32^nd European Neurology Congress

Perampanel is a once-daily oral anti-seizure drug for partial-onset seizures and primary generalised tonic-clonic seizures. We report the second interim analysis of the multicentre, non-interventional, Phase IV retrospective Study 506 (NCT03208660), to assess retention rate, safety and dosing experience of perampanel administered to patients with epilepsy during routine clinical care. Data were obtained from medical records of patients initiating perampanel after 1 January 2014. Primary endpoint is retention rate (proportion of patients remaining on perampanel; Safety Analysis Set [SAS]). Safety, effi cacy and dosing experience are secondary objectives. Th e interim SAS comprised 605 patients (55.9% female). At data cut-off (5 March 2018), 317 (52.4%) patients remained on perampanel; 285 (47.1%) had discontinued, primarily due to adverse event (AE; n=157 [26.0%]) and inadequate therapeutic effect (n=86 [14.2%]). Mean (standard deviation [SD]) cumulative duration of exposure to perampanel was 15.4 (13.9) months. Mean (SD) maximum perampanel dose was 6.5 (3.2) mg. Retention rates at 3, 6, 12, 18 and 24 months were 80.2% (n=479/597), 69.0% (n=392/568), 58.1% (n=288/496), 52.7% (n=216/410) and 49.8% (n=154/309), respectively. At Months 22-24: median reduction in seizure frequency per 28 days was 93.3% (n=27); 50% responder rate was 77.8% (n=21/27); 40.7% (n=11/27) of patients achieved seizure freedom. Treatment-emergent AEs (TEAEs) occurred in 304 (50.2%) patients, including dizziness (10.2%), aggression (6.1%) and irritability (5.0%). Serious TEAEs occurred in 14 (2.3%) patients, including 3 (0.5%) deaths. Favourable retention rates and sustained efficacy of perampanel for ≤2 years were demonstrated in patients with epilepsy treated during routine clinical care.