Advancing pharmacologic treatment options for pharmacologic treatment options for children with epilepsy

Introduction: The pharmacological management of epilepsy is continually modified by the increase in our knowledge about the efficacy and the safety on antiepileptic drugs.

Areas covered: This review covers the published data (2010–2015) on the pharmacological management of epilepsy in children and adolescent. We review the data from the most recent randomized controlled and open-label trials.

Expert opinion: Even if there is an increasing number of antiepileptic drugs approved for focal seizure in children and adolescent with epilepsy, each new approval would be considered as a significant addition to the current therapeutic options. Refractory epilepsy with focal seizure should not be regarded as a single disease but as numerous various patients. Because most of evidence of efficacy is primarily from placebo-controlled trials, there is no evidence to choose a treatment based on efficacy. In case of focal seizure, we explain how possible cognitive impact, mechanisms of action, pharmacologic characteristics and side effect profile are the factors taken into an account to propose a treatment. In case of childhood absence epilepsy, there are evidences showing the ethosuximide should be the first line treatment. Finally, we stress that trials in the pediatric epilepsy syndromes are required to propose better evidence-based pharmacological management.     

吡仑帕奈片在健康受试者中的生物等效性研究

目的 考察在空腹、餐后条件下健康受试者口服吡仑帕奈片受试制剂和参比制剂体内吡仑帕奈的血药浓度和药动学参数,评价吡仑帕奈片的生物等效性和安全性。方法 采用健康受试者在空腹、餐后的单中心、单剂量、两制剂、随机、开放、两周期、自身交叉对照试验设计的人体生物等效性研究。空腹和餐后组健康受试者分别口服4 mg吡仑帕奈片受试制剂或参比制剂,采用HPLC-MS/MS法测定血浆中吡仑帕奈的浓度,药动学使用Phoenix Win Nonlin 8.1软件的非房室模型计算各受试者的药动学参数,使用SAS 9.4软件进行临床安全性统计分析。结果 空腹、餐后试验吡仑帕奈片受试试剂和参比试剂的最大血药浓度(C_max)分别为(181.20±46.14)、(168.60±47.98),(130.44±28.59)、(139.15±39.99)ng/m L,药时曲线面积(AUC_0-t)分别为(7 587.46±2 975.40)、(7 485.88±2 910.03),(7 820.54±3 229.68)、(7 528.88±2 325.94)h·ng/m L。两组吡仑帕...     

One‐year clinical experience of perampanel in Spain: a multicentre study of efficacy and tolerability

Perampanel, a non‐competitive antagonist of the α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole‐propionic acid receptors, is the most recent antiepileptic drug available in Spain, marketed in January 2014. It was initially approved by the European Medicines Agency as adjunctive treatment for partial‐onset seizures in patients 12 years and older, but recently also for primary generalized tonic‐clonic seizures. Although clinical trials provide essential information about the drug, they do not reflect daily clinical practice. This retrospective study shows the initial experience with perampanel in 11 Spanish hospitals during its first year post‐commercialisation. All patients who started perampanel treatment were included, but efficacy and tolerability were only assessed in those patients with a minimum follow‐up period of six months. In total, 256 patients were treated with perampanel before September 2014, and 253 had an observational period of one year. After six months, 216/256 patients (84%) continued on perampanel and 180/253 (71.1%) completed one year of treatment. The mean number of previous antiepileptic drugs used was 6.83 and the median number of concomitant antiepileptic drugs was 2. The mean perampanel dose was 7.06 mg and 8.26 mg at six and 12 months, respectively. The responder rate was 39.5% and 35.9% at both follow‐up points, respectively. Adverse events were experienced by 91/253 (35.5%) and resulted in withdrawal in 37 (14.6%). The most common adverse events were somnolence, dizziness, and irritability. We found no significant differences between concomitant use of enzyme‐inducing and non‐inducing antiepileptic drugs, regarding efficacy, adverse effects, or withdrawals. Irritability was not influenced by concomitant use of levetiracetam, relative to other drugs, but was more frequently observed in patients with a history of psychiatric problems or learning disabilities.     

Safety and efficacy of perampanel in advanced Parkinson's disease: A randomized,placebo‐controlled study

Perampanel, a novel, noncompetitive, selective AMPA‐receptor antagonist demonstrated evidence of efficacy in reducing motor symptoms in animal models of Parkinson's disease (PD). We assessed the safety and efficacy of perampanel for treatment of “wearing off” motor fluctuations in patients with PD. Patients (N = 263) were randomly assigned to once‐daily add‐on 0.5, 1, or 2 mg of perampanel or placebo. The primary objective was to determine whether there was a dose‐response relationship for efficacy among the 3 perampanel doses and placebo. The primary efficacy endpoint for each treatment was measured as the least‐squares (LS) mean change from baseline to week 12 in percent “off” time reduction during the waking day, as recorded by patient diaries. The primary efficacy analysis was a 1‐sided Williams test for dose‐response trend at the 0.025 level of significance. At week 12, dose‐response trends, as determined by the Williams test, were not statistically significant for LS mean reduction in percent “off” time during the waking day (P = 0.061, with significance defined as P ≤ 0.025). The 2 higher perampanel doses (ITT population; n = 258) produced nonsignificant reductions from baseline to week 12 in percent “off” time during the waking day versus placebo (7.59%, P= 0.421 [1 mg], 8.60%, P = 0.257 [2 mg] versus 5.05% [placebo]; significance for pairwise comparisons defined as P ≤ 0.05). There were no significant changes in dyskinesia or cognitive function in any perampanel group versus placebo. Adverse events were similar across treatment groups. Perampanel treatment was well tolerated and safe, but failed to achieve statistical significance in primary and secondary endpoints. © 2010 Movement Disorder Society     

The AMPAR antagonist perampanel protects the neurovascular unit against traumatic injury via regulating Sirt3

IntroductionPerampanel is a highly selective and noncompetitive α‐amino‐3 ‐hydroxy‐5‐methyl‐4‐isoxazole propionate receptor (AMPAR) antagonist, which has been used as an orally administered antiepileptic drug in more than 55 countries. Recently, perampanel was shown to exert neuroprotective effects in hemorrhagic and ischemic stroke models via regulating blood–brain barrier (BBB) function.AimHere, the protective effects of perampanel were investigated in an in vitro neurovascular unit (NVU) system established using a triple cell co‐culture model (neurons, astrocytes, and brain microvascular endothelial cells) and in an in vivo traumatic brain injury (TBI) model.ResultsNeurons in the NVU system exhibit a more mature morphological phenotype compared with neurons cultured alone, and the co‐culture system mimicked an impermeable barrier in vitro. Perampanel protects the NVU system against traumatic and excitotoxic injury, as evidenced by reduced lactate dehydrogenase (LDH) release and apoptotic rate. Treatment with perampanel attenuated lipid peroxidation and expression of inflammatory cytokines. In addition, perampanel increased Sirt3 protein expression, enhanced the activities of mitochondrial enzyme IDH2 and SOD2, and preserved BBB function in vitro. Knockdown of Sirt3 using specific siRNA (Si‐Sirt3) partially reserved the effects of perampanel on neuronal injury and BBB function. Treatment with perampanel in vivo attenuated brain edema, preserved neurological function, inhibited apoptosis and microglia activation after TBI. Furthermore, perampanel increased the expression of Sirt3 and preserved BBB function after TBI. The effect of perampanel on BBB function and brain edema was abolished by knockdown of Sirt3 in vivo.ConclusionOur results indicate that the noncompetitive AMPAR antagonist perampanel protects the NVU system and reduces brain damage after TBI via activating the Sirt3 cascades.     

Perampanel for the treatment of primary generalized tonic-clonic seizures in idiopathic generalized epilepsy

Introduction: The non-competitive α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) – receptor antagonist perampanel (PER) was approved in 2015 for treatment of primary generalized tonic-clonic seizures (pGTCS). The aim of this narrative review is to summarize available data on pharmacological properties, efficacy and tolerability of PER in pGTCs.

Areas covered: Data sources included MEDLINE, EMBASE, Google Scholar and ClinicalTrials.gov, conference proceedings of the ILAE congresses and the most recent conference proceedings of the American Epilepsy Society (2013 to 2015).

Expert opinion: A placebo-controlled clinical phase III study including 164 patients (≥ 12 years) with pGTCS in idiopathic generalized epilepsies (IGE) demonstrated efficacy of PER in reducing pGTCS with good tolerability profile, and without aggravating absence seizures or myoclonic seizures. Dizziness, the main adverse event (AE), can be avoided by bedtime administration. Psychiatric AEs ranging from mild depression to aggression and suicidal attempts should be especially monitored in patients with a history of psychiatric disorders. Co-administration of enzyme inducing antiepileptic drugs (AEDs) might decrease PER plasma levels and make dose adjustment necessary. A reduced efficacy of progesterone-containing oral contraceptives should be considered when administering PER to young women. There is lack of evidence on PER treatment in pregnancy. Although no teratogenic effects were observed in animal models, PER is not recommended for women of childbearing age without contraception.     

Perampanel as precision therapy in rare genetic epilepsies

Objective

Perampanel, an antiseizure drug with α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist properties, may have a targeted effect in genetic epilepsies with overwhelming glutamate receptor activation. Epilepsies with loss of γ-aminobutyric acid inhibition (e.g., SCN1A), overactive excitatory neurons (e.g., SCN2A, SCN8A), and variants in glutamate receptors (e.g., GRIN2A) hold special interest. We aimed to collect data from a large rare genetic epilepsy cohort treated with perampanel, to detect possible subgroups with high efficacy.

Methods

This multicenter project was based on the framework of NETRE (Network for Therapy in Rare Epilepsies), a web of pediatric neurologists treating rare epilepsies. Retrospective data from patients with genetic epilepsies treated with perampanel were collected. Outcome measures were responder rate (50% seizure reduction), and percentage of seizure reduction after 3 months of treatment. Subgroups of etiologies with high efficacy were identified.

Results

A total of 137 patients with 79 different etiologies, aged 2 months to 61 years (mean = 15.48 ± 9.9 years), were enrolled. The mean dosage was 6.45 ± 2.47 mg, and treatment period was 2.0 ± 1.78 years (1.5 months–8 years). Sixty-two patients (44.9%) were treated for >2 years. Ninety-eight patients (71%) were responders, and 93 (67.4%) chose to continue therapy. The mean reduction in seizure frequency was 56.61% ± 34.36%. Sixty patients (43.5%) sustained >75% reduction in seizure frequency, including 38 (27.5%) with >90% reduction in seizure frequency. The following genes showed high treatment efficacy: SCN1A, GNAO1, PIGA, PCDH19, SYNGAP1, POLG1, POLG2, and NEU1. Eleven of 17 (64.7%) patients with Dravet syndrome due to an SCN1A pathogenic variant were responders to perampanel treatment; 35.3% of them had >90% seizure reduction. Other etiologies remarkable for >90% reduction in seizures were GNAO1 and PIGA. Fourteen patients had a continuous spike and wave during sleep electroencephalographic pattern, and in six subjects perampanel reduced epileptiform activity.

Significance

Perampanel demonstrated high safety and efficacy in patients with rare genetic epilepsies, especially in SCN1A, GNAO1, PIGA, PCDH19, SYNGAP1, CDKL5, NEU1, and POLG, suggesting a targeted effect related to glutamate transmission.