The NDA covers three indications: as an add-on therapy for treatment of partial-onset seizures, including those associated with Lennox-Gastaut syndrome (LGS) in patients 2 and older; as a single therapy for partial-onset or primary general tonic-clonic seizures in patients 2 and older; and as preventative migraine treatment in patients 12 and older.
“Topiramate is one of the most widely compounded oral liquids, and our product addresses the unmet need for pediatric-friendly formulations of the molecule. We look forward to working with the FDA to bring a safe, effective, FDA-approved product to patients and caregivers as quickly as possible,” Sean Brynjelsen, Eton’s CEO, said in a press release.
FDA approval would make topiramate oral solution the first approved liquid formulation of the medicine. Topiramate, an anticonvulsant that is used to treat seizures in adults and children and to prevent migraines in adults and adolescents, is currently available only as tablets and capsules.
The company expects the liquid formulation to enable more precise dosing than the solid forms allow. It also addresses challenges related to dysphagia (difficulty swallowing), which often makes taking solid medication difficult for patients.
A bioequivalence study in healthy male volunteers had shown topiramate oral solution to be equivalent (functionally identical) to solid forms of of the medicine, when taken under fasting conditions. A food effect study further indicated that food did not diminish liquid topiramate’s effect or its bioavailability (the extent to which a medicine reaches its intended destination in the body).
ET-101 is Eton’s third neurology-focused liquid product candidate to be submitted to the FDA. The other two also address seizures: zonisamide oral suspension (ET-104), for those associated with epilepsy; and lamotrigine oral suspension (ET-105), for partial seizures, primary generalized tonic-clonic seizures, and generalized seizures of LGS in patients 2 and older.
Eton anticipates the approval and launch of all three of neurology product candidates in 2021.
Lennox-Gastaut syndrome is a severe form of epilepsy with few effective treatment options. It often features co-occurring conditions, including learning disabilities, mobility problems, and developmental delays.