The FDA granted Breakthrough Therapy Designation to elsunersen for seizures in SCN2A developmental and epileptic encephalopathy. The decision follows data showing a 77% sham-adjusted reduction in monthly seizures. Shares rose 4% on the news.
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Praxis Precision Medicines gains 4% on FDA breakthrough therapy for elsunersen
Praxis Precision Medicines Inc. gained 4% after the US Food and Drug Administration granted Breakthrough Therapy Designation to elsunersen for seizures associated with SCN2A developmental and epileptic encephalopathy.
"This designation reflects the FDA's recognition of both the urgency of the unmet need in SCN2A-DEE and the strength of our clinical data," Marcio Souza, president and chief executive officer of Praxis, said.
The designation was supported by data from the EMBRAVE Part A trial, a randomized, sham-controlled Phase 1/2 study in nine pediatric patients aged 2 to 12 years. Elsunersen treatment led to a 77% sham-adjusted reduction in monthly seizures from baseline (p=0.015), with 71% of patients achieving a greater than 50% reduction and 57% experiencing at least one 28-day seizure-free period during the six-month treatment phase. Efficacy was sustained in the open-label extension for up to one year. All treated patients, and none on sham, showed improvements across sleep, motor function, muscle tone, attention or neuropsychomotor development. The therapy was well-tolerated with no drug-related serious adverse events and no discontinuations.
Elsunersen, an antisense oligonucleotide designed to reduce SCN2A gene expression, now holds Breakthrough Therapy, Orphan Drug and Rare Pediatric Disease designations from the FDA, plus Orphan Drug and PRIME status from the European Medicines Agency. The pivotal EMBRAVE3 study is enrolling about 30 patients under a streamlined single-arm registrational pathway aligned with the FDA.
The therapy targets early-seizure-onset SCN2A-DEE, a rare genetic epilepsy caused by gain-of-function mutations in the SCN2A gene. Seizures typically begin in infancy and are associated with developmental impairment. No approved therapies currently address the underlying genetic cause. The program is being developed in collaboration with Ionis Pharmaceuticals Inc. and RogCon Inc.
The breakthrough designation could shorten the development and review timeline for elsunersen, potentially making it the first disease-modifying therapy for SCN2A gain-of-function epilepsy. Investors will watch enrollment progress in the EMBRAVE3 registrational trial for the next catalyst.
This article is for informational purposes only and does not constitute investment advice.
[1] Praxis' Seizure Drug Move Towards Faster Development After Positive Trial Results[2] Praxis Precision Medicines Gains After FDA Grants Breakthrough Therapy Designation[3] Praxis Precision Medicines Receives FDA Breakthrough Therapy Designation for Elsunersen for the Treatment of Seizures Associated with SCN2A Developmental and Epileptic ...[4] Praxis Shares Rise on FDA Breakthrough Therapy Designation for Elsunersen
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