A Randomized, Controlled Trial of Ganaxolone in Adult Uncontrolled Partial-Onset Seizures

INCLUSION CRITERIA: * Diagnosis of epilepsy with POS with or without secondary generalized seizures according to the International League Against Epilepsy \[ILAE\] Classification of Epileptic Seizures (1981). Diagnosis should have been established by clinical history and CT or MRI of the brain to rule out progressive structural lesions and EEG with results consistent with partial-onset epilepsy. * During the 8 week baseline period preceding randomization visit (Visit 4), participants should have a documented seizure frequency of ≥ 3CPS per 4 weeks on average. * Participants should not be seizure free for more than 28 consecutive days during treatment with a stable dose of AEDs \[Note: Participants with historically sufficiently high seizure frequency who fall short 1 seizure in any 4 weeks period or with a seizure-free period \> 28 consecutive days may be allowed to enter the study after discussion with the Medical Monitor. Prolongation of the screening period for questionable cases may also be allowed by the Medical Monitor.\] * Treatment with a stable dose of up to 3 (FDA approved) current AEDs for 1 month prior to screening. * Maintenance of current AEDs without a change in dosing for the duration of study. * Concomitant vigabatrin not permitted; * Felbamate is allowed if the participant has been on felbamate for at least 18 months and has stable laboratory tests) for the course of the study. \[Note: A shorter period for stable laboratory results may be allowed by th…