Abstracts

Rationale: Brivaracetam (BRV) is an adjunctive treatment for patients aged =16 years with focal onset seizures with and without secondary generalization. The synaptic vesicle protein 2A represents its main target, similar to Levetiracetam (LEV), but BRV has a higher selectivity and a 15- to 30-fold increased affinity. We aim to explore the effectiveness and tolerability of BRV as add-on treatment in patients with refractory epilepsy. Methods: Observational study of a Unicenter prospective cohort treated with add-on BRV. Data collected from patient clinical files between February 2016 and May 2018. The analysis was performed using appropriate descriptive statistical methods. Qualitative variables are presented as absolute frequencies and percentages and quantitative variables as a median and interquartile range (IQR:p25;p75) or as a mean and standard deviation based on their distribution.  Results:  We analyzed 53 patients (27 males; 26 females) with a median age of 40.6 years and an average epilepsy duration of 24.6 years (IQR:34.7-16.9). Fifty (94.3%) patients had a median number of concomitant antiepileptic drugs (AEDs) =2 at the time of initiating BRV. All patients exhibited focal seizures and 28.3% (n=15) secondary generalized seizures. The most common dose was 200 mg daily (IQR: 50). The median follow-up duration was 10.9 months (IQR:13.6-6.1), and overall retention rate was 66%. The rate of responders (defined as =50% seizure reduction from baseline seizure frequency) during follow-up was 32.1% (n = 17). Secondary generalized seizures were controlled in 93.3% (n=14) of the patients. Three (5.6%) patients became seizure-free. Eighteen (33.9%) patients had an overnight switch from LEV to BRV and only 3 had seizure worsening and took LEV again. The most frequently reported side effects were somnolence, fatigue, irritability, nausea, headache, dizziness and mood change. In 9 (53%) cases, adverse effects were solved with dose reduction or slower titration and treatment was not discontinued. Twelve patients discontinued BRV due to lack of efficacy and 5 due to low tolerability.  Conclusions: In our drug resistant epilepsy cohort, BRV showed a similar response rate as reported in pivotal trials, with a significant role in the control of secondarily generalized seizures. BRV presents a favorable side effect profile and broadens the therapeutic options in pharmacoresistant epilepsy. Funding: No funding was received in support of this abstract.