Efficacy and safety of riluzole for treating motor function in rare dyskinesia syndromes: a systematic review with meta-analysis.

Objectives: We conducted a systematic review and meta-analysis to evaluate the clinical effectiveness and safety of riluzole to treat neurodegenerative dyskinesia in patients, using the Cochrane collaboration guidelines.

Methods: We searched databases including Medline, Embase, and Cochrane without any language filters. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was used as a guideline, and the study protocol was registered in PROSPERO (CRD42022354627).

Results: Eleven studies involving 1376 patients were included. There was a significant overall effect of riluzole on changes in motor function scores. However, the level of heterogeneity was  = 74%. In the subgroup analyses, there were no significant effects of riluzole on motor scores in hereditary ataxia, Parkinson's disease, or Huntington's disease. In the sensitivity analysis, there were no significant effects of riluzole on motor function scores. Furthermore, there were no significant differences in adverse events between the riluzole and placebo groups.

Conclusions: Although riluzole may not have significant efficacy for improving motor function in neurodegenerative dyskinesia syndromes compared with placebo, it seems to have an acceptable safety profile. Moreover, it may be effective for hereditary ataxia syndromes, although there was a relatively small effect size and limited quality of evidence.