Long-term use of Levetiracetam in patients with severe childhood-onset epilepsy

Objective: To assess the efficacy and tolerability of Levetiracetam (LEV) in children and adolescents with refractory epilepsy with a special interest in the long-term retention rate. Method: One hundred and twenty-nine patients (83 male, 46 female; mean age 10.6 years/ range: 6 months - 39 years 9 months) were included in a prospective, open-label, add-on trial of LEV for up to 3 years. All patients had severe forms of epilepsy starting before the age of 10 often accompanied by mental retardation. Primary outcome measures were changes in seizure frequency after 6 months on the medication with LEV, with initial responders (> 50% seizure reduction). Further objective was the retention rate of LEV therapy after 3 years defined as percentage of patients still taking LEV. Results: Thirty-five patients (27.1%) were initial responders of which 5 became seizure free. The average maximum LEV dosage was 39.8 mg/kg/day (range: 6-70 mg/kg/day) with no difference responders vs. no responders. The retention rate for responders after 3 years was 22.5%. The rate of side effects was 39.8% in all patients, with the most frequent side effects being fatigue (12.5%), aggressiveness (7.8%) and gastrointestinal disorders (13.3%). Conclusions: Our study in patients with refractory epilepsy suggests that our initial responders were very likely to be still taking LEV after 3 years. We therefore consider treatment with LEV in this special group of patients with refractory epilepsy a promising therapeutic option, because of its favourable tolerance profile, the option of fast titration and the absence of drug interactions. (C) 2007 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.