Time to exceed pre‐randomization monthly seizure count for perampanel in participants with primary generalized tonic–clonic seizures: A potential clinical end point

Objective To evaluate the exploratory time to exceed pre‐randomization seizure count (T‐PSC) in the determination of efficacy of adjunctive perampanel in participants with primary generalized tonic–clonic (PGTC) seizures in generalized‐onset epilepsy. Methods In this multicenter, double‐blind study (ClinicalTrials.gov identifier: NCT01393743), participants ≥12 years of age with treatment‐resistant idiopathic generalized epilepsy were randomized to receive placebo or adjunctive perampanel (≤8 mg/day) across a 17‐week double‐blind treatment phase (4‐week titration; 13‐week maintenance). We evaluated the pre‐planned exploratory end point of the T‐PSC using a Kaplan–Meier analysis. We also re‐evaluated the correspondence of the primary end points of median percent seizure frequency change (MPC) and 50% responder rate (50RR) calculated at T‐PSC and at the end of the trial. Results The exploratory end point of median T‐PSC on placebo was 43 days and >120 days on perampanel (log‐rank p