Perampanel: a novel antiepileptic for the adjunctive treatment of refractory partial onset seizures.

Perampanel is a selective noncompetitive AMPA-type glutamate receptor antagonist which has demonstrated anticonvulsant activity in experimental seizure models and antiepileptic activity in clinical trials. Perampanel has a long mean elimination half-life of 105 hours but this may be reduced in the presence of enzyme-inducing antiepileptic drugs. Adjunctive use of perampanel at 4-12 mg/day in refractory partial-onset seizures reduced seizures by 23-34% in short-term, double-blind, placebo-controlled trials. These reductions were maintained long-term in open-label extension studies lasting up to 4 years. Dizziness, somnolence and headache were the most common treatment-emergent adverse events; discontinuation rates due to adverse events approximated 13% in long-term studies. Perampanel's efficacy and tolerability outcomes are broadly comparable with other agents licensed for adjunctive use in refractory partial onset seizures.