Abstracts

Rationale: In spite of the introduction new AEDs between 1993-2006 there has been no significant reduction in the rate of pharmacoresistant epilepsy. Lacosamide is a new anticonvulsant approved for treatment of refractory localization-related (LRE) epilepsy in 2009. In the present study, we sought to evaluate efficacy of lacosamide as adjunctive treatment refractory LRE in adults at a single epilepsy center. Methods: Patients with refractory LRE with partial complex seizures evaluated and treated between 2010-2011 at a single epilepsy center in whom lacosamide treatment was initiated were followed prospectively in an open label study . Patients were followed prospectively from the time of initiation of lacosamide treatment. Seizure diaries were reviewed at regular intervals by epileptologists in face to face interviews with the patients/caregivers. Lacosamide dosing was titrated up to either seizure freedom or clinical toxicity. Background medications were chosen on clinical grounds and were adjusted according to best clinical judgment of treating physicians. Only patients with lacosamide treatment of ≥ 6 months lacosamide treatment or with lacosamide treatment failure before 6 months of treatment were included in the analysis. Seizure freedom was defined as 0 seizures for ≥ 6 months. Results: 70 patients were treated with lacosamide (30 M, 40 F). Average age was 38.5 years, duration of epilepsy was 20.7 years, average number of previous AEDs 5.9, average number of concomitant AEDs 2.1, and average pre-treatment seizure frequency 24.4 per month. Average treatment duration was 12.85 months. Mean monthly seizure frequency decreased by 37.64 % to 9.2/month (62.3%). 11 patients (15.7%) became seizure free. 19 patients (27.1%) had ≥ 75% seizure frequency reduction. Average final dose was 385 mg (range 200-850 mg). Side effects occurred in 49.2%patients during treatment initiation, and declined to 19.7% patients at final treatment dose, following dose adjustment. 25/50 (35.7%) patients stopped lacosamide, 7 (10%) because of adverse events, 18 (25.7%) because of lack of efficacy. Conclusions: Lacosamide is effective treatment in patients with refractory localization-related epilepsy. Unlike in the fixed setting of the pivotal Phase 2/3 studies, a significant proportion of previously refractory patients may achieve seizure freedom with adjunctive lacosamide treatment in the clinical setting of adjustable dose and concomitant medications.