Marinus Pharmaceuticals, Inc. (Nasdaq: MRNS), a pharmaceutical company dedicated to the development of innovative therapeutics to treat seizure disorders, today announced that the U.S. Food and Drug Administration (FDA) has approved Ztalmy® (ganaxolone) oral suspension for the treatment of seizures associated with cyclin-dependent kinase-like 5 deficiency disorder (CDD), a rare form of genetic epilepsy, in patients two years of age and older.1 Ztalmy, the first FDA approved treatment specifically in CDD, is a neuroactive steroid that acts as a positive allosteric modulator of the GABAA receptor. It is expected to be available through a designated specialty pharmacy in July 2022.
“Today is a historic milestone not only for Marinus but for CDD patients, families and caregivers who have long been navigating the unpredictable, often devastating reality of living with uncontrolled seizures,” said Scott Braunstein, M.D., Chief Executive Officer of Marinus. “The approval of Ztalmy would not have been possible without the patients, caregivers and investigators who participated in the clinical trials to develop this important new therapy. We are grateful and humbled by the opportunity to bring the first and only FDA-approved treatment for seizures associated with CDD to this community.
CDD is a serious and rare genetic disorder characterized by early‑onset, difficult‑to‑control seizures and severe neuro‑developmental impairment.2 It’s caused by a mutation of the cyclin-dependent kinase-like 5 (CDKL5) gene, located on the X chromosome. The CDKL5 gene produces a protein that is important for normal brain development and function. 3
“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,” said Scott Demarest, M.D., Principal Investigator (PI) for the Marigold trial and neurologist and Clinical Director of Precision Medicine at Children’s Hospital Colorado. “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.” Dr. Demarest is also PI of the International CDKL5 Clinical Research Network and Assistant Professor of Pediatrics-Neurology at the University of Colorado School of Medicine.
The approval of Ztalmy in CDD is based on data from the Phase 3 Marigold double-blind placebo-controlled trial, in which 101 patients were randomized and individuals treated with Ztalmy showed a median 30.7% reduction in 28-day major motor seizure frequency, compared to a median 6.9% reduction for those receiving placebo, achieving the trial’s primary endpoint (p=0.0036). In the Marigold open label extension study, patients treated with Ztalmy for at least 12 months (n=48) experienced a median 49.6% reduction in major motor seizure frequency. In the clinical development program, Ztalmy demonstrated efficacy, safety and tolerability with the most common adverse reactions (incidence >/5% and at least twice the rate of placebo) in the Ztalmy group being somnolence, pyrexia, salivary hypersecretion and seasonal allergy.
“As the mother of a daughter living with CDD, I’ve experienced first-hand the devastating impact seizures can have on these patients,” said Karen Utley, President and Co-founder of the International Foundation for CDKL5 Research. “This approval is monumental for the CDD community—bringing not only the first approved treatment option specifically for CDD patients, but renewed hope to those who have struggled to find medications that are effective in significantly reducing the number of seizures these patients experience on a daily basis.
Ztalmy is expected to be commercially available in the U.S. in July following scheduling by the U.S. Drug Enforcement Administration. To support the CDD community, Marinus plans to launch The Ztalmy One™ Program, a comprehensive patient services program to provide assistance with product access, ongoing support to patients, caregivers and their medical teams, and financial support to eligible patients.
The FDA reviewed Ztalmy under Priority Review and granted Ztalmy orphan drug and Rare Pediatric Disease designations for the treatment of CDD. With the approval, the FDA awarded a Rare Pediatric Disease Priority Review Voucher (PRV), which Marinus plans to monetize.
