A systematic review and meta-analysis did not find enough evidence to support the use of memantine in patients with multiple sclerosis (MS) to reduce fatigue, control spasticity, and prevent cognitive decline or disability.
The researchers queried Medline, the Cochrane Controlled Register of Trials, Scopus, Embase, Literatura Latino-Americana e do Caribe em Ciências da Saúde, ClinicalTrials.gov, and the Health Research and Development Information Network for relevant randomized trials published through May 2020. Study designs including quasi-experimental, cluster-randomized, crossover, prospective or retrospective cohort, case–control, and cross-sectional designs were excluded.
Of 203 total articles identified, four were included in the qualitative and quantitative syntheses; all trials were double-blind, randomized, placebo-controlled studies. Collectively, the four studies included 285 patients with MS, of whom 145 received memantine (treatment group) and 140 received placebo (control group). The mean age in the treatment group was 43.85 years and 45.28 years in the control group; both groups were roughly three-quarters female. Mean disease duration was 11.47 years and 10.83 years, respectively, and the most primary MS subtype was relapsing/remitting (74% and 84%, respectively).
One study evaluated the efficacy of memantine on fatigue. There were no significant differences in mean change from baseline Modified Fatigue Impact Scale scores (between-group difference, –1.9; 95% confidence interval, –11.7 to 7.8; P=0.702).
Memantine was associated with mild adverse drug events but was considered generally safe for patients with MS.
“Further research investigating the different MS clinical subtypes, role of co-administration of memantine with disease-modifying therapies, longer duration of administration, and more unified and sensitive outcome measures are needed to evaluate the potential benefit of memantine among patients with MS,” the study authors concluded.