Praxis has also announced a “successful” pre-NDA meeting with the FDA for its essential tremor drug candidate ulixacaltamide, for which an approval application is slated for early 2026.
Praxis Precision Medicines has ended a mid-stage epilepsy study for its investigational sodium current blocker relutrigine ahead of schedule because of its strong performance.
Details were scant in the news release on Thursday, with the Boston biotech revealing only that a data monitoring board recommended to “stop the study early for efficacy.” Praxis is testing relutrigine in the Phase II EMBOLD trial of patients with developmental and epileptic encephalopathies (DEE) linked to SCN8A and SCN2A mutations.
The study’s primary completion date is March 23, 2026. Praxis will present detailed findings on Dec. 6 at the American Epilepsy Society conference. With EMBOLD’s success, Praxis will also meet with the FDA in the coming weeks to discuss its findings and identify the next steps forward for relutrigine.
Truist Securities were bullish about the outcome of EMBOLD, writing in a Thursday note that relutrigine could hit peak U.S. sales of approximately $650 million by 2037. This forecast could still be “conservative,” Truist continued, “given likely broader utilization or relutrigine in other types of DEE, once relutrigine is approved for SCN2A/8A.”
Relutrigine is an oral, small molecule drug that works by precisely modulating sodium channels, inhibiting persistent currents across these gates, which according to Praxis is a major driver of symptoms in severe cases of DEE. Previous studies and cohorts have shown that relutrigine is well-tolerated, elicits biomarker changes consistent with sodium channel modulation and leads to “robust” improvements in motor seizures.
Also on Thursday, Praxis announced that it has wrapped up a pre-NDA meeting with the FDA for its calcium channel inhibitor ulixacaltamide for essential tremors (ET). The biotech has also aligned with the agency on what the application should contain and expects to make the submission early next year.
As in the case of the epilepsy announcement, Praxis did not reveal much detail about the ulixacaltamide filing. Still, analysts at Jefferies took the positive FDA meeting as a good signal. “We remain 70%+ confident in approval,” they wrote to investors on Thursday, noting that the drug could hit “$2.5B+ peak sales,” though this forecast could still be “conservative.”
Truist was similarly positive and had a higher peak estimate for ulixacaltamide, which the firm said could reach “>$3BN” in the U.S. by around 2040. Thursday’s back-to-back updates from Praxis, Truist added, “further de-risks both ET and DEE programs.”
