Abstracts

Rationale: Clinical data on the use of brivaracetam (BRV) in daily practice are still limited. The objective of this study was to evaluate the efficacy and tolerability of an adjunctive treatment with BRV in adults with highly refractory focal onset seizures (FOS). Methods: We retrospectively collected data from adult patients included in the BRV medical need program of UCB at Erasme hospital (Brussels) between July 2016 and March 2018. Data on seizure frequency were collected before the introduction of BRV and at last follow-up. Efficacy on seizure control was assessed by 50% responder rate. Tolerability was assessed as occurrence of treatment-emergent side effects. Results: Data from 14 patients were analyzed (Median age: 52 years, range: 20-67 years, 7 female) with a mean exposure to BRV of 8 months (range: 0.75-17 months). All patients were diagnosed with focal epilepsy and 5 (36%) had FOS evolving to bilateral tonic-clonic seizures. The median number of prior failed antiepileptic drugs (AEDs) was 10.5 (range: 6-16 AEDs), and all patients had been previously exposed to levetiracetam (LEV). Efficacy data at last follow-up show a 50% responder rate of 14% (n=2) with one patient being seizure free (7%). Treatment-related side effects were observed in 7/14 patients (50%). The most common were psychiatric and behavioral side effects (PBSEs), observed in 6/14 patients (43%) and leading to BRV withdrawal in 5/14 patients (36%). They included aggressiveness (n=5), depression (n=2), anxiety (n=1) and suicidal ideations (n=1).Among these 6 patients, 4 (67%) had psychiatric comorbidities prior to BRV administration. PBSEs rate in patients with known psychiatric comorbidities was 4/5 (80%), which did not significantly differ from patients without psychiatric comorbidities (2/9 [22%]), likely due to the lack of power of our study (OR: 11.0; IC95%: 0.6-779.2; p=0.091). Kaplan-Meier survival curves showed an overall retention rate of 72% at 6 months and 43% at 1 year, with a median retention time of 9 months. Six-month retention rate in patients with and without psychiatric comorbidities was 60% and 78%, respectively. Comparison of survival curves did not show any significant difference between groups (Log-Rank p=0.29). Overall, 8/14 patients (57%) discontinued BRV, mainly due to PBSEs. Conclusions: In this population of highly refractory patients previously exposed to LEV, long-term response to BRV is low and, particularly in patients with psychiatric comorbidities, PBSEs are frequent. Funding: None