FDA approves eslicarbazepine for the treatment of epilepsy Eslicarbazepine acetate (Aptiom) has been approved by the FDA for the add-on treatment of partial-onset seizures in epilepsy. The product is a prodrug of S(+)-licarbazepine, the active metabolite of the existing antiepileptic drug oxcarbazepine (Trileptal). Pharmacokinetic trials have demonstrated that eslicarbazepine acetate is metabolized more slowly, reducing peak levels of metabolites in the circulation, and is thought to improve its tolerability in some patients. The FDA said the drug’s approval was based primarily on three clinical studies showing that eslicarbazepine was more effective than placebo in reducing seizure frequency. Results from the three 12-week, double-blind studies showed that 21.5% of the 279 patients assigned to the placebo group had a reduction in seizure frequency of at least 50%. They were classified as responders – compared with 36.5% of 262 patients receiving the active drug 800 mg/day and 43.5% of 253 patients receiving the active drug 1200 mg/day who achieved this result (p less than 0.001 compared with the placebo group). Patients in these studies continued to take the various antiepileptic drugs they were previously using. Common side effects of eslicarbazepine listed by the FDA include dizziness, sleepiness, nausea, headache, diplopia, vomiting, fatigue, and coordination problems. Eslicarbazepine is also in clinical studies that can be used for bipolar disorder.