Perampanel as Adjunctive Therapy in Pediatrics With Partial Onset Seizures or Primary Generalized Tonic Clonic Seizures

Inclusion Criteria: * Have a diagnosis of epilepsy with POS with or without secondarily generalized (SG) seizures or PGTC seizures according to the International League Against Epilepsy's (ILAE) Classification of Epileptic Seizures (1981). A diagnosis should have been established at least 6 months prior to Visit 1 by clinical history and an electroencephalogram (EEG) that is consistent with the diagnosis; normal interictal EEGs will be allowed provided that the participant meets the other diagnosis criterion (that is, clinical history) * Male or female participant, from age 4 to \<12 years at the time of informed consent/assent * Have a minimum weight of 16 kilograms (kg) (35 pounds \[lb\]) * Have had a brain imaging (example, magnetic resonance imaging \[MRI\] scan or computed tomography \[CT\] before Visit 1 that ruled out a progressive cause of epilepsy) * During the 12 weeks +/- 3 days (4 weeks +/- 3 days in Japan only) prior to Visit 2, participants must have equal or greater than (=\>) one POS or one PGTC seizure. Only simple POS with motor signs, complex POS, and complex POS with secondary generalization are counted toward this inclusion for POS * Are currently being treated with stable doses of 1 to a maximum of 3 approved antiepileptic drugs (AEDs). Doses must be stable for at least 4 weeks before to Visit 1; in the case where a new AED regimen has been initiated for a participant, the dose must be stable for at least 8 weeks prior to Visit 1. Only one EIAED (define…