Which factors predict sustained seizure reduction with brivaracetam in focal epilepsy?

In patients with focal epilepsy, seizure frequency at baseline and the number of previous antiseizure medications (ASMs) used can predict sustained reduction in seizure frequency with adjunctive brivaracetam, according to data from the BRIVAFIRST study.

BRIVAFIRST was a retrospective study that included 994 adult patients prescribed adjunctive brivaracetam. Outcomes examined were sustained seizure response, sustained seizure freedom, and the rates of treatment discontinuation and adverse events (AEs). Baseline seizure frequency was stratified as <5, 5-20, and >20 seizures per month, while the number of prior antiseizure medications (ASMs) was categorized as <5 and ≥6.

Over the 12-month study period, sustained seizure response was observed in 45.8 percent, 39.3 percent, and 22.6 percent of patients with a baseline frequency of <5, 5-20, and >20 seizures per month, respectively (p<0.001). The corresponding proportions of patients with sustained seizure freedom were 23.4 percent, 9.8 percent, and 2.8 percent (p<0.001).

In the prior ASM category, 51.2 percent and 26.5 percent of patients with a history of 1-5 and ≥6 ASMs, respectively, achieved sustained seizure response (p<0.001). The corresponding proportions of patients with sustained seizure freedom were 24.7 percent and 4.5 percent (p<0.001).

Treatment discontinuation due to lack of efficacy occurred more frequently among patients with >20 vs <5 seizures per month (25.8 percent vs 9.3 percent; p<0.001) and among those with a prior use of ≥6 vs one to five ASMs (19.6 percent vs 12.2 percent; p=0.002).

No differences in the rates of brivaracetam withdrawal due to AEs and the rates of AEs were seen across the groups of patients defined according to the number of seizures at baseline and the number of prior ASMs.