Does BRV Have Faster Onset Time & Greater Effect Than LEV in Epilepsy Pts Using PPR Pharmacodynamic Efficacy Endpoint

Single dose intravenous administration of BRV 100 mg over a 15 minutes period. On a subsequent occasion, (approximately 2 weeks later), the patient is crossed over to the other drug at a singular dose. On both occasions, intermittent photic stimulation is done 10 times in a two hour period. IPS is again conducted in the cross over portion as well. Coincident with IPS stimulation 10 blood samples will be drawn for BRV or LEV plasma concentration.