Marinus Pharmaceuticals has received the US Food and Drug Administration (FDA) approval for Ztalmy (ganaxolone) oral suspension to treat a rare type of genetic epilepsy related to seizures.
Ztalmy is a neuroactive steroid, indicated for seizures associated with cyclin-dependent kinase-like 5 deficiency disorder (CDD) in patients, aged two years and above.
CDD is a serious and rare genetic disorder caused by a mutation of the cyclin-dependent kinase-like 5 (CDKL5) gene located on the X chromosome.
The drug acts as a positive allosteric modulator of the GABAA receptor and is the first FDA approved treatment specifically in CDD, said the company.
Marinus is expected to commercialise the drug through a designated speciality pharmacy in July 2022, following scheduling by the US Drug Enforcement Administration.
Marinus CEO Scott Braunstein said: “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.
“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.”
The FDA approval was based on data from the Phase 3 Marigold trial which evaluated Ztalmy, compared to placebo in 101 patients.
The US health agency reviewed the drug under Priority Review and granted an orphan drug and Rare Paediatric Disease designations for the treatment of CDD.
In the study, Ztalmy has showed a median reduction of 30.7% major motor seizure frequency, compared to a 6.9% reduction for placebo, which is the primary endpoint.
In the open-label extension study, patients receiving Ztalmy for at least 12 months experienced a median reduction in major motor seizure frequency of 49.6%.
The drug showed efficacy, safety and tolerability with the most common adverse reactions including somnolence, pyrexia, salivary hypersecretion and seasonal allergy, in the study.
Furthermore, Marinus intends to launch ‘The ZTALMY One Programme’, to help with product access, support patients, caregivers and medical teams, and funding for eligible patients.
Marigold trial principal investigator Scott Demarest said: “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.
“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.”