Perampanel, an AMPA antagonist, found to have no benefit in reducing “off” time in Parkinson's disease§


  • Funding agencies: These studies were funded by Eisai Inc.

  • Relevant conflicts of interest/financial disclosures: All authors received compensation from Eisai for their site's conduct of the study and/or as members of steering committees. Joseph Jankovic has received honoraria as a consultant to Eisai. Anthony Lang, M. Maral Mouradian, Olivier Rascol, and C. Warren Olanow have served as advisers or consultants for Eisai. David Squillacote and Dinesh Kumar are employed by Eisai.

  • §

    Full financial disclosures and author roles may be found in the online version of this article.



Perampanel is a selective, noncompetitive α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor antagonist. Two multicenter randomized, double-blind, placebo-controlled, parallel-group phase III studies assessed the efficacy and safety of adjunctive perampanel in patients with Parkinson's disease and motor fluctuations.


In both phase III studies (301 and 302), levodopa-treated patients were randomized and treated with once-daily oral placebo (n = 504), perampanel 2 mg (n = 509), or perampanel 4 mg (n = 501). The primary end point was change in daily “off” time from baseline. The treatment period was 30 weeks in study 301 and 20 weeks in study 302.


For any efficacy end point, perampanel 2 or 4 mg was not superior to placebo. Perampanel was well tolerated up to 4 mg/day.


Perampanel failed to significantly improve motor symptoms versus placebo. There was also no effect on the duration or disability of levodopa-induced dyskinesia. © 2011 Movement Disorder Society