<qa>  What is the study of perampanel as adjunctive therapy?This is a multicenter, double-blind, randomized, placebo-controlled, parallel-group study of perampanel as adjunctive therapy in participants with inadequately controlled seizures associated with LGS. The study will consist of 3 phases: Prerandomization 4 to 8 weeks, Randomization 22 weeks, and Extension 56 weeks. 