New Experimental Drug Offers Hope to Epilepsy Patients

In a groundbreaking medical advancement, researchers have unveiled a new experimental drug, XEN1101, that has shown promise in offering relief to those suffering from tough-to-treat epilepsy. This revolutionary drug has reduced or even completely eradicated seizures in some patients with focal epilepsy, who previously did not find relief from an average of six other medications.

Dr. Jacqueline French, the lead researcher and a distinguished professor of neurology at NYU Langone Health in New York City, expressed optimism about the drug’s potential impact. “With this new drug, we anticipate a significant decline in the number of epilepsy patients who grapple with uncontrolled seizures.” she stated.

Highlighting the uniqueness of focal epilepsy, Dr. French shared that it accounts for the majority of epilepsy cases. In this type, seizures originate from a specific area in the brain. “Two-thirds of people with epilepsy suffer from focal epilepsy. The seizures can begin in varied regions, such as the temporal or frontal lobe,” she elaborated.

XEN1101 has a distinct mechanism of action compared to most conventional epilepsy treatments. While standard drugs, termed sodium channel blockers, prevent sodium from entering a cell and thus reduce the cell’s excitability, XEN1101 operates as a potassium channel opener. This means it allows potassium to exit the cell, preventing it from firing and causing a seizure.

However, as with all medications, XEN1101 is not without side effects. Some patients may experience drowsiness or feel unsteady. Dr. French reassured that these effects are dose-dependent and can be effectively managed.

One of the standout features of XEN1101 is its prolonged duration in the body. This longevity means patients won’t need to take it as frequently as other anti-seizure medications. Plus, unlike several current drugs which can take up to 10 weeks to fully work, XEN1101 begins to show its effects almost immediately.

The study, backed by Xenon Pharmaceuticals Inc., involved 285 participants who had been diagnosed with focal seizures. Remarkably, patients who were administered XEN1101 witnessed a significant 33% to 53% reduction in monthly seizures over the trial’s eight-week duration. Comparatively, those on a placebo observed a mere 18% decrease.

The encouraging results prompted many participants to continue with the drug post-trial. Approximately 18% remained seizure-free for six months, and about 11% reported no seizures after a year or longer.

With further trials in the pipeline, there is mounting hope that XEN1101 will soon be accessible to patients. Dr. French concluded, “The unpredictable nature of seizures can be severely debilitating, affecting personal relationships, job prospects, and overall safety. We urgently need to address this. Patients should indeed be hopeful.”


French JA, Porter RJ, Perucca E, et al. Efficacy and Safety of XEN1101, a Novel Potassium Channel Opener, in Adults With Focal Epilepsy: A Phase 2b Randomized Clinical Trial. JAMA Neurol. Published online October 09, 2023. doi:10.1001/jamaneurol.2023.3542