Abstracts

Rationale: Lacosamide (LAC) is an FDA-approved antiepileptic drug (AED) for use as adjunctive therapy in patients 17 years or older with partial-onset epilepsy (PE). Several case series have demonstrated efficacy of LAC in adults with refractory generalized epilepsy (GE). A few case series and prospective trials have suggested that LAC is safe and effective in children with PE. There is very little data on the use of LAC in children with GE. The objective of this study was to evaluate the efficacy and tolerability of LAC in pediatric patients with refractory GE. Methods: We retrospectively reviewed the records of children with refractory GE treated with LAC in our institution from 2009 to 2013. Twenty-one patients were divided into 2 subgroups: I) Lennox Gastaut Syndrome (LGS) (n=8, 38.1%) and II) Other generalized epilepsies (n=13, 61.9%) which included 8 patients with primary GE, 1 with Doose Syndrome, and 4 with other GEs (genetic or idiopathic). Data collected were age, gender, developmental delay/cognitive deficit, epilepsy type, prior AEDs, LAC dosage, follow-up duration, treatment response, and adverse effects. Efficacy was defined as seizure freedom or >50% seizure reduction. Descriptive analysis of data was performed in all patients and in each subgroup. Seizure freedom was compared between both subgroups using χ² analysis. Results: Eleven patients were female (52.4%) and 10 were male (47.6%). Mean age at treatment onset was 11.9 years (range 4.1-19.5). Developmental delay/cognitive deficit was present in 10 patients (47.6%). Overall, 20 patients (95%) had failed 2 or more AEDs. LAC was used as monotherapy (n=4, 19%) or adjunct therapy (n=17, 81%). LAC mean maintenance dose was 6.87 mg/kg/day (range: 1.7-14.3). Mean follow-up was 19 months (range 2.7-43.2). In total, 5 patients (23.8%) became seizure free, 9 (43%) had >50% seizure reduction, and 7 (33.3%) were non-responders. In Group I, zero patients were seizure free, but 7 (87.5%) had >50 improvement and 1 (12.5%) did not respond. In Group II, a total of 5 patients (38.5%) became seizure free (p<0.05 vs. Group I), 2 (15.4%) had >50 improvement, and 5 (38.5%) had no change. LAC was discontinued in 7 patients (33.3%) due to lack of efficacy and in 1 (4.8%) due to adverse effects. These were reported in 6 patients (28.6%), including somnolence in 2 and weight loss, tremor, memory problems, or nausea/dizziness in 1 patient each. Conclusions: In this small series of children with refractory GE, LAC was well tolerated and reduced seizure frequency by >50% in 67% of patients. Efficacy was strikingly high in LGS. Seizure freedom was attained in almost 40% of children with other GE. In our experience, LAC is an effective AED in the treatment of children with GE. A larger randomized, prospective study is necessary to confirm our findings.