Long‐term efficacy and safety of eslicarbazepine acetate: Results of a 1‐year open‐label extension study in partial‐onset seizures in adults with epilepsy

Abstract

To evaluate the long-term efficacy and safety of once daily eslicarbazepine acetate (ESL) as adjunctive therapy for partial-onset seizures in adults with epilepsy. One-year open-label treatment extension with ESL in patients who completed a placebo-controlled pivotal study (Epilepsia 2009; 50: 454-463). Starting dose was 800 mg once daily, for 4 weeks; thereafter, dose could be titrated up or down. Doses of concomitant antiepileptic drugs were to be kept stable. Overall, 314 patients were enrolled. The intent-to-treat population consisted of 312 patients, and 239 (76.6%) completed 1 year of treatment. ESL median dose was 800 mg once daily. Compared to baseline, median seizure frequency decreased by 39% during the first 4 weeks and between 48% and 56% thereafter. The responder rate (≥50% seizure reduction) was 41% during weeks 1-4 and, thereafter ranged between 48% and 53%. The proportion of seizure-free patients per 12-week interval ranged between 8.7% and 12.5%. Quality of life, as measured by the Quality of Life in Epilepsy Inventory-31 (QOLIE-31), and depressive symptoms, as measured by the Montgomery Asberg Depression Rating Scale (MADRS), improved significantly compared to baseline. Treatment-emergent adverse events (TEAEs) were reported by 51% of patients. The most frequent TEAEs were headache (10%), dizziness (10%), diplopia (5%), and nasopharyngitis (5%). TEAEs were mostly (97%) of mild to moderate intensity. Eleven patients (3.5%) discontinued due to TEAEs. There were no results of laboratory tests raising safety concerns. Sustained therapeutic effect, favorable tolerability and safety, and an improvement in quality of life and depressive symptoms were observed during long-term add-on treatment of partial-onset seizures in adults with once daily ESL.