Open-label, Single-arm Trial of Ganaxolone in CDD Patients 6 Months to Less Than 2 Years Old

This is an open-label, single-arm, 52-week, multicenter trial of adjunctive ganaxolone treatment in participants 6 months to less than 2 years of age with genetically confirmed CDD. The trial consists of an up to 2-week Screening Period, 4-week prospective Baseline Period, followed by 2 parts: Part A; a 17-week ganaxolone treatment phase (including 4 to 5 weeks of ganaxolone titration followed by 12 to 13 weeks of dose maintenance) and Part B; a 35-week ganaxolone maintenance phase, and a 2-week taper period at the end of the trial. Tapering will not apply for participants continuing ganaxolone treatment after the trial. The Screening Period will follow the Screening Visit to ensure caregivers can classify seizures and comply with completion instructions of an electronic seizure and medication diary. This will be followed by a 4-week prospective Baseline Period to assess seizure frequency for trial eligibility. Up to 15 participants will be enrolled to ensure at least 12 participants are evaluable for the primary PK endpoints at the end of Part A of the trial, including at least 3 participants experiencing uncontrolled seizures despite treatment with at least 2 anti-seizure medications. Participants will be monitored at Baseline and at specified visits to assess the exposure, safety and tolerability and activity of ganaxolone. PK samples will be collected at specified timepoints up until completion of Part A. Clinical laboratory testing will be performed at local laboratories at participating sites.