The FDA recently approved a new oral suspension therapy, Ztalmy (ganaxolone) to treat seizures associated with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) in patients 2 years of age and older. This is the first treatment for seizures associated with CDD and the first treatment specifically for CDD. Ztalmy was developed by Marinus Pharmaceuticals and is supplied as an oral suspension.
Patients with CDKL5 deficiency disorder (CDD) typically have infantile-onset epilepsy that responds poorly to previously available treatments. Symptoms include hypotonia (poor muscle tone), severe developmental and cognitive delays with little or no speech production, fine and gross motor impairment (including inability to walk for most patients), cortical visual impairment, behavioral abnormalities, and sleep and digestive difficulties.
CDD is a rare disease with an incidence of between 1 in 40,000-60,000 live births, making it one of the most common genetic forms of epilepsy. This translates into ~6,500 lives in the US.
Marinus announced that Ztalmy will launch in Q3 pending DEA controlled substance approval. It will have a WAC of $133,000 per patient per year and will average $105,000 per patient per year after discounts.
Given the small patient opportunity and clinical complexity of the therapy it is very likely that access to Ztalmy will be limited to a specialty pharmacy.