Praxis Reports 77% Seizure Reduction in SCN2A-DEE Trial with Elsunersen
Elsunersen produced a 77% placebo-adjusted seizure reduction (p=0.015) in nine pediatric SCN2A-DEE patients over 24 weeks, with 71% achieving over 50% seizure reduction by period six and sustained benefit in a one-year extension. All treated patients improved sleep, motor function, muscle tone and attention with no drug-related serious adverse events.
1. EMBRAVE Part A Trial Design
The EMBRAVE Part A study is a randomized, placebo-controlled Phase 1/2 trial in nine children aged 2–12 with SCN2A early-onset developmental and epileptic encephalopathy. Patients were randomized 3:1 to receive monthly ascending doses of elsunersen over 24 weeks, followed by an open-label extension for responders.
2. Efficacy Outcomes
Treatment with elsunersen achieved a 77% placebo-adjusted reduction in monthly seizures (p=0.015, 95% CI 33–92). Seventy-one percent of treated patients saw over a 50% drop in seizures by period six, 57% experienced at least 28 days without seizures, and benefits persisted through one year of open-label dosing.
3. Safety Profile
Elsunersen was well tolerated with no treatment-related serious adverse events or neuroinflammation signals and no discontinuations. Most adverse events were mild to moderate, consistent with earlier trial phases and unrelated to the study drug.
4. Next Development Steps
Praxis is advancing its pivotal EMBRAVE3 study to confirm these findings in a larger, placebo-controlled setting. Additional data readouts and regulatory interactions are planned to support potential registration of elsunersen for SCN2A-DEE.