective in decreasing relapse rates and preventing disability progression. It is widely available and less costly than newer immunomodulatory agents. As such, it can be recommended as a therapeutic option for NMOSD in patients who fail first-line therapy.