Brivaracetam as add-on treatment in focal epilepsy: A real-world time-based analysis

Investigating clinical pharmacokinetics of brivaracetam by using a pharmacokinetic modeling approach

The development of technology and the processing speed of computing machines have facilitated the evaluation of advanced pharmacokinetic (PK) models, making modeling processes simple and faster. The present model aims to analyze the PK of brivaracetam (BRV) in healthy and diseased populations. A comprehensive literature review was conducted to incorporate the BRV plasma concentration data and its input parameters into PK-Sim software, leading to the creation of intravenous (IV) and oral models for both populations. The developed physiologically based pharmacokinetic (PBPK) model of BRV was then assessed using the visual predictive checks, mean observed/predicted ratios (Robs/pre), and average fold error for PK parameters including the maximum systemic concentration (Cmax), the area under the curve at time 0 to t (AUC0-∞), and drug clearance (CL). The PBPK model of BRV demonstrated that mean Robs/pre ratios of the PK parameters remained within the acceptable limits when assessed against a twofold error margin. Furthermore, model predictions were carried out to assess how AUC0-∞ is affected following the administration of BRV in individuals with varying degrees of liver cirrhosis, ranging from different child-pugh (CP) scores like A, B, and C. Moreover, dose adjustments were recommended by considering the variations in Cmax and CL in various kidney disease stages (mild to severe).

Adjunctive brivaracetam and sustained seizure frequency reduction in very active focal epilepsy

OBJECTIVE

This study aimed to explore the effectiveness of brivaracetam (BRV) according to baseline seizure frequency and past treatment history in subjects with focal epilepsy who were included in the Brivaracetam Add-On First Italian Network Study (BRIVAFIRST).

METHODS

BRIVAFIRST was a 12-month retrospective, multicenter study including adults prescribed adjunctive BRV. Study outcomes included sustained seizure response (SSR), sustained seizure freedom (SSF), and the rates of treatment discontinuation and adverse events (AEs). Baseline seizure frequency was stratified as <5, 5-20, and >20 seizures per month, and the number of prior antiseizure medications (ASMs) as <5 and ≥6.

RESULTS

A total of 994 participants were included. During the 1-year study period, SSR was reached by 45.8%, 39.3%, and 22.6% of subjects with a baseline frequency of <5, 5-20, and >20 seizures per month (p < .001); the corresponding figures for the SSF were 23.4%, 9.8%, and 2.8% (p < .001). SSR was reached by 51.2% and 26.5% participants with a history of 1-5 and ≥6 ASMs (p < .001); the corresponding rates of SSF were 24.7% and 4.5% (p < .001). Treatment discontinuation due to lack of efficacy was more common in participants with >20 seizures compared to those with <5 seizures per month (25.8% vs. 9.3%, p < .001), and in participants with history of ≥6 prior ASMs compared to those with history of 1-5 ASMs (19.6% vs. 12.2%, p = .002). There were no differences in the rates of BRV withdrawal due to AEs and the rates of AEs across the groups of participants defined according to the number of seizures at baseline and the number of prior ASMs.

SIGNIFICANCE

The baseline seizure frequency and the number of previous ASMs were predictors of sustained seizure frequency reduction with adjunctive BRV in subjects with focal epilepsy.

BRIVEST: A 'real-world' observational, single-centre study investigating the efficacy, safety and tolerability of Brivaracetam

OBJECTIVE

Via measures of efficacy, tolerability, and safety, this open-label, single-center study assessed the overall effectiveness of Brivaracetam (BRV) for the treatment of epilepsy in the context of 'real-world' clinical practice.

METHODS

Unselected consecutive patients were recruited and stratified into 3 cohorts with either fully prospective, fully retrospective or mixed data collection, dependent on whether their BRV prescriptions were historical, current, or pending. Prospective data were obtained at baseline, 3 and 6 months, and at 6-month intervals thereafter, from patient interviews and seizure diaries, and retrospective data from medical records. Efficacy variables were derived from seizure-related changes, and tolerability and safety variables from reported treatment-emergent adverse events (TEAEs), BRV withdrawal, and changes to questionnaire scores. Additionally, we investigated treatment outcomes for those with previous levetiracetam (LEV) use, a history of psychiatric comorbidity, a learning disability, and of older age.

RESULTS

One hundred and nine patients (58.7% female, mean age 42 years, range: 18 to 72) were included, 59 with prospective follow-up for a minimum of 6 (47 patients, excluding those who withdrew) and a maximum of 24 months (2 patients). Of the full cohort, 87.2% had drug-resistant epilepsy. Retention: At the study end, the median treatment duration was 384 days (range: 6 to 1514 days), and BRV retention was 68.8%. Kaplan-Meier survival functions predicted retention rates of 74.0% and 70.0% at 6 and 12 months respectively.

EFFICACY

At the last follow-up, there was a ≥ 50% responder rate of 30.8%, with 12.1% seizure-free. Seizure frequency categories improved in 31.4% of patients, remained the same in 44.2%, and worsened in 24.4%. Monthly tonic-clonic seizure frequency had significantly decreased, and of those reporting these seizures, 58.3% showed reductions and 25.0% showed complete tonic-clonic seizure freedom.

TOLERABILITY

91.7% of patients reported at least 1 TEAE, with fatigue (30.3%), irritability (29.4%), and depression/low mood (28.4%) as the most common. Only 58.4% of all TEAEs were persistent. Brivaracetam discontinuation due to side effects occurred in 27.5% of the cohort. Depression and anxiety scores remained stable over time, and quality-of-life scores improved. Subgroups: Measures of BRV efficacy and tolerability did not differ according to previous LEV exposure. Tolerability profiles of those with learning disabilities, histories of psychiatric comorbidities, and older age did not greatly differ from the rest of the cohort. Of note, specific history of depression predicted the reporting of suicidal ideation.

CONCLUSION

The BRIVEST study provides real-world evidence of the effectiveness of BRV, suggesting that neither drug-resistant epilepsy nor previous LEV failure should preclude its use. Furthermore, BRV appears to be well-tolerated, even among those from vulnerable patient populations.

Retention of brivaracetam in adults with drug-resistant epilepsy at a single tertiary care center

INTRODUCTION

Brivaracetam (BRV) is licensed as an adjunctive treatment for focal epilepsy. We describe our clinical experience with BRV at a large UK tertiary center.

METHODS

Adults initiated on BRV between July 2015 and July 2020 were followed up until they discontinued BRV or September 2021. Data on epilepsy syndrome, duration, seizure types, concomitant and previous antiseizure medication (ASM) use, BRV dosing, efficacy, and side effects were recorded. Efficacy was categorized as temporary (minimum three months) or ongoing (at last follow-up) seizure freedom, ≥50% seizure reduction, or other benefits (e.g., no convulsions or daytime seizures). Brivaracetam retention was estimated using Kaplan-Meier survival analysis.

RESULTS

Two-hundred people were treated with BRV, of whom 81% had focal epilepsy. The mean (interquartile range [IQR]) follow-up time was 707 (688) days, and the dose range was 50-600 mg daily. The mean (IQR) of the previous number of used ASMs was 6.9 (6.0), and concomitant use was 2.2 (1.0). One-hundred and eighty-eight people (94%) had previously discontinued levetiracetam (LEV), mainly due to side effects. 13/200 (6.5%) were seizure free for a minimum of six months during treatment, and 46/200 (23%) had a ≥50% reduction in seizure frequency for six months or more. Retention rates were 83% at six months, 71% at 12 months, and 57% at 36 months. Brivaracetam was mostly discontinued due to side effects (38/75, 51%) or lack of efficacy (28/75, 37%). Concomitant use of carbamazepine significantly increased the hazard ratio of discontinuing BRV due to side effects (p = 0.006). The most commonly reported side effects were low mood (20.5%), fatigue (18%) and aggressive behavior (8.5%). These side effects were less prevalent than when the same individuals took LEV (low mood, 59%; aggressive behavior, 43%). Intellectual disability was a risk factor for behavioral side effects (p = 0.004), and a pre-existing mood disorder significantly increased the likelihood of further episodes of low mood (p = 0.019).

CONCLUSIONS

Brivaracetam was effective at a broad range of doses in managing drug-resistant epilepsy across various phenotypes, but less effective than LEV in those who switched due to poor tolerability on LEV. There were no new tolerability issues, but 77% of the individuals experiencing side effects on BRV also experienced similar side effects on LEV.

Adjunctive Brivaracetam in Older Patients with Focal Seizures: Evidence from the BRIVAracetam add‑on First Italian netwoRk Study (BRIVAFIRST)

Background

The management of epilepsy in older adults has become part of daily practice because of an aging population. Older patients with epilepsy represent a distinct and more vulnerable clinical group as compared with younger patients, and they are generally under-represented in randomized placebo-controlled trials. Real-world studies can therefore be a useful complement to characterize the drug’s profile. Brivaracetam is a rationally developed compound characterized by high-affinity binding to synaptic vesicle protein 2A and approved as adjunctive therapy for focal seizures in adults with epilepsy.

Objective

The aim of this study was to assess the 12-month effectiveness and tolerability of adjunctive brivaracetam in older patients (≥65 years of age) with epilepsy treated in a real-world setting.

Methods

The BRIVAFIRST (BRIVAracetam add-on First Italian netwoRk STudy) was a 12-month retrospective multicenter study including adult patients prescribed adjunctive brivaracetam. Effectiveness outcomes included the rates of seizure response (≥50% reduction in baseline seizure frequency), seizure freedom, and treatment discontinuation. Safety and tolerability outcomes included the rate of treatment discontinuation due to adverse events and the incidence of adverse events. Data were compared for patients aged ≥65 years of age (‘older’) vs those aged <65 years (‘younger’).

Results

There were 1029 patients with focal epilepsy included in the study, of whom 111 (10.8%) were aged ≥65 years. The median daily dose of brivaracetam at 3 months was 100 [interquartile range, 100–175] mg in the older group and 100 [100–200] mg in the younger group (p = 0.036); it was 150 [100–200] mg in both groups either at 6 months (p = 0.095) or 12 months (p = 0.140). At 12 months, 49 (44.1%) older and 334 (36.4%) younger patients had a reduction in their baseline seizure frequency by at least 50% (p = 0.110), and the seizure freedom rates were 35/111 (31.5%) and 134/918 (14.6%) in older and younger groups, respectively (p < 0.001). During the 1-year study period, 20 (18.0%) patients in the older group and 245 (26.7%) patients in the younger group discontinued brivaracetam (p = 0.048). Treatment withdrawal because of insufficient efficacy was less common in older than younger patients [older: n = 7 (6.3%), younger: n = 152 (16.6%); p = 0.005]. Adverse events were reported by 24.2% of older patients and 30.8% of younger patients (p = 0.185); the most common adverse events were somnolence, nervousness and/or agitation, vertigo, and fatigue in both study groups.

Conclusions

Adjunctive brivaracetam was efficacious, had good tolerability, and no new or unexpected safety signals emerged when used to treat older patients with uncontrolled focal seizures in clinical practice. Adjunctive brivaracetam can be a suitable therapeutic option in this special population.

Long-term efficacy, tolerability, and retention of brivaracetam in epilepsy treatment: A longitudinal multicenter study with up to 5 years of follow-up

OBJECTIVE

This study was undertaken to evaluate the long-term efficacy, retention, and tolerability of add-on brivaracetam (BRV) in clinical practice.

METHODS

A multicenter, retrospective cohort study recruited all patients who initiated BRV between February and November 2016, with observation until February 2021.

RESULTS

Long-term data for 262 patients (mean age = 40 years, range = 5-81 years, 129 men) were analyzed, including 227 (87%) diagnosed with focal epilepsy, 19 (7%) with genetic generalized epilepsy, and 16 (6%) with other or unclassified epilepsy syndromes. Only 26 (10%) patients had never received levetiracetam (LEV), whereas 133 (50.8%) were switched from LEV. The length of BRV exposure ranged from 1 day to 5 years, with a median retention time of 1.6 years, resulting in a total BRV exposure time of 6829 months (569 years). The retention rate was 61.1% at 12 months, with a reported efficacy of 33.1% (79/239; 50% responder rate, 23 patients lost-to-follow-up), including 10.9% reported as seizure-free. The retention rate for the entire study period was 50.8%, and at last follow-up, 133 patients were receiving BRV at a mean dose of 222 ± 104 mg (median = 200, range = 25-400), including 52 (39.1%) who exceeded the recommended upper dose of 200 mg. Fewer concomitant antiseizure medications and switching from LEV to BRV correlated with better short-term responses, but no investigated parameters correlated with positive long-term outcomes. BRV was discontinued in 63 (24%) patients due to insufficient efficacy, in 29 (11%) for psychobehavioral adverse events, in 25 (10%) for other adverse events, and in 24 (9%) for other reasons.

SIGNIFICANCE

BRV showed a clinically useful 50% responder rate of 33% at 12 months and overall retention of >50%, despite 90% of included patients having previous LEV exposure. BRV was well tolerated; however, psychobehavioral adverse events occurred in one out of 10 patients. Although we identified short-term response and retention predictors, we could not identify significant predictors for long-term outcomes.