Efficacy and Safety of Antiseizure Medication Brivaracetam Maintained in Asian Patients

Author(s):

Over a 12-week trial period, Asian patients treated with brivaracetam demonstrated efficacy and safety outcomes that were similar to other populations previously observed.

Brian Moseley, MD

Data from the randomized, double-blind, placebo-controlled phase 3 EP0083 study (NCT03083665) demonstrated the safety and effectiveness of brivaracetam (Briviact; UCB Pharma) in Asian patients with focal onset seizures. The findings add to the profile of the antiseizure medication (ASM), which was mainly studied in predominantly White/Caucasian populations.

Presented at the 2023 American Epilepsy Society (AES) annual meeting, held December 1-5, in Orlando, Florida, the study assessed brivaracetam in 50 mg and 200 mg doses among patients aged 16-80 years old from either Thailand, Japan, China, Philippines, Malaysia, Singapore, or Taiwan. Of the 449 randomized patients, 448 (mean age, 34.5 years; 53.8% female) received at least 1 dose and were included in the safety set (SS). The full analysis set (FAS) included 446 patients (50 mg: n = 151; 200 mg: n = 148; placebo: n = 147) with post-baseline seizure data.

Presented by Brian Moseley, MD, senior medical director at UCB Biosciences, the study spanned 12 weeks, with change in focal onset seizure frequency over a 28-day period as the primary end point. At the conclusion of the study, investigators recorded a 24.6% (P = .0004) and 33.3% greater reduction in focal seizure frequency for those on brivaracetam 50 mg and 200 mg, respectively, after 28 days. Response rate of at least 50% was recorded in 41.1% of those on brivaracetam 50 mg, 49.3% of those on 200 mg doses, and 19.0% of those on placebo.

Overall, mean duration of epilepsy was 16.6 (SD, 12.2) years, with more than half (51.8%; n = 231) of patients entering the study on 0-1 previous antiseizure medications. About one-third (32.3%) had used 2-4 and 15.9% had more than 5 previous ASMs. In the placebo, brivaracetam 50 mg and 200 mg groups, respectively, median baseline focal seizure frequency/28 days was 9.8, 9.0, and 7.8, respectively.

In terms of safety, the incidence of treatment-emergent adverse events (TEAEs) was similar between groups, with at least 1 recorded TEAE in 58.4% of patients on placebo, 57.0% on brivaracetam 50 mg, and 60.1% for those on brivaracetam 200 mg. Between these respective groups, 4.7%, 2.6%, and 3.4% of patients discontinued because of TEAEs. Serious TEAEs were reported by 0.7%, 1.3%, and 2.7% of patients in the placebo, brivaracetam 50 and 200 mg groups, respectively. Among those who received active treatment, the most common TEAEs were somnolence (50 mg: 9.9%; 200 mg: 18.9%) and dizziness (50 mg: 11.3%; 200 mg: 14.2%).

Brivaracetam is currently approved to treat temporal lobe epilepsy, focal impaired awareness or complex partial seizures, secondarily generalized seizures or bilateral tonic clonic seizure, and focal aware onset seizure. It is available in a tablet form, liquid solution, and intravenous formulation.

Recently, a 12-month, real-world study on the use of brivaracetam in patients with epilepsy from Australia, Europe, and the US were published in CNS Drugs. Also known as EXPERIENCE/EPD332, the study included patient records of 1644 adults who had at least 6 months of follow-up data. At 3, 6, and 12 months, respectively, seizure reductions of at least 50% were achieved by 32.1% (n = 619), 36.7% (n = 867), and 36.9% (n = 822) of patients, respectively. The study also showed a similar retention rate of brivaracetam between the 3 observed subgroups.²

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REFERENCES
1. Moseley B, Tiamkao S, Kaen K, et al. Efficacy and tolerability of adjunctive brivaracetam in Asian patients with focal onset seizures: a phase 3 randomized, placebo-controlled trial. Presented at: AES 2023; December 1-5; Orlando, FL. POSTER 1.286
2. Villanueva V, Laloyaux C, D’Souza W, et al. Effectiveness and tolerability of 12-month brivaracetam in the real world: EXPERIENCE, an international pooled analysis of individual patient records. CNS Drugs. 2023;37:819-835. doi:10.1007/s40263-023-01033-4