Drug, now in testing, has promise for epileptic seizures

By Paul Sisson, The San Diego Union-Tribune

SAN DIEGO — More than 100 locations nationwide participating in new clinical trials for a drug that shows promise for treating epileptic seizures among patients for whom other medications do not work.

The drug, BHV-7000, activates potassium receptors in the brain in a way that appears to modulate seizures, explained Dr. Taha Gholipour, a neurologist at the University of California, San Diego, a participant in the trial and the study’s local investigator. Other commonly prescribed anti-seizure medications act on sodium and calcium channels in neurons, routes that are effective for some but not all patients.

About 40% of the estimated 1.5 million people with epilepsy are resistant to drugs that engage the calcium and sodium routes, meaning that having a third avenue, through potassium, would be a major expansion of the options for treating seizures.

“The potassium channel is not completely new or unknown in our neuroscience community — there have been many attempts in the past to study this route — but we have had no success in getting a drug that has minimal side effects and also effective seizure control,” Gholipour said. “But years of preclinical work in labs, in cell models, in animal models, and then in early clinical trials in humans, have shown that it looks like this drug is well tolerated and potent in controlling seizures, which is exciting news.”

A phase 1 trial tested the drug in 58 patients, mostly white men with a median age of 40, finding that the main side effects, observed in just a handful of participants, were headaches and abdominal discomfort, which resolved when they stoped taking the drug.

Biohaven Ltd. a Connecticut-based biopharmaceutical company, is working to enroll 390 participants for the second and third phases of a clinical trial designed to determine whether the drug can decrease the average seizure frequency in patients diagnosed with focal onset epilepsy, which causes seizures in a specific part of the brain.

Participants must be aged 18 to 75 and are randomly assigned to receive one of two different dose strengths or a placebo, a non-active dose that is vital for comparison purposes. A diagnosis of focal onset epilepsy must have been made at least one year prior and participants must experience four or more seizures in a 28-day period, have been unsuccessfully treated with at least two anti-seizure medications, and must be “on a stable dose of at least one and up to three anti-seizure treatments.”