FDA has Accepted Application for Rare Epilepsy

The FDA accepted for filing Marinus Pharmaceuticals’ new drug application (NDA) for the use of ganaxolone in the treatment of seizures associated with CDKL5 deficiency disorder, a rare, genetic epilepsy. The NDA was granted Priority Review designation and the FDA assigned a Prescription Drug User Fee Act (PDUFA) action date of March 20, 2022.

The application is supported by data from the Marigold study, a phase 3 trial in 101 patients. Patients treated with ganaxolone showed a 30.7% median reduction in 28-day major motor seizure frequency, compared with a 6.9% reduction for those receiving placebo. Patients in the open-label extension study treated with ganaxolone for at least 12 months experienced a median 49.6% reduction in major motor seizure frequency.

Ganaxolone received orphan drug designation in June 2017 and a Rare Pediatric Disease designation for CDKL5 deficiency disorder in July 2020.

“The FDA’s acceptance of our NDA submission is an important step toward potentially bringing the first approved therapy specifically for treatment of seizures associated with CDD—a devastating disorder with high unmet medical need—to families and healthcare providers,” Scott Braunstein, M.D., chief executive officer of Marinus Pharmaceuticals, said in a statement. “We believe that ganaxolone has the potential to provide meaningful clinical benefit for patients and we look forward to working closely with the FDA during the review process.”

CDKL5 deficiency is a rare genetic disorder that is caused by a mutation of the cyclin‑dependent kinase‑like 5 (CDKL5) gene, located on the X chromosome. CDKL5 deficiency disorder is characterized by early‑onset, difficult‑to‑control seizures and severe neuro‑developmental impairment. Currently, there are no therapies approved specifically for CDD. The incidence 1 in 40,000 to 60,000 newborns. About 90% of those diagnosed with CDKL5 deficiency disorder are girls.