Praxis Precision Medicines, a clinical-stage biopharmaceutical company, has announced a major breakthrough in its rare paediatric epilepsy study.

The EMBOLD study evaluated relutrigine for patients with SCN2A and SCN8A developmental and epileptic encephalopathies (DEEs). The Data Monitoring Committee recommended stopping the study early for efficacy, signalling the therapy’s promising impact.

“SCN2A and SCN8A DEEs are devastating conditions with extremely high mortality due to the debilitating seizure burden they impose on patients, and there are currently no approved treatment options. Our progress represents an important milestone towards delivering the first therapy ever designed for these children and their families,” said Marcio Souza, president and CEO. “We look forward to sharing the results at the American Epilepsy Society Annual Meeting.”

The FDA has confirmed a meeting to review the data and discuss next steps in the coming weeks. Praxis will decide on the timing of a New Drug Application (NDA) filing for relutrigine after the meeting.

Relutrigine is a first-in-class small molecule in development for DEEs, acting as a preferential inhibitor of persistent sodium current, a key driver of seizures in severe DEEs. Its precision sodium channel (NaV) modulation shows superior selectivity for disease-state NaV hyperexcitability.

In preclinical studies, relutrigine achieved dose-dependent seizure inhibition and, in some cases, complete seizure control in SCN2A, SCN8A, and other DEE mouse models. Phase 1 studies show it is generally well-tolerated, and Phase 2 EMBOLD cohort 1 data demonstrated robust, short- and long-term motor seizure improvements, including maintained seizure freedom in some patients.

Relutrigine has received Orphan Drug Designation and Rare Pediatric Disease Designation from the FDA for SCN2A-DEE, SCN8A-DEE, and Dravet syndrome, as well as Breakthrough Therapy Designation and similar European Medicines Agency designations.