Adjunct Brivaracetam Shown to Significantly Reduce Partial-Onset Seizure Frequency
VANCOUVER, BC—Adjunctive treatment with brivaracetam (BRV), currently under regulatory review, is an effective and safe treatment for partial-onset (focal) seizures (POS), study authors presented at the 68th Annual AAN Meeting.
Dr. Pier Paolo Quarato, from the IRCCS Istituto Neurologico Mediterraneo, Pozzilli, Italy, and coauthors analyzed data from three Phase 3 randomized, placebo-controlled, double-blind, fixed-dose studies (NCT00490035, NCT00464269, NCT01261325) which assessed the efficacy of 50mg, 100mg, and 200mg of BRV daily or placebo. All study patients in the efficacy population (n=1,160) had POS uncontrolled by 1–2 antiepileptic medications and were not receiving concomitant levetiracetam. The safety population (n=1,262) included patients randomized to BRV 50–200mg daily or placebo who received at least 1 dose of the study drug with or without concomitant levetiracetam.
Data from the pooled analysis showed that adjunctive treatment with BRV led to a statistically significant percent reduction in POS over placebo in baseline-adjusted POS frequency per 28 days and ≥50% responder rate. Dr. Quarato added, "No overall dose-response effect was evident for either outcome, although efficacy was greater with the higher BRV dosages compared with BRV 50mg/day." Regarding secondary outcomes, response to BRV was higher than placebo without a clear dose-response effect.
For the 50mg/day group (n=161), there was a 19.5% reduction from baseline over placebo (P<0.01) and a 34.7% reduction from baseline (P<0.001). For the 100mg/day group (n=332), there was a 24.4% reduction from baseline over placebo and a 37.6% reduction from baseline (P<0.001 for both). For the BRV 200mg/day group (n=249), there was a 24.0% reduction from baseline over placebo and a 35.6% reduction from baseline (P<0.001 for both).
Each of the BRV treatment arms demonstrated a higher number of ≥50% responder rate when compared to the placebo group: 34.2% for BRV 50mg/day (P<0.01), 39.5% for BRV 100mg/day (P<0.001), and 37.8% for BRV 200mg/day (P<0.001) vs. 20.3% for placebo.
Safety was also evaluated for patients taking over ≥1 dose between 50–200mg/day with or without levetiracetam. Serious treatment-emergent adverse events (TEAEs) were reported by 3% and 2.8%, of the BRV and placebo groups, respectively. Most commonly reported adverse events included somnolence, dizziness, headache, and fatigue.
Study findings support that brivaracetam, a selective, high-affinity ligand for synaptic vesicle protein 2A, is effective and generally well tolerated at doses 50–200mg daily in adults with POS.