The two phase III trials will evaluate the safety and efficacy of retigabine, a first-in-class neuronal potassium channel opener, in patients with refractory partial-onset seizures who are receiving one, two or three concomitant antiepileptic drugs (AEDs). The second pivotal trial in the program is expected to achieve full enrollment in the fall of this year.
In all, 306 patients have been enrolled into the study which is being conducted at 49 sites across the US, Argentina, Mexico, Brazil and Canada. The second study, which is targeted to enroll 510 patients, is being conducted in 72 sites across Europe, Israel, Australia, South Africa and the US.
Both studies are randomized, double-blind, placebo-controlled, multicenter, parallel group studies. The primary endpoint of the first study is a change in total partial seizure frequency per four weeks from baseline to the double-blind period (titration phase and maintenance phase).
For European Medicines Agency review, the primary endpoint is the proportion of responders, where a “responder” is defined as a patient experiencing a reduction of at least 50% in total partial seizure frequency per four weeks from baseline to double-blind period.
Epilepsy is one of the most common neurological diseases, affecting approximately 50 million people worldwide. It is a brain disorder in which clusters of nerve cells, or neurons, in the brain sometimes signal abnormally, causing a seizure. Seizures can cause changes in behavior and emotions, strange sensations and sometimes convulsions, muscle spasms and loss of consciousness.