Investigation of the efficacy and adverse effects of lacosamide over 36 months.

OBJECTIVE: To evaluate the efficacy and retention rate of lacosamide (LCM) over 36 months as a treatment for children and adolescents with focal and generalized epilepsy based on a retrospective study. METHODS: All patients prescribed LCM as monotherapy and add-on therapy between October 2016 and September 2019 at Jichi Children's Medical Center Tochigi were included in the study. The response rate, retention rate, and adverse effects were calculated. RESULTS: A total of 126 (female, n = 73) patients of 1.3 to 34.9 years old (median age: 12.8 years; mean ± SD 13.2 ± 6.6 years) received LCM as monotherapy or add-on treatment for focal, generalized, and combined focal and generalized epilepsy. The response rate was 40.5% at 3 months, 40.5% at 6 months, 38.1% at 9 months, 35.7% at 12 months, 25.9% at 24 months, and 29.4% at 36 months. For 34 patients who were observable for 36 months, the retention rate was 70.6% at 3 months, but then gradually declined to 34.8% at 36 months. According to the number of concomitant anti-seizure medications (ASMs), the retention rate was higher in patients receiving <3 ASMs than in those receiving ≥3 ASMs at all observation points. The most common adverse effects were somnolence in 21 patients (16.7%) and dizziness in 5 patients (39.7%). CONCLUSION: Our response rate was lower and our retention rate was higher in comparison to a previous study that observed patients over 36 months. Further prospective studies in children are required to confirm the response rate and retention rate in patients treated with LCM over 36 months.