YKP3089C025: A Randomized, Double-blind, Placebo-controlled, Multicenter Study to Evaluate the Efficacy and Safety of Cenobamate Adjunctive Therapy in Subjects with Primary Generalized Tonic-Clonic Seizures

The primary and secondary outcomes are This is a Phase 3, global, randomised, double-blind, placebo-controlled study evaluating the efficacy and safety of Cenobamate adjunctive therapy in children and adults with Primary Generalised Tonic-Clonic (PGTC) seizures. The study consists of a 12-week pre-randomisation period followed by a 22-week double-blind treatment period, which comprises of a 10-week titration and 12-week maintenance phase. Participants who complete the double-blind treatment period will be offered enrolment in the open-label extension (OLE) study. Participants who do not enrol in the OLE study will enter a 3-week follow up period. To be suitable for the study, participants must be aged 12 years or older, have a clinical diagnosis of PGTC seizures in the setting of idiopathic generalised epilepsy and experience at least 5 PGTC seizures during the 12-week pre-randomisation period. The primary objective of the study is to demonstrate the efficacy of adjunctive cenobamate 200mg (or the adolescent equivalent dose) compared with placebo on PGTC seizures in participants aged 12 years or older.