Clinical efficacy and safety of perampanel monotherapy as primary anti-seizure medication in the treatment of pediatric epilepsy: A single-center, prospective, observational study

Objective: To assess the efficacy and safety of perampanel (PER) as primary monotherapy in patients aged 4-18 years old with epilepsy. Methods: A single-center, prospective, observational study was conducted from October 2021 to October 2023, to evaluate PER monotherapy's efficacy and safety as initial therapy for pediatric epilepsy. Changes in seizure frequency, safety, and retention rate were observed at 3, 6, 9, and 12 months after initiating PER primary monotherapy. Results: A total of 124 children aged 4-15 years (mean age = 8.25 +/- 2.50 years) were included in the Analysis Sets. The retention rates at 3, 6, 9, and 12 months were 88.71% (110/124), 84.68% (105/124), 78.26% (90/115), and 71.58% (68/95), respectively. Seizure freedom rates at 3, 6, 9, and 12 months were 85.45%, 79.09%, 76.24%, and 75.31%, respectively. The responder rates (>= 50% but <100%) at the same endpoints were 9.09%, 14.55%, 12.87%, and 7.41%, respectively. Seizure freedom rate of PER was independent of age at PER initiation, seizure onset age, gender, baseline frequency, seizure types, and family history of epilepsy (p > 0.05) but associated with duration of treatment (p = 0.001) and maintenance dose (p = 0.022). Additionally, 124 patients were included in the safety analysis set. The overall adverse event rate was 38.71% (48/124), with irritability (19 cases, 15.32%) and dizziness (18 cases, 14.52%) being the most common adverse effects. One patient discontinued PER monotherapy within 1 month due to unbearable itching of the skin. Significance: PER monotherapy as the primary anti-seizure medication (ASM) for pediatric epilepsy demonstrates high efficacy and safety in real-world clinical treatment. Patients who respond well to this drug and adhere to long-term treatment can achieve favorable seizure control. Furthermore, patients achieving seizure freedom with a relatively lower dose can opt for the same dose as the maintenance dose.