Phase 3 Study of Adjunctive Ganaxolone in Adults With Drug-resistant Partial Onset Seizures and Open-label Extension

Inclusion Criteria: * Able to give informed consent in writing, or have a legally authorized representative able to do so * Willing to enter and participate for the full term of the double blind phase and willing to enter into the open-label phase * Male or female outpatients \> 18 years of age * Have a confident diagnosis of drug-resistant epilepsy with partial-onset seizures (POS), with or without secondary generalization, for ≥2 years. Have residual POS despite having been treated in the past with at least 2 approved anti-epilepsy drugs (AEDs) either alone or in combination * Based on history, participants would be anticipated to have at least 3 POS during each 4-week Baseline period and unlikely to have 21 or more consecutive POS-free days * Currently being treated and maintained with a stable regimen of 1, 2, or 3 AEDs * Able and willing to maintain daily seizure calendar * Able and willing to take drug with food twice daily * Sexually active women of childbearing potential must use acceptable birth control and have a negative pregnancy test at all visits Exclusion Criteria: * Have had previous exposure to ganaxolone * Known sensitivity or allergy to any component in the study drug, progesterone, or other related steroid compounds * Exposure to any investigational drug or device \<30 days prior to screening, or plans to take another investigational drug at any time during the study * Time of onset of epilepsy treatment \<2 years prior to enrollment * Have generalized …