Should clinical trials of disease-modifying therapies be conducted for neuromyelitis optica (NMO)? If so, how should these trials be designed and which therapy tested? Because of its relative scarcity as well as the clinical overlap with multiple sclerosis (MS), randomized clinical trials of NMO treatments have not been undertaken. Hence, there are no therapies that are proved to reduce the frequency of relapses in NMO and alleviate the accumulation of disability. Open-label studies suggested that immune suppressants, such as azathioprine (AZA),1 rituximab,2 and mycophenolate mofetil (MMF),3 may reduce the frequency of relapses in NMO. In this issue, Huh and colleagues4 report their experience treating 58 patients with NMO using MMF. To my knowledge, this is the largest study of MMF treatment in patients with NMO reported thus far. Huh and colleagues observed that, following MMF treatment, there was a decline in the annualized relapse rate and that disability, as measured by the Expanded Disability Status Scale (EDSS), improved. In particular, this study suggests efficacy of MMF in patients with NMO who have not been treated with other immune therapies. This study also suggests that treatment with MMF is associated with fewer adverse effects than AZA, a widely used, broad-spectrum immune suppressant. These observations complement and add to the existing publications of similar uncontrolled, open-label studies, suggesting the therapeutic efficacy of immune suppressants in treating NMO.
Cree B. Mycophenolate Mofetil to Treat Neuromyelitis OpticaIs It Time for a Randomized Trial?. JAMA Neurol. 2014;71(11):1354-1357. doi:10.1001/jamaneurol.2014.2359