The U.S. Food and Drug Administration (FDA) has approved ganaxolone for the treatment of seizures associated with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder, a rare form of genetic epilepsy, in patients two years of age and older.

Ganaxolone is a neuroactive steroid that acts as a positive allosteric modulator of the GABAA receptor.

CDKL5) deficiency disorder is a rare genetic disorder characterized by difficult‑to‑control seizures and severe neuro‑developmental impairment. It’s caused by a mutation of the cyclin-dependent kinase-like 5 (CDKL5) gene, located on the X chromosome.

The FDA approval was partially based on data from a double-blind placebo-controlled, phase 3 trial, in which 101 patients were randomized to receive ganaxolone or placebo.  The ganaxolone-treated group showed a median 30.7% reduction in 28-day major motor seizure frequency, compared to a median 6.9% reduction in the placebo group (P = .0036). In the open label extension study, patients treated with ganaxolone for at least 12 months experienced a median 49.6% reduction in major motor seizure frequency. The most common adverse reactions in the ganaxolone-treated group were somnolence, pyrexia, salivary hypersecretion and seasonal allergy.

In a news release, Scott Demarest, MD, Principal Investigator (PI) for the Marigold trial and Clinical Director of Precision Medicine at Children’s Hospital Colorado stated “There has been a great unmet medical need for treatments that address seizures associated with CDKL5 deficiency disorder given their prominent role and profound impact on patients,” adding, “To date, antiseizure treatment decisions have been based on very limited clinical evidence in this patient population and the resulting outcomes underscore the need for therapies that further improve seizure control. Thanks to our research and this trial, we now have the first treatment specifically approved for seizures associated with CDKL5 deficiency disorder that was shown to have a positive benefit-risk profile.”

Ganaxolone, under the tradename Ztalmy, is expected to be commercially available in the U.S. in July, according to the manufacturers of the orphan drug, Marinus Pharmaceuticals.

The FDA approval also comes with a Rare Pediatric Disease Priority Review Voucher (PRV), which Marinus plans to sell to another company. Recently,

To learn more about this and other neurological disorders, visit checkrare.com/diseases/neurology-nervous-system-diseases/