On Dec. 2, an international team of researchers will present positive results from their study, which analyzed the safety and efficacy of a new drug for focal seizures. The drug, padsevonil, has previously demonstrated full seizure protection in animal models (abstract 1.283). The study will be presented at the 2017 American Epilepsy Society (AES) annual meeting in Washington, DC.

Epilepsy. (Source: Pixabay)

The phase II trial enrolled 55 patients who had uncontrolled, observable focal seizures at least four times a week after failing four or more antiepileptic drugs. All patients continued on a regimen of at least one antiepileptic drug. The researchers randomized participants on a 1:1 basis to receive either padsevonil or placebo over a three-week double-blind inpatient period that included two weeks of maintenance and one week of up-titration followed by an eight-week open-label outpatient period.

The participants had a baseline median seizure frequency of 8.24. During the two-week inpatient maintenance period, participants in the padsevonil group experienced more than four times the reduction in seizures than those in the placebo arm, 53.7% compared to 12.5%. The padsevonil group also had nearly three times the rate of 75% responders, 30.8% vs 11.1%, and twice as many participants who were seizure free (two versus one).

During the outpatient period, 31.4% of participants were 75% responders and participants had a median reduction in weekly focal seizures of 55.2%. No patients were seizure free, according to the study. 

Treatment emergent adverse effects (TEAEs) were experienced by 90.9% of participants with padsevonil, with more than 25% reporting somnolence, dizziness or headache. Of the two participants who experienced serious TEAEs, one patient had status epilepticus and one had impaired judgment/delirium/dysphoria. In addition, 18 patients required dosage changes as a result of side effects.