Ganaxolone: A Review in Epileptic Seizures Associated with Cyclin-Dependent Kinase-Like 5 Deficiency Disorder

Oral ganaxolone (ZTALMY^®), a synthetic analogue of the endogenous neuroactive steroid allopregnanolone, acts as a positive allosteric modulator of synaptic and extra-synaptic γ-aminobutyric acid (GABA) type A receptor function in the CNS. In the EU and the UK, it is approved for the adjunctive treatment of epileptic seizures associated with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) in patients aged 2-17 years. In a multinational phase III study (Marigold), 17 weeks' therapy with adjunctive ganaxolone, administered orally three times daily with food, significantly reduced 28-day major motor seizure frequency from baseline versus placebo in patients aged 2-19 years with CDD-associated refractory epilepsy. Antiepileptic efficacy was generally sustained through 2 years of treatment. Ganaxolone was generally well tolerated in Marigold. While somnolence and sedation are related to the dose of ganaxolone, they appear early in treatment and may decrease with continued therapy. Thus, although current evidence is somewhat limited, adjunctive ganaxolone could be a valuable therapeutic option for patients aged 2-17 years with epileptic seizures associated with CDD.