CDKL5 deficiency disorder causes severe, early-onset, treatment-resistant seizures, and management relied entirely on off-label antiseizure medicines. Ztalmy (ganaxolone) was the first therapy approved for it.
Ganaxolone is a neuroactive steroid that positively modulates both synaptic and extrasynaptic GABA-A receptors, strengthening inhibitory signaling more broadly than conventional benzodiazepines. The oral suspension treats seizures associated with cyclin-dependent kinase-like 5 deficiency disorder in patients 2 years and older.
Ztalmy is a Schedule V controlled substance holding orphan designation, with no approved competitor in the indication. Its extrasynaptic activity and expansion into other rare epilepsies are the key development questions, and it remains the reference asset for CDKL5 trial design.
