Five-Year Retention of Perampanel and Polytherapy Patterns: 328 Patients From a Single Center in South Korea

Abstract

Background and Purpose Perampanel (PER) is an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid antagonist used to treat focal and generalized epilepsy. Comprehen-sive data from real-world settings with long-term follow-ups are still scarce. This study aimed to determine the factors related to PER retention and the polytherapy pattern with PER. Methods We reviewed all patients with epilepsy with a history of PER prescription during 2008–2017 and over a follow-up of >3 years. PER usage patterns and associated factors were analyzed. Results Among the 2,655 patients in the cohort, 328 (150 females, 178 males) were enrolled. The ages at onset and diagnosis were 21.1±14.7 years and 25.6±16.1 years (mean±standard deviation), respectively. The age at the first visit to our center was 31.8±13.8 years. Seizure types were focal, generalized, and unknown onset in 83.8%, 15.9%, and 0.3% of patients, re-spectively. The most common etiology was structural (n=109, 33.2%). The maintenance dura-tion of PER was 22.6±19.2 months (range=1–66 months). The initial number of concomitant antiseizure medications was 2.4±1.4 (range=0–9). The most common regimen was PER plus levetiracetam (n=41, 12.5%). The median number of 1-year seizures before PER usage was 8 (range=0–1,400). A seizure reduction of >50% was recorded in 34.7% of patients (52.0% and 29.2% in generalized and focal seizures, respectively). The 1-, 2-, 3-, 4-, and 5-year retention rates for PER were 65.3%, 50.4%, 40.4%, 35.3%, and 21.5%, respectively. A multivariate analysis indicated that lower age at onset was associated with longer retention (p=0.01). Conclusions PER was safely used in patients with diverse characteristics and was maintained for a long time in a real-world setting, especially in patients with a lower age at onset. t © 2023 Korean Neurological Association.