Abstracts

Rationale: Rationale: Perampanel (PER) is the first AMPA glutamate receptor antagonist licensed as add on therapy in refractory focal onset epilepsy. We present our own tertiary epilepsy centre experience with PER since its launch in the UK in October 2012. This is an extension of the previous audit of our first 60 focal onset epilepsy patients presented at the European Epilepsy Congress, Stockholm, June 2014. Its purpose is to share the “real world” experience with PER in a refractory cohort of patients.Methods: Methods: retrospective analysis of the data on safety and efficacy extracted from our database including patients treated with PER in our centre between Oct 2012 and 31.05.2015 (further cased included between June and October 2015 will be added). Four patients with generalised genetic epilepsy and frequent convulsive seizures not responding to other AEDs were also included. Many of our patients are surgical candidates and a few failed epilepsy surgery/ VNS.Results: Results: 130 patients (73 males, 53 females, mean age 44.3 +14.2 y; range 18-77y) treated with PER were analysed. Their mean age of epilepsy onset was 14.2+ 14(range 0.5-70 y) and mean epilepsy duration 24 + 15.5 y (range 2-76.5y). Common co-morbidities included learning difficulties (n=24; 18.5%), depression/ low mood (n=32, 25%) and anxiety (n=11; 9%). Historically, 101 patients suffered tonic – clonic seizures which were still active in 68. The mean number of concomitant AEDs was 2.43 + 0.91 (1-5) and the mean number of previous AEDs was 5.9 ( 2- 13). The range of doses of PER used was 2-12 mg od, mean 7 +2.94 mg. The mean duration of treatment was 314 + 243 days (median 264, range 5-870 days) with retention rate 58.5%. In 38.5% cases, PER was withdrawn, mostly due to side effects. Overall, side effects occurred in 48.5% of patients (leading to withdrawal in n=39 (30%) of all patients). The most common were dizziness (23%), behavioural change (14%), unsteadiness (11.5%). Seizure outcome data are reported for 97/130 patients who completed > 3 months follow up. Seizure freedom (all seizure types) was achieved in 10/97 (10.3%) with > 50% reduction in seizure frequency in further 23/97 (23.7%) patients. Subgroup analysis of patients with active tonic-clonic seizures (n=68): data was available for 63/68 patients with seizure freedom achieved in 20.6% and > 50% seizure reduction in further 17.4 %. Subgroup analysis for complex partial seizures as dominant seizure type (n=72): data was available for 68/72 with min 3 months follow up; seizure freedom was achieved in 12.5% and > 50% seizure reduction in further 18%.Conclusions: Conclusion: In our refractory cohort, who failed on previous multiple AEDs, PER rendered 10% of patients seizure free and produced > 50% reduction of seizures of all types in further 24%. Our data suggests a particularly good effect on secondary generalised tonic-clonic seizures which seems to be maintained after long follow up. However, side effects may be dose limiting with long term retention rate around 60% in our patient group.