A Randomized, Double-blind, Placebo-Controlled Phase 3 Study Evaluating XEN1101 as Adjunctive Therapy in Focal-Onset Seizures

What this Trial Is About

Researchers are evaluating the clinical efficacy, safety, and tolerability of XEN1101 as an additional treatment for people with focal-onset seizures in a Phase 3 randomized, double-blind, placebo-controlled study. This trial aims to compare two doses of XEN1101 with a placebo to see how well the medication can reduce seizure frequency in patients who continue their current antiseizure medications. The study involves adults diagnosed with focal epilepsy who have tried at least two antiseizure medicines without achieving seizure freedom. About 360 participants will be randomly assigned to receive either 25 mg or 15 mg of XEN1101 or a placebo once daily with an evening meal. The study includes up to 9.5 weeks of baseline monitoring to track seizure frequency followed by 12 weeks of blinded treatment. Participants maintaining the study drug can then join an open-label extension to continue treatment or enter an 8-week follow-up after treatment ends. Throughout the study, participants will keep accurate seizure diaries and continue their stable antiseizure medications. Researchers will measure the median percentage change in seizure frequency from baseline through the 12-week treatment period, along with secondary outcomes like the proportion of participants with at least a 50 reduction in seizures and patient-reported improvement. Safety will be monitored from screening until 56 days after the last dose. Overall, participants are involved for the baseline, treatment, and follow-up phases lasting several months.

A Randomized Study of XEN1101 Versus Placebo in Focal-Onset Seizures (X-TOLE3)