Abstracts

Rationale: We aim to compare the retention rate (RR) (primary endpoint), effectiveness, and tolerability (secondary endpoints) of perampanel (PER) at one-year in different stages of focal epilepsies treatment. Methods: Multicentre, retrospective, 1-year, observational study in two groups of adult patients with focal epilepsy, highly refractory (HRG) vs. first add-on (FAG), treated with PER. Data from clinical records were analyzed at baseline, 3, 6, 9, and 12 months to evaluate the RR, tolerability, and effectiveness of PER in both groups. Results: Fifty-eight patients were included, 13 in the FAG, mean age 37,5 years (18-69), 45 in the HRG, mean age 46,3 years (19-72), mean of 3 (1-5) antiepileptic drugs (AED) at baseline. At 1-year, the overall RR was 84,6% in the FAG and 66,7% in the HRG (p=0,181), with mean doses of PER being 5,52mg and 6,26mg, respectively; in patients with secondarily generalized tonic-clonic seizures (SGTCS; n=21), the RR was 100% in the FAG, 91,7% in the HRG. PER discontinuation was due to adverse events (AE) (n=5) or lack of effectiveness (n=12, 80% in the HRG). AE occurred in 53,4% of patients (61,5% in the FAG, 51,1% in the HRG; p=0,5) and were mild in 87,1% of patients, the commonest being dizziness (67,7%). At 1-year, 81,8% (9/11) of FAG patients were seizure-free, 21,2% in the HRG (p=0.009); the responder rate was similar in both groups (18,2%). Regarding SGTCS, 77,8% (7/9) in the FAG were seizure-free, 45,6% in the HRG. Conclusions: This is the first real-world study comparing RR, tolerability and effectiveness of PER in two different stages of epilepsy treatment. Although the retention rate and seizure-freedom at 1 year are significantly higher in the FAG compared to HRG, PER is a very well tolerated AED and showed effectiveness even in a HRG of adult patients with focal epilepsies, particularly in patients with SGTCS. Funding: No funding