Evaluating Efficacy and Safety of E2007 (Perampanel) Given as Adjunctive Therapy in Subjects With Refractory Partial Seizures

Inclusion Criteria

• Provide written informed consent signed by the subject or legal guardian prior to entering the study or undergoing any study procedures (If the written informed consent is provided by the legal guardian because the subject is unable to do so, a written or verbal assent from the subject must also be obtained.).
• Be considered reliable and willing to be available for the study period and able to record seizures and report AEs them self or have a caregiver who can record seizures and report AEs for them;
• Male or female and greater than or equal to 12 years of age (within the course of the study), or greater than or equal to 18 years of age (depending on location) at the time of signing the informed consent.
• Females should be either of non-childbearing potential (defined as having undergone surgical sterilization, or postmenopausal [age 50 and amenorrheic for 12 months]) or of childbearing potential. Females of childbearing potential must have a negative serum beta-human chorionic gonadotropin (ß-hCG) at Visit 1 and a negative urine pregnancy test prior to randomization at Visit 2. Female subjects of childbearing potential must agree to be abstinent or to use at least 1 medically acceptable methods of contraception (eg, a double-barrier method [eg, condom + spermicide, condom + diaphragm with spermicide], IUD, or have a vasectomised partner) starting at Visit 1 and throughout the entire study period and for 2 months after the last dose of study drug. Those women using hormonal contraceptives must also be using an additional approved method of contraception (as described previously) starting at Visit 1 and continuing throughout the entire study period and for 2 months after the last dose of study drug. (It is not required for male subjects to use contraceptive measures based on preclinical toxicology data.);
• Have a diagnosis of epilepsy with partial seizures with or without secondarily generalized seizures according to the International League Against Epilepsy's Classification of Epileptic Seizures (1981). Diagnosis should have been established by clinical history and an electroencephalogram (EEG) that is consistent with localization-related epilepsy; normal interictal EEGs will be allowed provided that the subject meets the other diagnosis criterion (ie, clinical history);
• Have had a computed tomography (CT) or magnetic resonance imaging (MRI) within the last 10 years that ruled out a progressive cause of epilepsy;
• Have uncontrolled partial seizures despite having been treated with at least 2 different anti-epileptic drugs (AEDs) within approximately the last 2 years;
• During the 6-week Pre-randomization Phase subjects must have had >/= 5 partial seizures per 6-week (with >/=2 partial seizures per each of 3-week period) and with no 25-day seizure-free period in the 6-week period, as documented via a valid seizure diary. Only simple partial seizures with motor signs, complex partial seizures, and complex partial seizures with secondary generalization are counted toward this inclusion;
• Are currently being treated with stable doses of 1, 2 or a maximum of 3 approved AEDs. Only 1 inducer AED (defined as; carbamazepine, phenytoin, phenobarbital, or primidone only) out of the maximum of 3 AEDs is allowed;
• Are on a stable dose of the same concomitant AED(s) for 1 month (or no less than 21 days) prior to Visit 1; in the case where a new AED regime has been initiated for a subject, the dose must be stable for 2 months (or no less than 49 days) prior to Visit 1;
• If on a stable dose (other than intermittent rescue use) of benzodiazepines for epilepsy (or for anxiety or sleep disorders) the prescribed dose must be stable for 1 month (or no less than 21 days) prior to Visit 1. (Note: the use of intermittent rescue benzodiazepines is defined in the exclusion criterion #22 below.) When used in these cases (epilepsy, anxiety or sleep disorders), benzodiazepines will be counted as 1 AED; theref