Abstracts

Rationale: Perampanel has a unique mechanism of action, AMPA receptor antagonist blocking glutamate at post synapses selectively (not interacting with NMDA or Kainate receptors) and non-competitively (does not compete with glutamate at the same binding site). It has been utilized in the U.S. since 2014 as an adjunctive therapy for patients with focal onset and primary generalized tonic-clonic seizures in 12 years and older. Perampanel has been approved for monotherapy use in patients with focal onset seizures in 2017. We were interested if perampanel early add on therapy would make a difference in seizure frequency reduction/28 days compared with late add-on therapy.  Methods: This is an observational study of 15 patients with refractory epilepsy treated with perampanel in a community setting over 517 days (with median 457 days) of time period. A total of 15 patients identified were based on total population sampling method. Descriptive statistics were performed for demographic variables. T-test was conducted to determine statistical difference of median percent reduction in seizure frequency/28 day. Seizure frequency was analyzed based on self-reported patients’ diary. Early add on perampanel was defined as 1st or 2nd add on perampanel in addition to concurrent AEDs (antiepileptic drug). Results: A total of 15 patients (Female: n= 12, 80%) were included in the analysis. Age ranged from 29 to 82 years (Mean±SD: 51.3±13.6). Average years of epilepsy diagnosed was 8.6 years, with average number of 2.7 concomitant AEDs when PER was initiated. Current perampanel dose ranged from 4 to 10mg/day with 4mg being the modal dose (46.7%) and median dose of 6mg. Baseline median seizure frequency was 15 per 28 days. Post perampanel median seizure frequency was zero (mean 0.3) per 28 days. In early add on perampanel group (n=8), baseline seizure frequency was 14.3±8.3 and 0.4 for post perampanel seizure frequency. For late add on perampanel group (n=7), baseline seizure frequency was 13.2±5.1 and 0.3 for post perampanel seizure frequency. There was no statistical difference between early add-on and late add-on perampanel group in seizure frequency reduction/28 days. However, the overall median percent seizure frequency reduction was 100% with seizure freedom of 87% in patients with refractory seizures. Conclusions: Perampanel demonstrated good efficacy in seizure frequency reduction in adult patients with focal with or without secondarily generalized seizures and primary generalized tonic clonic seizures regardless of early or late add on therapy. It is advised that larger randomized studies should be conducted to validate this study result. Funding: None