Praxis Precision Medicines Receives FDA Breakthrough Therapy Designation for Relutrigine for the Treatment of Seizures Associated with SCN2A and SCN8A Developmental and Epileptic Encephalopathies

Core Insights - The U.S. FDA has granted Breakthrough Therapy Designation (BTD) for relutrigine, a sodium channel functional state modulator, aimed at treating pediatric patients with SCN2A and SCN8A developmental and epileptic encephalopathies (DEEs) [1][2] - The EMBOLD cohort 2 pivotal trial is expected to deliver topline results in the first half of 2026, with a New Drug Application (NDA) filing to follow [1][3] - Praxis has initiated the EMERALD study to evaluate relutrigine in a broader DEE patient population [1][3] Clinical Trial Results - The EMBOLD cohort 1 study included a severely affected DEE population, with patients averaging three failed treatments prior to enrollment [2] - Results from the open-label extension of the study showed approximately 90% reduction in seizures and an average of 67 days without seizures compared to 3 days in the baseline period [2][4] - During the double-blind period, a placebo-adjusted monthly motor seizure reduction of 46% was observed, with over 30% of patients achieving seizure freedom while on relutrigine [2][4] Drug Mechanism and Designation - Relutrigine is a first-in-class small molecule that preferentially inhibits persistent sodium current, a key driver of seizure symptoms in severe DEEs [4] - The drug has received Orphan Drug Designation (ODD) and Rare Pediatric Disease Designation from the FDA for SCN2A-DEE and SCN8A-DEE, in addition to the BTD [4][5] Company Overview - Praxis Precision Medicines is focused on developing therapies for CNS disorders characterized by neuronal excitation-inhibition imbalance, utilizing genetic insights [6] - The company has a diversified CNS portfolio, including multiple programs across epilepsy and movement disorders, with four clinical-stage product candidates [6]