Relative Bioavailability and Bioequivalence of Brivaracetam 10 mg/mL Oral Solution and 50-mg Film-Coated Tablet

Narrative Review of Brivaracetam: Preclinical Profile and Clinical Benefits in the Treatment of Patients with Epilepsy

One third of patients with epilepsy will continue to have uncontrolled seizures despite treatment with antiseizure medications (ASMs). There is therefore a need to develop novel ASMs. Brivaracetam (BRV) is an ASM that was developed in a major drug discovery program aimed at identifying selective, high-affinity synaptic vesicle protein 2A (SV2A) ligands, the target molecule of levetiracetam. BRV binds to SV2A with 15- to 30-fold higher affinity and greater selectivity than levetiracetam. BRV has broad-spectrum antiseizure activity in animal models of epilepsy, a favorable pharmacokinetic profile, few clinically relevant drug-drug interactions, and rapid brain penetration. BRV is available in oral and intravenous formulations and can be initiated at target dose without titration. Efficacy and safety of adjunctive BRV (50-200 mg/day) treatment of focal-onset seizures was demonstrated in three pivotal phase III trials (NCT00490035/NCT00464269/NCT01261325), including in patients who had previously failed levetiracetam. Efficacy and safety of adjunctive BRV were also demonstrated in adult Asian patients with focal-onset seizures (NCT03083665). In several open-label trials (NCT00150800/NCT00175916/NCT01339559), long-term safety and tolerability of adjunctive BRV was established, with efficacy maintained for up to 14 years, with high retention rates. Evidence from daily clinical practice highlights BRV effectiveness and tolerability in specific epilepsy patient populations with high unmet needs: the elderly (≥ 65 years of age), children (< 16 years of age), patients with cognitive impairment, patients with psychiatric comorbid conditions, and patients with acquired epilepsy of specific etiologies (post-stroke epilepsy/brain tumor related epilepsy/traumatic brain injury-related epilepsy). Here, we review the preclinical profile and clinical benefits of BRV from pivotal trials and recently published evidence from daily clinical practice.

Pharmacokinetics, Safety, and Tolerability of Brivaracetam in Healthy Elderly Participants

The pharmacokinetics, metabolism, safety, and tolerability of the antiseizure medication brivaracetam (BRV) were characterized in 16 healthy elderly participants (8 men/8 women) aged 65-78 years who received a single 200-mg oral dose of BRV on day 1, followed by 200 mg twice daily from day 3 until day 12. BRV and three metabolites were determined in plasma and urine. Adverse events, vital signs, electrocardiograms, laboratory tests, general and neurological examinations, and psychometric rating scales were recorded at regular intervals. No clinically relevant changes or abnormalities were detected. The adverse events were similar to those observed in pivotal trials. Rating scales indicated transiently increased sedation and decreased alertness. BRV pharmacokinetics and metabolism were unchanged relative to younger populations. Based on our observations in this healthy elderly population receiving oral BRV 200 mg twice daily (twice the maximum recommended dose), dose reductions are not warranted relative to other, younger populations. Further investigations may be necessary in frail elderly populations aged >80 years.

Method Development and Validation of a Novel UHPLC Coupled with MS/MS System for the Estimation of Brivaracetam in Human (K2EDTA) Plasma Samples and its Application to Pharmacokinetic Study

Background:

Brivaracetam is a novel antiepileptic drug clinically approved for the treatment of partial onset seizures in adults and adolescents. It has some abuse potential and assigns to Schedule V category under the Controlled Substance Act by the Drug Enforcement Administration. It is essential to develop a faster, simple, and highly sensitive method for the quantification of Brivaracetam in human plasma by employing simple liquid-liquid extraction.

Objective:

The objective of this study is to develop and validate a novel UHPLC-MS/MS method for the estimation of brivaracetam in human plasma samples and application to pharmacokinetic study.

Methods:

An ultra-high-pressure liquid chromatography-tandem mass spectrometry method was developed and validated according to current regulatory guidelines for bioanalytical methods. Sample processing (50 μL) involved only a simple liquid-liquid extraction by ethyl acetate as extraction solvent. Brivaracetam-d7 was used as an internal standard. The chromatographic analysis was performed by a Unisol C18 (4.6 X 100 mm, 5μm) column using 0.1% formic acid in water/acetonitrile (20/80 V/V) as an isocratic mobile phase, at a flow rate of 1.0 mL/min with a run time of 2.2 min. Brivaracetam and its internal standard Brivaracetam D7 were detected and quantified in positive ion mode using multiple reaction monitoring transitions at m/z 213.100→168.100 and m/z 220.000→175.100, respectively. The developed method was applied to assess pharmacokinetic parameters like Cmax, Tmax, t1/2 and AUC for Brivaracetam in healthy, male, and adult humans.

Results:

The method was validated over a concentration range of 20.000 ng/mL to 4000. 000 ng/mL. Both intra- and inter-assay precision and accuracy were <15% for all quality control samples. No matrix effect was observed. Pharmacokinetic results showed that test formulation is bioequivalent with reference formulation.

Conclusion:

The present assay is faster, highly sensitive and simpler than previously published analytical reports for brivaracetam in human plasma samples and is suitable for pharmacokinetic evaluation of any marketed formulation.

Pharmacokinetics, safety, and tolerability of intravenous brivaracetam in pediatric patients with epilepsy: An open-label trial

Objective

To evaluate the pharmacokinetics, safety, and tolerability of brivaracetam (BRV) as 15‐min intravenous (IV) infusion and bolus (≤2‐min injection).

Methods

EP0065 (ClinicalTrials.gov: NCT03405714) was a Phase 2, multicenter, open‐label trial in patients ≥1 month to <16 years of age with epilepsy. Patients received up to 5 mg/kg/day BRV (not exceeding 200 mg/day). Enrollment was sequential by descending age, depending on safety review. Outcomes included BRV plasma concentrations before and after IV administration, treatment‐emergent adverse events (TEAEs), and discontinuations due to TEAEs.

Results

Fifty patients were enrolled, received BRV, and completed the trial. Twenty‐six patients (52.0%) received 15‐min infusions and 24 (48.0%) received bolus injections. Most patients (80.0%) received one IV dose. In the 15‐min infusion group, geometric mean (GeoMean) BRV concentrations 15 (±2) min (n = 21) and 3 h (±15 min) (n = 21) post dose were 1903.0 ng/mL (geometric coefficient of variation [GeoCV]: 60.7%) and 1130.3 ng/mL (58.8%), respectively. In the bolus group, GeoMean BRV concentrations 15 (±2) min (n = 19) and 3 h (±15 min) (n = 21) post dose were 1704.8 ng/mL (GeoCV: 74.5%) and 1383.9 ng/mL (85.0%), respectively. Overall, 14 patients (28.0%) had TEAEs (15‐min infusion: 8 [30.8%]; bolus: 6 [25.0%]), most commonly (≥5% of patients) somnolence (3 [6.0%]). Ten patients (20.0%) had drug‐related TEAEs (15‐min infusion: 6 [23.1%]; bolus: 4 [16.7%]). No patients discontinued due to TEAEs, and no deaths occurred.

Significance

IV BRV (up to 200 mg/day) was well tolerated in patients ≥1 month to <16 years of age, regardless of whether BRV was administered as 15‐min infusion or bolus. No unexpected safety or pharmacokinetic differences were observed between patients receiving 15‐min infusions or bolus, and plasma concentrations were in the expected range. Safety results were consistent with the known safety profile of oral BRV, with no new safety concerns identified.

Brivaracetam for the treatment of focal-onset seizures: pharmacokinetic and pharmacodynamic evaluations

INTRODUCTION

The goal of pharmacologic therapy with antiseizure medications (ASMs) is to achieve a seizure-free state with minimal side effects. About one third of patients treated with available ASMs continue to experience uncontrolled seizures. There is still need for new ASMs with enhanced effectiveness and tolerability.

AREAS COVERED

The present manuscript is based on an extensive Internet and PubMed search from 1999 to 2020. It is focused on the clinical and pharmacological properties of brivaracetam (BRV) in the treatment of epilepsy.

EXPERT OPINION

BRV is approved as add-on or monotherapy (in US) for the treatment of focal-onset seizures with or without secondary generalization. BRV is a high affinity synaptic vesicle glycoprotein 2A ligand, with 15-30-fold higher affinity than levetiracetam. The selectivity of BRV may be associated with fewer clinical adverse effects. BRV shares many of the pharmacokinetic characteristics of an ideal ASMs. Additionally, BRV has a low potential for clinically relevant drug-drug interactions. Its pharmacokinetic profile makes BRV a promising agent for the treatment of status epilepticus (SE). Although BRV is not approved for the treatment of SE, it has demonstrated promising preliminary results. Further studies are needed to explore the efficacy and tolerability of BRV in SE.

Randomized open-label trial of intravenous brivaracetam versus lorazepam for acute treatment of increased seizure activity

OBJECTIVE

The objective of the present trial was to assess efficacy and safety of intravenous (IV) brivaracetam (BRV) vs. lorazepam (LZP) in patients with epilepsy undergoing evaluation in an epilepsy monitoring unit (EMU) who experienced seizures requiring acute treatment.

METHODS

This was a phase 2, open-label, randomized, active-control, proof-of-concept trial (EP0087; NCT03021018). Patients (18-70 years) admitted to EMU were randomized 1:1:1 to single-dose bolus IV LZP (dose per investigator's practice), IV BRV 100 mg, or IV BRV 200 mg. Trial medication had to be administered within 30 min of qualifying seizure. Primary efficacy outcome was time to next seizure (clinical observation with electroencephalogram [EEG] confirmation) or to rescue medication use within 12 h of trial medication administration. Secondary outcomes included seizure freedom and rescue medication use within 12 h of trial medication administration. Safety and tolerability outcomes included treatment-emergent adverse events (TEAEs).

RESULTS

Overall, 46 patients were randomized, and 45 received trial medication for a qualifying seizure. Patients in the LZP arm had doses from 1 to 4 mg (median: 1 mg). Eleven of 45 patients had a seizure within 12 h of trial medication administration (LZP 5/15 [median time to next seizure: 5.55 h], BRV 100 mg 3/15 [5.97 h], BRV 200 mg 3/15 [3.60 h]). No patients received additional rescue medication to control their qualifying seizure. Most patients were seizure-free over 12 h (LZP 9/15 [60.0%], BRV 100 mg 12/15 [80.0%], BRV 200 mg 12/15 [80.0%]). Rescue medication use within 12 h was numerically higher for LZP (6/15 [40.0%]) vs. BRV 100 mg (1/15 [6.7%]) and vs. BRV 200 mg (2/15 [13.3%]). Treatment-emergent adverse events were reported by 5/16 (31.3%), 6/15 (40.0%), and 3/15 (20.0%) of LZP, BRV 100 mg, and BRV 200 mg patients; one LZP patient had a serious TEAE (seizure cluster). Most common TEAEs (≥10% of patients) were sedation and somnolence with LZP, and dizziness, headache, and nausea with BRV.

SIGNIFICANCE

Intravenous LZP, IV BRV 100 mg, and IV BRV 200 mg showed similar efficacy in controlling acute seizure activity in the EMU. Treatment-emergent adverse events were as expected for each medication. Although this trial should be interpreted with caution because of small patient numbers, it suggests a possible role of BRV in the acute treatment of increased seizure activity.

Safety and Tolerability of Adjunctive Brivaracetam in Pediatric Patients < 16 Years with Epilepsy: An Open-Label Trial

OBJECTIVE

This trial evaluated the short-term safety and tolerability, steady-state pharmacokinetics, and preliminary efficacy of brivaracetam oral solution in children aged 1 month to < 16 years with epilepsy.

METHODS

This was a phase IIa, open-label, single-arm, fixed three-step dose escalation trial of 3-weeks duration (N01263; NCT00422422). Patients were taking one to three concomitant antiepileptic drugs. Brivaracetam oral solution dosage, in two divided daily doses, was increased each week: approximately 0.8, 1.6, and 3.2 mg/kg/day for patients aged ≥ 8 years, and 1.0, 2.0, and 4.0 mg/kg/day for patients aged < 8 years.

RESULTS

Of the 100 patients enrolled, 90 (90.0%) completed the trial. The safety population comprised 99 patients. Treatment-emergent adverse events (TEAEs) considered drug related by the investigator were reported by 32/99 (32.3%) patients, most commonly (≥ 5%) somnolence (7.1%) and decreased appetite (6.1%). TEAEs were reported by 66/99 (66.7%) patients, most commonly (≥ 5%) convulsion, irritability, pyrexia, somnolence, and decreased appetite. In patients with a history of focal seizures with or without secondary generalization and no primary generalized seizures aged 4 to < 16 years (n = 34), drug-related TEAEs and TEAE incidences were 47.1% and 67.6%, respectively. Steady-state trough brivaracetam and brivaracetam metabolite plasma concentrations increased proportionally with dose. The ≥ 50% responder rates (all seizure types) were 21.3% (all patients, n = 80) and 36.4% (patients with focal seizures, aged 4 to < 16 years, n = 22).

CONCLUSIONS

This open-label trial in pediatric patients with epilepsy provides preliminary information that short-term, adjunctive brivaracetam treatment is well tolerated and effective. Plasma concentrations of brivaracetam and metabolites increased with increasing dose.

Brivaracetam in the treatment of epilepsy: a review of clinical trial data

Brivaracetam (BRV), an analog of levetiracetam (LEV), was discovered during a target-based rational drug discovery program that aimed to identify potent synaptic vesicle protein 2A (SV2A) ligands. Among the 12,000 compounds screened in vitro, BRV was found to have 15-30 times greater affinity for SV2A and faster brain permeability than LEV. Although preclinical and post-marketing studies suggest broad spectrum of efficacy, BRV is currently only approved as monotherapy and adjunctive therapy of focal-onset seizures in patients age 4 years and older. This review examines the use of BRV as add-on (5-200 mg/day) therapy for epilepsy with a particular emphasis on the six regulatory randomized clinical trialsinvolving 2399 participants. Participants receiving BRV add-on at doses of 50-200 mg/day were more likely to experience a 50% or greater reduction in seizure frequency (pooled risk ratio [RR]) 1.79 with 95% CI of 1.51-2.12) than those receiving placebo. Participants receiving BRV were also more likely to attain seizure freedom (57 [3.3%] vs 4 [0.5%]; RR 4.74, 95% CI 2.00-11.25) than those receiving placebo. In addition, BRV demonstrated a favorable safety profile similar to placebo across all BRV doses. Treatment emergent adverse events significantly associated with BRV were irritability, fatigue, somnolence, and dizziness. Post-hoc analysis of regulatory trials, post-marketing studies, and indirect comparison meta-analyses demonstrated equivalent efficacy and better tolerability of BRV when compared to other antiseizure drugs. Further, these studies appear to suggest that behavioral adverse events are likely to be less frequent and less severe with BRV than LEV. Therefore, switching to BRV may be considered for patients who have seizure control with LEV, but who cannot tolerate its behavioral adverse effects. In this setting, immediate switch from LEV to BRV at a 10:1-15:1 ratio without titration is feasible. Further research is needed to examine the long-term tolerability and efficacy of BRV as well as its role in the treatment of other types of epilepsies, particularly dementia-related epilepsy and brain tumor-related epilepsy.

A review of the pharmacology and clinical efficacy of brivaracetam

Brivaracetam (BRV; Briviact) is a new antiepileptic drug (AED) approved for adjunctive treatment of focal (partial-onset) seizures in adults. BRV is a selective, high-affinity ligand for synaptic vesicle 2A (SV2A) with 15- to 30-fold higher affinity than levetiracetam, the first AED acting on SV2A. It has high lipid solubility and rapid brain penetration, with engagement of the target molecule, SV2A, within minutes of administration. BRV has potent broad-spectrum antiepileptic activity in animal models. Phase I studies indicated BRV was well tolerated and showed a favorable pharmacokinetic profile over a wide dose range following single (10-1,000 mg) and multiple (200-800 mg/day) oral dosing. Three pivotal Phase III studies have demonstrated promising efficacy and a good safety and tolerability profile across doses of 50-200 mg/day in the adjunctive treatment of refractory focal seizures. Long-term data indicate that the response to BRV is sustained, with good tolerability and retention rate. BRV is highly effective in patients experiencing secondarily generalized tonic-clonic seizures. Safety data to date suggest a favorable psychiatric adverse effect profile in controlled studies, although limited postmarketing data are available. BRV is easy to use, with no titration and little drug-drug interaction. It can be initiated at target dose with no titration. Efficacy is seen on day 1 of oral use in a significant percentage of patients. Intravenous administration in a 2-minute bolus and 15-minute infusion is well tolerated. Here, we review the pharmacology, pharmacokinetics, and clinical data of BRV.

Evaluation of brivaracetam: a new drug to treat epilepsy

INTRODUCTION

High prevalence of therapy-resistant epilepsy demands development of anticonvulsants with new mechanisms of action. Brivaracetam is an analogue of levetiracetam which binds to the synaptic vesicle protein 2A (SV2A) and decreases release of excitatory neurotransmitters. Areas covered: Relevant published studies were searched for by predefined strategy in MEDLINE, EBSCO and SCINDEKS electronic databases. Brivaracetam is effective as adjunctive therapy for uncontrolled partial-onset seizures with or without secondary generalization in patients 16 years and older with epilepsy. It reduces baseline-adjusted focal seizure frequency per week from 7.3 to 12.8% over placebo. Adverse events rate in patients with brivaracetam is not higher than in patients with placebo. Expert opinion: Brivaracetam is an important step forward in the treatment of therapy-resistant partial-onset seizures with or without secondary generalization. Its development was systematic and targeted. Due to its efficacy and excellent safety profile, it is likely that brivaracetam will be often prescribed. In future, efficacy and safety of brivaracetam should be tested in monotherapy settings and also in the first-line therapy of partial-onset seizures.

Brivaracetam population pharmacokinetics in children with epilepsy aged 1 month to 16 years

Purpose

The aims of the study were to develop a population pharmacokinetic model of orally administered brivaracetam in paediatric patients and to provide dosing suggestions.

Methods

Analysis included 600 brivaracetam plasma concentrations from a phase 2a study (NCT00422422; N01263) in 96 paediatric patients with epilepsy aged 1 month to 16 years, taking one to three concomitant antiepileptic drugs (AEDs). Pharmacokinetic analysis was performed using non-linear mixed effects modelling, and a stepwise covariate search was used to determine factors influencing brivaracetam clearance. Simulations were performed to investigate dosing regimens.

Results

The final model consisted of first-order absorption, single compartment distribution and first-order elimination components with allometric scaling of clearance and volume using lean body weight and fixed allometric exponents. Co-administration with phenobarbital or carbamazepine was associated with a 29% (95%CI 17%/39%) and 32% (22%/42%) decrease in exposure, respectively. Co-administration with valproate was associated with an 11% (1%/23%) increase in exposure. Simulations demonstrated that the majority of children were predicted to have an exposure similar to that in adults, using an age-independent dosing regimen of 2.0 mg/kg bid with a maximum of 100 mg bid for body weight >50 kg.

Conclusions

A paediatric dose adaptation of 2.0 mg/kg twice daily with a maximum of 100 mg twice daily for body weight >50 kg is predicted to ensure steady-state plasma concentrations in the same range as in adult patients receiving 100 mg twice daily (highest recommended dose). Data suggest no need to change brivaracetam dosing when used concomitantly with carbamazepine, phenobarbital or valproate.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-017-2230-6) contains supplementary material, which is available to authorized users.