Praxis Reassesses Vormatrigine Program After Pivotal Epilepsy Study Misses Primary Endpoint

Praxis Precision Medicines Inc. (NASDAQ:PRAX) on Monday reported results from its Phase 2/3 POWER1 study of vormatrigine for focal onset seizures.

The company said the overall outcome fell short of expectations but highlighted encouraging findings from the higher-dose treatment arm.

Higher-Dose Arm Shows Encouraging Signal Despite Trial Outcome

The study in highly refractory patients with focal onset seizures did not meet its primary success measure of change in monthly seizure frequency.

Focal onset seizures (formerly called a partial seizure) begin in a specific, localized area on one side of the brain.

Secondary measure, the 50% response rate, was met, and seizure reduction during the second half of the study on the higher dose (30 mg) was more pronounced.

"While the results for POWER1 were not what we hoped for, we are encouraged by the signal we saw on the higher dose arm, the low discontinuation rate, and solid safety profile," Souza said.

Open-Label Extension Enrollment Remains Strong

The company on Monday said that 90% of patients from the vormatrigine arm transitioned to and remain in the open-label extension (OLE) study.

Praxis is pausing enrollment in the POWER2 study to reassess the vormatrigine program and determine potential modifications.

The genetic epilepsies company also remains focused on preparations for the planned launches of relutrigine and ulixacaltamide.

Prior Data

According to the company, preclinical research suggests vormatrigine may offer differentiation from current standard-of-care therapies.

Laboratory studies showed selectivity for disease-state sodium channel hyperexcitability, while animal studies demonstrated strong activity in the maximal electroshock seizure model, which is commonly used to predict efficacy in focal epilepsy.

Praxis also noted that data from the RADIANT study previously showed seizure reduction and a generally safe and well-tolerated profile for the investigational therapy.

In April, Praxis Precision released results from the EMBRAVE Part A Trial of Elsunersen for SCN2A early-onset development and epileptic encephalopathy.

Praxis said elsunersen demonstrated a placebo-adjusted seizure reduction from baseline of 77% (p=0.015) in pediatric patients with SCN2A developmental and epileptic encephalopathy.

PRAX Stock Price Activity: Praxis Precision Medicine shares were down 9.30% at $304.00 during premarket trading on Tuesday, according to Benzinga Pro.

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