A 40-week phase 2B randomized, multicenter, double-blind, placebo-controlled study evaluating the safety and efficacy of memantine in amyotrophic lateral sclerosis.

introductionAmyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disease with no known cure, limited treatment options with minimal benefits, and significant unmet need for disease modifying therapies.

aimsThis study investigated memantine's impact on ALS progression, with an additional focus on the effects of memantine on cognitive and behavioral changes associated with the disease.

methodsA randomized, double-blind, placebo-controlled clinical trial was conducted from December 2018 to September 2020. ALS patients were enrolled in-person and remotely across 13 sites in the United States. Participants were randomized to memantine (20 mg twice daily) or placebo in a 2:1 ratio and completed 36 weeks of treatment. The primary outcome of disease progression was assessed by the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R), and blood was collected for biomarker analysis.

resultsOf the 99 participants enrolled in the study, 89 were randomized to memantine or placebo (ages 24-83 years, male-to-female ratio ~3:2). Fifty-two participants completed the study treatment with no significant differences in disease progression, biomarker changes (including neurofilament light chain [NfL]), or neuropsychiatric testing noted between the groups. Initial NfL values correlated with the rate of ALSFRS-R decline. DISCUSSION: In this study, memantine did not impact ALS disease progression or neuropsychiatric symptoms. Trials with remote enrollment may help trial participation and success.