Functional brain connectivity indexes derived from low-density EEG of pre-implanted patients as VNS outcome predictors

Objective. In 1/3 of patients, anti-seizure medications may be insufficient, and resective surgery may be offered whenever the seizure onset is localized and situated in a non-eloquent brain region. When surgery is not feasible or fails, vagus nerve stimulation (VNS) therapy can be used as an add-on treatment to reduce seizure frequency and/or severity. However, screening tools or methods for predicting patient response to VNS and avoiding unnecessary implantation are unavailable, and confident biomarkers of clinical efficacy are unclear.Approach. To predict the response of patients to VNS, functional brain connectivity measures in combination with graph measures have been primarily used with respect to imaging techniques such as functional magnetic resonance imaging, but connectivity graph-based analysis based on electrophysiological signals such as electroencephalogram, have been barely explored. Although the study of the influence of VNS on functional connectivity is not new, this work is distinguished by using preimplantation low-density EEG data to analyze discriminative measures between responders and non-responder patients using functional connectivity and graph theory metrics.Main results. By calculating five functional brain connectivity indexes per frequency band upon partial directed coherence and direct transform function connectivity matrices in a population of 37 refractory epilepsy patients, we found significant differences (p< 0.05) between the global efficiency, average clustering coefficient, and modularity of responders and non-responders using the Mann-Whitney U test with Benjamini-Hochberg correction procedure and use of a false discovery rate of 5%.Significance. Our results indicate that these measures may potentially be used as biomarkers to predict responsiveness to VNS therapy.

Fighting Epilepsy with Nanomedicines-Is This the Right Weapon?

Epilepsy is a chronic and complex condition and is one of the most common neurological diseases, affecting about 50 million people worldwide. Pharmacological therapy has been, and is likely to remain, the main treatment approach for this disease. Although a large number of new antiseizure drugs (ASDs) has been introduced into the market in the last few years, many patients suffer from uncontrolled seizures, demanding the development of more effective therapies. Nanomedicines have emerged as a promising approach to deliver drugs to the brain, potentiating their therapeutic index. Moreover, nanomedicine has applied the knowledge of nanoscience, not only in disease treatment but also in prevention and diagnosis. In the current review, the general features and therapeutic management of epilepsy will be addressed, as well as the main barriers to overcome to obtain better antiseizure therapies. Furthermore, the role of nanomedicines as a valuable tool to selectively deliver drugs will be discussed, considering the ability of nanocarriers to deal with the less favourable physical-chemical properties of some ASDs, enhance their brain penetration, reduce the adverse effects, and circumvent the concerning drug resistance.

A phase 2, randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of soticlestat as adjunctive therapy in pediatric patients with Dravet syndrome or Lennox-Gastaut syndrome (ELEKTRA)

OBJECTIVE

Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) are rare treatment-resistant childhood epilepsies classed as developmental and epileptic encephalopathies. ELEKTRA investigated the efficacy and safety of soticlestat (TAK-935) as adjunctive therapy in children with DS or LGS (NCT03650452).

METHODS

ELEKTRA was a phase 2, randomized, double-blind, placebo-controlled study of soticlestat (≤300 mg twice daily, weight-adjusted) in children (aged 2-17 years) with DS, demonstrating three or more convulsive seizures/month, or with LGS, demonstrating four or more drop seizures/month at baseline. The 20-week treatment period comprised an 8-week dose-optimization period and a 12-week maintenance period. Efficacy endpoints included change from baseline in seizure frequency versus placebo. Safety assessments included incidence of treatment-emergent adverse events (TEAEs).

RESULTS

ELEKTRA enrolled 141 participants; 126 (89%) completed the study. The modified intent-to-treat population included 139 participants who received one or more doses of study drug and had one or more efficacy assessments (DS, n = 51; LGS, n = 88). ELEKTRA achieved its primary endpoint: the combined soticlestat-treated population demonstrated a placebo-adjusted median reduction in seizure frequency of 30.21% during the maintenance period (p = .0008, n = 139). During this period, placebo-adjusted median reductions in convulsive and drop seizure frequencies of 50.00% (p = .0002; patients with DS) and 17.08% (p = .1160; patients with LGS), respectively, were observed. TEAE incidences were similar between the soticlestat (80.3%) and placebo (74.3%) groups and were mostly mild or moderate in severity. Serious TEAEs were reported by 15.5% and 18.6% of participants receiving soticlestat and placebo, respectively. TEAEs reported in soticlestat-treated patients with ≥5% difference from placebo were lethargy and constipation. No deaths were reported.

SIGNIFICANCE

Soticlestat treatment resulted in statistically significant, clinically meaningful reductions from baseline in median seizure frequency (combined patient population) and in convulsive seizure frequency (DS cohort). Drop seizure frequency showed a nonstatistically significant numerical reduction in children with LGS. Soticlestat had a safety profile consistent with previous studies.

Treatment with the combination of clavulanic acid and valproic acid led to recovery of neuronal and behavioral deficits in an epilepsy rat model

Epilepsy, which is caused by abnormal neuronal firing in the brain, is a common neurological disease and affects motor and cognitive functions. Excessive levels of glutamate and insufficient levels of inhibitory GABA are involved in its pathophysiology. Valproic acid (Val), a GABAergic agonist, is one of the first-line antiepileptic drugs, but it shows many adverse side effects at the clinical dose. Clavulanic acid (CA), a β-lactamase inhibitor, has been demonstrated to increase glutamate transporter-1 expression. This study evaluated the effects of CA and Val in an epilepsy rat model. Male Wistar rats received intraperitoneal injections of pentylenetetrazol (PTZ, 35 mg/kg, every other day, IP, for 13 days) to induce kindling epilepsy. After four times of PTZ injection, rats received daily treatment with CA (1 or 10 mg/kg, IP), Val (50 or 100 mg/kg, IP), or the combination of CA (1 mg/kg) and Val (50 mg/kg) for 7 consecutive days. Motor, learning, and memory functions were measured. Rats with PTZ-induced kindling exhibited seizures, motor dysfunction, cognitive impairment, and cell loss and reduction of neurogenesis in the hippocampus. Neither 1 mg/kg CA nor 50 mg/kg Val treatment was effective in alleviating behavioral and neuronal deficits. However, treatment with 10 mg/kg CA, 100 mg/kg Val, and the combination of 1 mg/kg CA and 50 mg/kg Val improved these behavioral and neuronal deficits. Particularly, the combination of CA and Val showed synergistic effects on seizure suppression, suggesting the potential for treating epilepsy and related neuronal damage and motor and cognitive deficits.

Liquid chromatographic methods for determination of the new antiepileptic drugs stiripentol, retigabine, rufinamide and perampanel: A comprehensive and critical review

The new antiepileptic drugs perampanel, retigabine, rufinamide and stiripentol have been recently approved for different epilepsy types. Being them an innovation in the antiepileptics armamentarium, a lot of investigations regarding their pharmacological properties are yet to be performed. Besides, considering their broad anticonvulsant activities, an extension of their therapeutic indications may be worthy of investigation, especially regarding other seizure types as well as other central nervous system disorders. Although different liquid chromatographic (LC) methods coupled with ultraviolet, fluorescence, mass or tandem-mass spectrometry detection have already been developed for the determination of perampanel, retigabine, rufinamide and stiripentol, new and more cost-effective methods are yet required. Therefore, this review summarizes the main analytical aspects regarding the liquid chromatographic methods developed for the analysis of perampanel, retigabine (and its main active metabolite), rufinamide and stiripentol in biological samples and pharmaceutical dosage forms. Furthermore, the physicochemical and stability properties of the target compounds will also be addressed. Thus, this review gathers, for the first time, important background information on LC methods that have been developed and applied for the determination of perampanel, retigabine, rufinamide and stiripentol, which should be considered as a starting point if new (bio)analytical techniques are aimed to be implemented for these drugs.

Treatment effects of the combination of ceftriaxone and valproic acid on neuronal and behavioural functions in a rat model of epilepsy

NEW FINDINGS

What is the central question of this study? Imbalance of activities between GABAergic and glutamatergic systems is involved in epilepsy. It is not known whether simultaneously increasing GABAergic and decreasing glutamatergic activity using valproic acid and ceftriaxone, respectively, leads to better seizure control. What is the central question of this study? Ceftriaxone suppressed seizure and cognitive deficits and restored neuronal density and the number of newborn cells in the hippocampus in a rat model of epilepsy. Combined treatment with ceftriaxone and valproic acid showed additive effects in seizure suppression.

ABSTRACT

The pathophysiology of epilepsy is typically considered as an imbalance between inhibitory GABA and excitatory glutamate neurotransmission. Valproic acid (Val), a GABA agonist, is one of the first-line antiepileptic drugs in the treatment of epilepsy, but it exhibits adverse effects. Ceftriaxone (CEF) elevates expression of glutamate transporter-1, enhances the reuptake of synaptic glutamate, increases the number of newborn cells and exhibits neuroprotective effects in animal studies. In this study, we evaluated effects of the combination of CEF and Val on behavioural and neuronal measures in a rat epilepsy model. Male Wistar rats were injected i.p. with pentylenetetrazol (35 mg/kg, every other day for 13 days) to induce the epilepsy model. Ceftriaxone (10 or 50 mg/kg), Val (50 or 100 mg/kg) or the combination of CEF and Val were injected daily after the fourth pentylenetetrazol injection for seven consecutive days. Epileptic rats exhibited seizure and impairments in motor and cognitive functions. Treatment with CEF and Val reduced the seizure and enhanced motor and cognitive functions in a dose-dependent manner. The combination of CEF (10 mg/kg) and Val (50 mg/kg) improved behaviours considerably. Histologically, compared with control animals, epileptic rats exhibited lower neuronal density and a reduction in hippocampal newborn cells but higher apoptosis in the basolateral amygdala, all of which were restored by the treatment with CEF, Val or the combination of CEF and Val. The study findings demonstrated that the combination of low doses of CEF and Val has beneficial effects on seizure suppression, neuroprotection and improvement in motor and cognitive functions in epilepsy.

Modulatory Potential of LncRNA Zfas1 for Inflammation and Neuronal Apoptosis in Temporal Lobe Epilepsy

PURPOSE

This study aimed to elucidate whether lncRNA ZFAS1 is involved in neuronal apoptosis and inflammation in temporal lobe epilepsy (TLE).

MATERIALS AND METHODS

Ninety-six TLE patients were recruited, and their peripheral venous blood was gathered to determine Zfas1 expression with polymerase chain reaction. Neurons were separated from hippocampal tissue of newborn SD rats, and si-Zfas1 or pcDNA3.1-Zfas1 was transfected into the neurons. Inflammatory cytokines released by neurons were determined, and neuronal activities were evaluated through MTT assay, colony formation assay, and flow cytometry.

RESULTS

Serum levels of Zfas1 were higher in TLE patients than in healthy controls (p<0.05). Furthermore, Zfas1 expression in neurons was raised by pcDNA3.1-Zfas1 and declined after silencing of Zfas1 (p<0.05). Transfection of pcDNA-Zfas1 weakened the viability and proliferation of neurons and increased neuronal apoptosis (p<0.05). Meanwhile, pcDNA3.1-Zfas1 transfection promoted lipopolysaccharide-induced release of cytokines, including tumor necrosis factor-α, interleukin (IL)-1, IL-6, and intercellular adhesion molecule-1 (p<0.05), and boosted NF-κB activation by elevating the expression of NF-κB p65, pIκBα, and IKKβ in neurons (p<0.05).

CONCLUSION

Our results indicated that lncRNA ZFAS1 exacerbates epilepsy development by promoting neuronal apoptosis and inflammation, implying ZFAS1 as a promising treatment target for epilepsy.

Perampanel effectiveness and safety as early add-on treatment for focal-onset seizures: PEREAGAL study

BACKGROUND

Perampanel (PER) is an effective adjunctive therapy for controlling focal-onset seizures (FOS), but few studies have examined its effects as an early add-on for the treatment of FOS in daily clinical practice.

METHODS

Our retrospective, multicenter, observational study evaluated the effectiveness and safety of PER as an early add-on in 77 patients with FOS, with and without focal to bilateral tonic-clonic seizures (FBTCS) after 3, 6 and 12 months in a real-world setting.

RESULTS

After 12 months of treatment (median dose 6 [4,8] mg/day), the retention rate was 79.2 % and 60 % of patients (39/65) experienced a ≥50 % reduction in seizure frequency relative to baseline. The seizure-free rate was 38.5 % for all seizures (25/65) and 60 % for FBTCS (12/20). The responder rate at 12 months was significantly higher when PER was given with one concomitant AED (72.2 %) compared to when PER was given with two concomitant AEDs (44.8 %). Drug-related adverse events (AEs) were reported in 40.3 % of patients, most of them being mild (64.2 %). Twelve patients (15.6 %) discontinued treatment because of AEs.

CONCLUSIONS

PER is an effective and safe early add-on for patients with refractory FOS, especially for those with FBTCS.

Models for predicting treatment efficacy of antiepileptic drugs and prognosis of treatment withdrawal in epilepsy patients

Although antiepileptic drugs (AEDs) are the most effective treatment for epilepsy, 30–40% of patients with epilepsy would develop drug-refractory epilepsy. An accurate, preliminary prediction of the efficacy of AEDs has great clinical significance for patient treatment and prognosis. Some studies have developed statistical models and machine-learning algorithms (MLAs) to predict the efficacy of AEDs treatment and the progression of disease after treatment withdrawal, in order to provide assistance for making clinical decisions in the aim of precise, personalized treatment. The field of prediction models with statistical models and MLAs is attracting growing interest and is developing rapidly. What’s more, more and more studies focus on the external validation of the existing model. In this review, we will give a brief overview of recent developments in this discipline.

Development and application of an HPLC-DAD technique for human plasma concentration monitoring of perampanel and lamotrigine in drug-resistant epileptic patients

Perampanel is a third-generation antiepileptic drug (AED), while lamotrigine is a second-generation AED. Both drugs are subject to extensive pharmacokinetic variability between different patients. Furthermore, it has been reported that perampanel and lamotrigine may be implied in pharmacokinetic drug-drug interactions with other AEDs such as carbamazepine or valproate, with consequent alterations of plasma concentrations. This emphasizes the relevance of therapeutic drug monitoring of perampanel and lamotrigine with appropriate bioanalytical methods. Herein, the development and validation of a bioanalytical techique for the simultaneous quantification of perampanel and lamotrigine in human plasma samples is described. The reported method is based on high-performance liquid chromatography coupled with diode-array detection (HPLC-DAD) and sample preparation consists of liquid-liquid extraction. Chromatographic separation of the analytes (lamotrigine and perampanel) and the internal standard (entacapone) was achieved in 12 min on a reversed-phase C₁₈ column at 40 °C by applying a gradient elution program with a mobile phase composed of 0.1% ortho-phosphoric acid pH 2.79 (A) and acetonitrile (B) pumped at 1.0 mL/min. Perampanel was quantified at 320 nm while lamotrigine and the internal standard were monitored at 306 nm. Calibration curves were linear in the concentration range of 0.03-4.5 µg/mL (r² = 0.9978) for perampanel and in the concentration range of 0.25-30 µg/mL (r² = 0.9981) for lamotrigine. Overall precision did not exceed 14.3% and accuracy ranged from -6.08 to 12.66%. Some drugs potentially co-prescribed with perampanel and lamotrigine were tested and did not interfere with the retention times of the analytes and internal standard. The method was then successfully applied for the quantification of perampanel and lamotrigine in plasma samples obtained from 42 drug-resistant epileptic patients admitted to the Coimbra University Hospital Centre (CHUC.EPE, Coimbra, Portugal). In conclusion, it is a suitable method for the therapeutic drug monitoring of lamotrigine and perampanel in drug-resistant epileptic patients, as well as, for the assessment of drug-drug interactions. It can also be adopted by hospitals and laboratories, when HPLC with fluorescence and mass spectrometry detections are unavailable.

Functional connectivity hemispheric contrast (FC-HC): A new metric for language mapping

Development of a task-free method for presurgical mapping of language function is important for use in young or cognitively impaired patients. Resting state connectivity fMRI (RS-fMRI) is a task-free method that may be used to identify cognitive networks. We developed a voxelwise RS-fMRI metric, Functional Connectivity Hemispheric Contrast (FC-HC), to map the language network and determine language laterality through comparison of within-hemispheric language network connections (Integration) to cross-hemispheric connections (Segregation). For the first time, we demonstrated robustness and efficacy of a RS-fMRI metric to map language networks across five groups (total N = 243) that differed in MRI scanning parameters, fMRI scanning protocols, age, and development (typical vs pediatric epilepsy). The resting state FC-HC maps for the healthy pediatric and adult groups showed higher values in the left hemisphere, and had high agreement with standard task language fMRI; in contrast, the epilepsy patient group map was bilateral. FC-HC has strong but not perfect agreement with task fMRI and thus, may reflect related and complementary information about language plasticity and compensation.

Predicting seizure freedom with AED treatment in newly diagnosed patients with MRI-negative epilepsy: A large cohort and multicenter study

OBJECTIVE

We developed and validated a prediction score for predicting the probability of 6-month and 12-month seizure freedom of antiepileptic drug (AED) treatment in newly diagnosed patients with magnetic resonance imaging (MRI)-negative epilepsy.

METHODS

The development cohort included 543 consecutive patients from the Epilepsy Center of Henan Provincial People's Hospital, while the validation cohorts included 493 consecutive patients in two independent cohorts. Univariate analysis and a forward and backward elimination of multivariate Cox regression analysis were used to select predictive factors. The performance of the score was evaluated with C-index, calibration plots, and decision curve analysis. The risk stratification was also performed.

RESULTS

The score included five routinely available predictors including Circadian rhythms, Electroencephalography before AED treatment, Neuropsychiatric disorders, Perinatal brain injury, and History of central nervous system infection (CENPH score). When applied to the external validation cohort, the score showed good discrimination with C-index (development group: 0.83; validation group: 0.78), and calibration plots indicated well calibration, as well as the decision curve analysis showed good predictive accuracy and clinical values in four cohorts. The points of the score were categorized to the following three probability levels for predicting seizure freedom: high probability (0-83.11 points), medium probability (83.11-122.71 points), and low probability (>122.71 points). And online calculator was established to make this score easily applicable in clinical practice.

CONCLUSIONS

We established a simple, practical, and evidence-based prediction score for predicting seizure freedom with AEDs to aid in the clinical consultation and treatment decision for the newly diagnosed patients with MRI-negative epilepsy.

The role of polytherapy in the management of epilepsy: suggestions for rational antiepileptic drug selection

Introduction: Antiepileptic polytherapy may be indicated in patients experiencing drug-resistant epilepsy. To date, there are no evidence-based criteria on how to combine different antiepileptic drugs (AEDs) together, in order to obtain the best therapeutic response.Areas covered: This paper reviews the available data about the various associations of AEDs in patients undergoing polytherapy, focusing on the most effective and well-tolerated polytherapies. Moreover, some controversial aspects of this topic are addressed.Expert opinion: Nowadays, there are no guidelines on polytherapy in patients with epilepsy; thus, the management of pharmacoresistant epilepsy is still uncertain, except for valproate/lamotrigine combination, which seems to be the only one recommended. Data regarding mechanism of action, pharmacokinetics, tolerability, and, more importantly, the analysis of the valuable clinical studies of drug combinations can help physicians to choose the best and most effective AED association for each patient.

Update on Antiepileptic Drugs 2019

PURPOSE OF REVIEW

This article is an update from the article on antiepileptic drug (AED) therapy published in the last Continuum issue on epilepsy and is intended to cover the vast majority of agents currently available to the neurologist in the management of patients with epilepsy. Treatment of epilepsy starts with AED monotherapy. Knowledge of the spectrum of efficacy, clinical pharmacology, and modes of use for individual AEDs is essential for optimal treatment for epilepsy. This article addresses AEDs individually, focusing on key pharmacokinetic characteristics, indications, and modes of use.

RECENT FINDINGS

Since the previous version of this article was published, three new AEDs, brivaracetam, cannabidiol, and stiripentol, have been approved by the US Food and Drug Administration (FDA), and ezogabine was removed from the market because of decreased use as a result of bluish skin pigmentation and concern over potential retinal toxicity.Older AEDs are effective but have tolerability and pharmacokinetic disadvantages. Several newer AEDs have undergone comparative trials demonstrating efficacy equal to and tolerability at least equal to or better than older AEDs as first-line therapy. The list includes lamotrigine, oxcarbazepine, levetiracetam, topiramate, zonisamide, and lacosamide. Pregabalin was found to be less effective than lamotrigine. Lacosamide, pregabalin, and eslicarbazepine have undergone successful trials of conversion to monotherapy. Other newer AEDs with a variety of mechanisms of action are suitable for adjunctive therapy. Most recently, the FDA adopted a policy that a drug's efficacy as adjunctive therapy in adults can be extrapolated to efficacy in monotherapy. In addition, efficacy in adults can be extrapolated for efficacy in children 4 years of age and older. Both extrapolations require data demonstrating that an AED has equivalent pharmacokinetics between its original approved use and its extrapolated use. In addition, the safety of the drug in pediatric patients has to be demonstrated in clinical studies that can be open label. Rational AED combinations should avoid AEDs with unfavorable pharmacokinetic interactions or pharmacodynamic interactions related to mechanism of action.

SUMMARY

Knowledge of AED pharmacokinetics, efficacy, and tolerability profiles facilitates the choice of appropriate AED therapy for patients with epilepsy.

G protein-coupled receptors in acquired epilepsy: Druggability and translatability

As the largest family of membrane proteins in the human genome, G protein-coupled receptors (GPCRs) constitute the targets of more than one-third of all modern medicinal drugs. In the central nervous system (CNS), widely distributed GPCRs in neuronal and nonneuronal cells mediate numerous essential physiological functions via regulating neurotransmission at the synapses. Whereas their abnormalities in expression and activity are involved in various neuropathological processes. CNS conditions thus remain highly represented among the indications of GPCR-targeted agents. Mounting evidence from a large number of animal studies suggests that GPCRs play important roles in the regulation of neuronal excitability associated with epilepsy, a common CNS disease afflicting approximately 1-2% of the population. Surprisingly, none of the US Food and Drug Administration (FDA)-approved (>30) antiepileptic drugs (AEDs) suppresses seizures through acting on GPCRs. This disparity raises concerns about the translatability of these preclinical findings and the druggability of GPCRs for seizure disorders. The currently available AEDs intervene seizures predominantly through targeting ion channels and have considerable limitations, as they often cause unbearable adverse effects, fail to control seizures in over 30% of patients, and merely provide symptomatic relief. Thus, identifying novel molecular targets for epilepsy is highly desired. Herein, we focus on recent progresses in understanding the comprehensive roles of several GPCR families in seizure generation and development of acquired epilepsy. We also dissect current hurdles hindering translational efforts in developing GPCRs as antiepileptic and/or antiepileptogenic targets and discuss the counteracting strategies that might lead to a potential cure for this debilitating CNS condition.

Precursors of seizures due to specific spatial-temporal modifications of evolving large-scale epileptic brain networks

Knowing when, where, and how seizures are initiated in large-scale epileptic brain networks remains a widely unsolved problem. Seizure precursors – changes in brain dynamics predictive of an impending seizure – can now be identified well ahead of clinical manifestations, but either the seizure onset zone or remote brain areas are reported as network nodes from which seizure precursors emerge. We aimed to shed more light on the role of constituents of evolving epileptic networks that recurrently transit into and out of seizures. We constructed such networks from more than 3200 hours of continuous intracranial electroencephalograms recorded in 38 patients with medication refractory epilepsy. We succeeded in singling out predictive edges and predictive nodes. Their particular characteristics, namely edge weight respectively node centrality (a fundamental concept of network theory), from the pre-ictal periods of 78 out of 97 seizures differed significantly from the characteristics seen during inter-ictal periods. The vast majority of predictive nodes were connected by most of the predictive edges, but these nodes never played a central role in the evolving epileptic networks. Interestingly, predictive nodes were entirely associated with brain regions deemed unaffected by the focal epileptic process. We propose a network mechanism for a transition into the pre-seizure state, which puts into perspective the role of the seizure onset zone in this transition and highlights the necessity to reassess current concepts for seizure generation and seizure prevention.

The Outcome of Status Epilepticus and Long-Term Follow-Up

Objective: This study was to investigate the outcome of status epilepticus (SE) associated with antiepileptic therapy during SE and in follow-up period, risk factors including age, co-morbidities, pre-existing epilepsy, and etiology in the East-Hungarian region.

Methods: A prospective cross-sectional database was compiled from outpatient files between 2013 and 2017. Follow-up ended on 30.06.2018.

Results: One hundred and thirty five episodes (male: 68, 50.4%) were evaluated, mean age and follow-up time being 64.1 ± 13.9 years and 39.9 ± 14.2 months, respectively. Of the 89 patients with pre-existing epilepsy, 34 failed to visit the outpatient unit regularly. Case fatality rate was 25.2% and 31 patients (30.7%) died after discharge due to co-morbidities; their mean survival time was 10.44 ± 8 months. Focal, generalized and combined type epilepsies were diagnosed in 67 patients (49.6%), 47 patients (34.8%), and 21 patients (15.6%) of SE, respectively. Nine patients had non-convulsive SE (NCSE). Mean seizure-free period was 6.8 ± 6.9 months. Patients taking carbamazepine (20.9%; OR: 0.37, 95%CI: 0.16–0.82; p = 0.018), levetiracetam (27.5%; OR: 0.51, 95%CI: 0.27–0.97; p = 0.041), or valproate (11.1%; OR: 0.18, 95%CI: 0.05–0.61; p = 0.0043) were expected to achieve seizure freedom after SE. The worst outcome was linked to advanced age, etiology, new onset status epilepticus, NCSE, and focal status epilepsy.

Conclusion: This study highlights the importance of regular care and patient follow-up.

Patterns of antiepileptic drug use in patients with potential refractory epilepsy in Texas Medicaid

OBJECTIVES

Antiepileptic drug (AED) monotherapy is usually effective in 60% of the patients with epilepsy while the remaining patients have refractory epilepsy. This study compared treatment patterns (adherence, persistence, addition, and switching) associated with refractory and nonrefractory epilepsy.

METHODS

Texas Medicaid claims from 09/01/07-12/31/13 were analyzed, and patients eligible for the study 1) were between 18 and 62 years of age, 2) had a prescription claim for an AED during the identification period (03/01/08-12/31/11) with no prior baseline AED use (6-month), and 3) had evidence of epilepsy diagnosis within 6 months of AED use. Based on AED use in the identification period, patients were categorized into "refractory" (≥3AEDs) and "nonrefractory" (<3AEDs) cohorts. The index date was the date of the first AED claim. Patients in both cohorts were matched 1:1 using propensity scoring and compared for adherence (proportion of days covered (PDC) ≥80% vs. <80%), persistence, addition (yes/no), and switching (yes/no) using multivariate conditional regression models. Conditional logistic regression and Cox proportional hazard models were used to address the study objectives.

RESULTS

Of the 10,599 eligible patients, 2798 (26.5%) patients in the refractory cohort were matched to patients in the nonrefractory cohort. Patients in the refractory cohort had significantly higher (p < 0.005) mean (±Standard deviation (SD)) adherence (88.6% (±19.1%) vs. 77.0% ± (25.8%)) and persistence (328.0 (±87.3) days vs. 294.9 ± (113.4) days) as compared with patients in the nonrefractory cohort. Compared with patients with nonrefractory epilepsy, patients with refractory epilepsy were 3.6 times (odds ratio (OR) = 3.553; 95% confidence interval (CI) = 3.060-4.125; p < 0.0001) more likely to adhere to AEDs and had a 34.7% (hazard ratio (HR) = 0.653; 95% CI = 0.608-0.702; p < 0.0001) lower hazard rate of discontinuation of AEDs. Also, patients with refractory epilepsy were 3.7 times (OR = 3.723; 95% CI = 2.902-4.776; p < 0.0001) more likely to add an alternative AED and 3.6 times (OR = 3.591; 95% CI = 3.010-4.284; p < 0.0001) more likely to switch to an alternative AED.

CONCLUSION

Patients with refractory epilepsy were significantly more likely to adhere and persist to AED regimen and were significantly more likely to add and switch to an alternative AED than patients with nonrefractory epilepsy.

Personalized prediction model for seizure-free epilepsy with levetiracetam therapy: a retrospective data analysis using support vector machine

AIMS

To predict the probability of a seizure-free (SF) state in patients with epilepsy (PWEs) after treatment with levetiracetam and to identify the clinical and electroencephalographic (EEG) factors that affect outcomes.

METHODS

Retrospective analysis of PWEs treated with levetiracetam for 3 years identified 22 patients who were SF and 24 who were not. Before starting levetiracetam, 11 clinical factors and four EEG features (sample entropy of α, β, θ, δ) were identified. Overall, 80% of each the two groups were chosen to establish a support vector machine (SVM) model with 5-fold cross-validation, hold-out validation and jack-knife validation. The other 20% were used to predict the efficacy of levetiracetam. The mean impact value (MIV) algorithm was used to rank the relativity between factors and outcomes.

RESULTS

Compared with SF patients, not SF patients displayed a specific decrease in EEG sample entropy in α band from the F4 channel, β band from Fp2 and F8 channels, θ band from C3 channel (P < 0.05). The SVM model based on the clinical and EEG features yielded 72.2% accuracy of 5-fold cross-validation, 75.0% accuracy of jack-knife validation, 67.7% accuracy of hold-out validation in the training set and had a high prediction accuracy of 90% in test set (sensitivity was 100%, area under the receiver operating characteristic curve was 0.96). The feature of β band from Fp2 weighs heavily in the prediction model according to the mean impact value algorithm.

CONCLUSIONS

The efficacy of levetiracetam on newly diagnosed PWEs could be predicted using an SVM model, which could guide antiepileptic drug selection.

Perampanel, an AMPA receptor antagonist: From clinical research to practice in clinical settings

Epileptic seizures are refractory to treatment in approximately one-third of patients despite the recent introduction of many newer antiepileptic drugs (AEDs). Development of novel AEDs therefore remains a high priority. Perampanel is a first-in-class non-competitive selective AMPA receptor antagonist with a unique mechanism of action. Clinical efficacy and safety of perampanel as adjunctive treatment for focal seizures with/without secondary generalization (±SG) and primary generalized tonic-clonic (PGTC) seizures have been established in five phase 3 randomized controlled trials (RCTs), and a long-term extension study, and perampanel is approved as monotherapy for focal seizures ±SG in the USA. In patients with focal seizures ±SG, add-on perampanel resulted in median percent reduction in seizure frequency 23.3%-34.5% and ≥50% responder rate 28.5%-37.6%; in PGTC seizures, these results were 76.5% and 64.2%, respectively. Efficacy among adolescents (reduction in seizure frequency 34.8%-35.6%; ≥50% responder rate 40.9%-45.0%) and elderly people (reduction in seizure frequency 12.5%-16.9%; ≥50% responder rate 22.2%-42.9%) is similar to those in adults, and results remain comparable between Asian (reduction in seizure frequency 17.3%-38.0%) and global populations. Perampanel has been extensively studied in real-world clinical practice, with similar efficacy and safety results to the RCTs (≥50% responder rate 12.8%-75.0%; adverse events of somnolence/sedation, dizziness, ataxia, and behavioral changes). Real-world observational studies suggest that perampanel tolerability can be improved by slow titration (2 mg every 2-4 weeks), and bedtime administration can mitigate somnolence and dizziness. Counseling about the potential for behavioral changes and close monitoring are recommended.

Efficacy and tolerability of adjuvant lacosamide: The role of clinical characteristics and mechanisms of action of concomitant AEDs

OBJECTIVE

The objective of this study was to analyze the effectiveness and long-term tolerability of adjuvant lacosamide (LCM) in a multicenter cohort. We aim to assess outcomes of LCM-containing antiepileptic drug (AED) combinations based upon 'mechanism of action' (MoA) and patient's clinical features.

METHODS

Consecutive patients commenced on LCM, with focal epilepsy were identified from three Australian hospitals. The 12-month efficacy endpoints were greater than 50% reduction in seizure frequency (responders) and seizure freedom. Tolerability endpoints were cessation of LCM for any reason, cessation due to side-effects and censoring due to inefficacy. Outcomes were assessed according to concomitant AEDs according to their MoA and the clinical risk factor profile.

RESULTS

Three hundred ten patients were analyzed and followed for median 17.3months. Two hundred ninety-nine (97%) had drug-resistant epilepsy, and 155 (50%) had tried more than 7 AEDs at LCM commencement. Adjuvant LCM was associated with responder and seizure freedom rate of 29% and 9% respectively at 12months. Lower baseline seizure frequency, a prior 6-month period of seizure freedom at any time since epilepsy diagnosis and being on fewer concomitant AEDs were predictive of 12-month seizure freedom. Previous focal to bilateral tonic-clonic seizures (FBTCS), lower baseline seizure frequency, and concomitant AED reduction after LCM commencement were associated with improved LCM tolerability. No specific MoA AED combinations offered any efficacy or tolerability advantage.

SIGNIFICANCE

Adjuvant LCM is associated with seizure freedom rates of 9% at 12months after commencement and is predicted by lower prior seizure frequency, a period of 6months or longer of seizure freedom since diagnosis and fewer concomitant AEDs. While the broad MoA of concomitant AEDs did not influence efficacy or tolerability outcomes, we have provided a framework that may be utilized in future studies to help identify optimal synergistic AED combinations.

Spotlight on perampanel in the management of seizures: design, development and an update on place in therapy

Purpose

Perampanel is a first-in-class antiepileptic medication approved for the treatment of partial (focal) seizures, and as adjunctive treatment for primarily generalized tonic–clonic seizures. The pharmacology, efficacy data, adverse-effect profile, pharmacokinetics and place in therapy are reviewed.

Summary

Perampanel is indicated for use in patients with epilepsy who are 12 years of age or older. It is the first medication designed specifically to be a non-competitive antagonist at post-synaptic α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors. Efficacy in refractory seizures has been established, and ongoing efficacy demonstrated by post-marketing data. The drug is completely absorbed, and exhibits a half-life that allows for once-daily administration in doses up to 12 mg/day. Drug interactions are minimal, but increased doses may be necessary when given with strong inducers of cytochrome P450 enzymes, including when perampanel is co-administered with other antiepileptics that exhibit this property. The most common adverse effects noted in both clinical trials and post-marketing are dizziness and somnolence. Psychiatric and behavioral adverse events have been documented in both adult and pediatric patients, including those with no corresponding diagnostic history.

Conclusion

Perampanel is a novel adjunctive antiepileptic medication that is an effective option for adolescents and adults with partial seizures, and primarily generalized tonic–clonic seizures uncontrolled with other medications.

EARLY-ESLI study: Long-term experience with eslicarbazepine acetate after first monotherapy failure

PURPOSE

Evaluate real-life experience with eslicarbazepine acetate (ESL) after first monotherapy failure in a large series of patients with focal epilepsy.

METHOD

Multicentre, retrospective, 1-year, observational study in patients older than 18 years, with focal epilepsy, who had failed first antiepileptic drug monotherapy and who received ESL. Data from clinical records were analysed at baseline, 3, 6 and 12 months to assess effectiveness and tolerability.

RESULTS

Eslicarbazepine acetate was initiated in 253 patients. The 1-year retention rate was 92.9%, and the final median dose of ESL was 800 mg. At 12 months, 62.3% of patients had been seizure free for 6 months; 37.3% had been seizure free for 1 year. During follow-up, 31.6% of the patients reported ESL-related adverse events (AEs), most commonly somnolence (8.7%) and dizziness (5.1%), and 3.6% discontinued due to AEs. Hyponatraemia was observed in seven patients (2.8%). After starting ESL, 137 patients (54.2%) withdrew the prior monotherapy and converted to ESL monotherapy; 75.9% were seizure free, 87.6% were responders, 4.4% worsened, and 23.4% reported ESL-related AEs.

CONCLUSION

Use of ESL after first monotherapy failure was associated with an optimal seizure control and tolerability profile. Over half of patients were converted to ESL monotherapy during follow-up.

Alterations in Spontaneous Brain Activity and Functional Network Reorganization following Surgery in Children with Medically Refractory Epilepsy: A Resting-State Functional Magnetic Resonance Imaging Study

For some patients with medically refractory epilepsy (MRE), surgery is a safe and effective treatment for controlling epilepsy. However, the functional consequences of such surgery on brain activity and connectivity in children remain unknown. In the present study, we carried out a longitudinal study using resting-state functional magnetic resonance imaging in 10 children with MRE before and again at a mean of 79 days after surgery, as well as in a group of 28 healthy controls. Compared with the controls, children with epilepsy exhibited abnormalities in intrinsic activity in the thalamus, putamen, pallidum, insula, hippocampus, cerebellum, and cingulate gyrus both before and after surgery. Longitudinal analyses showed that the amplitude of low frequency fluctuations (ALFF) increased in the parietal–frontal cortex and decreased in the deep nuclei from pre- to post-surgery. The percentage changes in ALFF values in the deep nuclei were positively correlated with the age of epilepsy onset. Functional connectivity (FC) analyses demonstrated a reorganization of FC architecture after surgery. These changes in brain activity and FC after surgery might indicate that the previously disrupted functional interactions were reorganized after surgery. All these results provide preliminary evidence that the age of epilepsy onset may have some potential to predict the outcome of brain functional reorganization after surgery in children with MRE.

The association of SCN1A p.Thr1067Ala polymorphism with epilepsy risk and the response to antiepileptic drugs in Slovenian children and adolescents with epilepsy

PURPOSE

The voltage-gated sodium channel SCN1A mutations are involved in epileptogenesis and may be associated with different epilepsy phenotypes. The SCN1A channel is also an important antiepileptic drug (AED) target. The aim of this study was to investigate if the SCN1A c.3184A>G/p.Thr1067Ala polymorphism modifies the epilepsy risk or is associated with the responsiveness to AEDs in Slovenian children and adolescents with epilepsy.

METHODS

In total, 216 paediatric patients with epilepsy were consecutively recruited during routine outpatient follow-up visits between January 2011 and December 2014. All patients and 95 healthy controls, all Central European Caucasians, were genotyped for the SCN1A c.3184A>G/p.Thr1067Ala polymorphism. Clinical data on all patients were collected retrospectively. The response to AEDs was classified as seizure remission (a minimum of one year of seizure freedom before inclusion) or no remission. Univariate and multivariate logistic regression was used to determine the association of genotypes with binary outcomes.

RESULTS

114 patients (52.8%) had achieved remission, while 102 (47.2%) had failed to do so. Carriers of at least one polymorphic SCN1A c.3184A>G/p.Thr1067Ala G allele tended to have a lower epilepsy risk (OR=0.38, 95% CI=0.18-0.79, P=0.010) and were significantly more likely to achieve remission (OR=2.00, 95% CI=1.16-3.46, P=0.013). Girls were less likely to achieve remission (P=0.055). Patients in remission tended to be older at first seizure in comparison to the group failing to achieve remission (OR=1.06, 95% CI=0.99-1.14, P=0.099), but this association did not reach statistical significance.

CONCLUSION

The polymorphic SCN1A c.3184A>G/p.Thr1067Ala G allele was associated with a lower risk of epilepsy and a higher remission rate in Slovenian children and adolescents with epilepsy.

Novel construction of diversely functionalized N-heteroaryl-2-pyridones via copper(ii)-catalyzed [3+2+1] annulation

A facile synthesis of diversely functionalized N-heteroaryl-2-pyridones is achieved by Cu(OTf)₂-catalyzed [3+2+1] annulation of various 2-aminopyridines via cascade reaction.

Pyridoxine-dependent convulsions among children with refractory seizures: A 3-year follow-up study

Introduction:

Epilepsy accounts for 1% of the global disease burden and about 8–10 million epilepsy patients live in India. About 30–40% of these patients become drug-resistant and land up with palliative or disease-modifying surgeries. This is a situation causing great concern in view of the psychosocial and economic burden on the patient and the family apart from severe cognitive and motor consequences, especially in children. Therefore, it is mandatory to have an insight into the wide spectrum of causes with reference to refractoriness to antiepileptic medications in children with epilepsy.

Patients and Methods:

Children admitted under our team with refractory epilepsy as per the International League Against Epilepsy (ILAE) criteria in the last 3 years were included in the study.

Results:

Refractory epilepsy constituted 13.3% of inpatients in the pediatric group. Males dominated with 68.9% of these patients. Nearly 34.4% of these patients were found to suffer from various neurometabolic diseases. Almost 3.5% were due to pyridoxine-dependent convulsions. This group of patients showed an excellent response to dietary manipulation, disease-modifying treatment for the metabolic disorder, and supportive small-dose anticonvulsants. During follow-up, they showed very good response with reference to global development and seizure control.

Conclusion:

Pyridoxine-dependent convulsions are relatively rare forming about 3.5% of refractory epilepsies in this series. With initiation of appropriate therapy, results with reference to seizure control as well as neurodevelopment became evident within 2 weeks, and at 1-year follow-up, complete independence for majority of the needed activities is achieved with minimum cost, almost zero side effects, and absolute elimination of the need for palliative surgery.

Sleep quality and daytime sleepiness in patients treated with adjunctive perampanel for focal seizures

PURPOSE

The purpose of this study was to evaluate subjective sleep quality and daytime sleepiness in patients receiving adjunctive perampanel for focal seizures.

METHODS

We conducted a multicenter, prospective, interventional, open-label study in patients aged >16 with focal seizures who received adjunctive perampanel (flexible dosing: 2-12mg). Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness with the Epworth Sleepiness Scale (ESS) at baseline and 3 and 6months after initiating perampanel. Patients with modifications in their baseline AEDs or sleep medications were excluded.

RESULTS

In 72 patients with drug-resistant focal seizures, mean baseline PSQI score (±standard deviation) was 7.26 (±4.6), and ESS was 6.19 (±4.2). At 3months (median perampanel dose: 4mg), there was no significant mean change from baseline in ESS score (n=61) and a significant improvement in PSQI (-1.51 points; n=44; p=0.007), driven mainly by improved sleep efficiency (p=0.012). In the 31 patients with 6-month data, ESS (but not PSQI) improved significantly at 6months vs baseline (p=0.029). The only factor significantly correlated with sleep parameters was number of baseline AEDs (higher number correlated with worse daytime sleepiness). Seizure frequency was reduced significantly from baseline at 3 and 6months. In bivariate analysis, neither PSQI nor ESS was associated with seizure frequency, suggesting that the changes in daytime sleepiness and sleep quality may be independent of the direct effect on seizures.

CONCLUSION

Adjunctive perampanel did not worsen sleep quality or daytime sleepiness at 3months and reduced daytime sleepiness in patients continuing perampanel for 6months. Perampanel may be a suitable AED in patients with sleep disorders, in addition to refractory focal seizures.

Perampanel: A Review in Drug-Resistant Epilepsy

Perampanel (Fycompa®), an orally-active, selective, noncompetitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist, is a first-in-class antiepileptic drug (AED) offering the convenience of once-daily administration. In the EU and US, perampanel is approved in patients with epilepsy aged ≥12 years for the adjunctive treatment of primary generalized tonic-clonic seizures (GTCS) and partial-onset seizures (POS; with or without secondary generalization). In phase III trials of 17 or 19 weeks' duration, add-on perampanel ≤12 mg/day significantly improved seizure control in patients aged ≥12 years who were experiencing either primary GTCS or POS (with or without secondary generalization), despite ongoing treatment with stable dosages of one to three AEDs. Improvements in seizure control were maintained for up to 2 years in extensions of these core studies. Perampanel also provided sustained seizure control for up to ≈4 years in an extension of two phase II studies in patients aged ≥18 years with drug-resistant POS. Adjunctive perampanel therapy was generally well tolerated. Treatment-emergent adverse events were most commonly CNS-related (e.g. dizziness, somnolence, fatigue and irritability) and dose-related; however, most were of mild to moderate intensity. Clinical experience with perampanel is accumulating, although comparative studies and pharmacoeconomic data that could assist in positioning it relative to other AEDS that are approved and/or recommended as adjunctive therapy are lacking. Nonetheless, on the basis of its overall clinical profile and unique mechanism of action, perampanel is a useful additional adjunctive treatment option for patients with drug-resistant POS, with or without secondary generalization, and primary GTCS.

EPICON consensus: recommendations for proper management of switching to eslicarbazepine acetate in epilepsy

INTRODUCTION

The objective of the EPICON Project is to develop a set of recommendations on how to adequately switch from carbamazepine (CBZ) and oxcarbazepine (OXC) to eslicarbazepine acetate (ESL) in some patients with epilepsy.

METHODS

A steering committee drafted a questionnaire of 56 questions regarding the transition from CBZ or OXC to ESL in clinical practice (methodology and change situation). The questionnaire was then distributed to 54 epilepsy experts in 2 rounds using the Delphi method. An agreement/disagreement consensus was defined when a median ≥ 7 points or ≤ 3 was achieved, respectively, and a relative interquartile range ≤ 0.40. We analysed the results obtained to reach our conclusions.

RESULTS

Our main recommendations were the following: switching from CBZ to ESL must be carried out over a period of 1 to 3 weeks with a CBZ:ESL dose ratio of 1:1.3 and is recommended for patients who frequently forget to take their medication, those who work rotating shifts, polymedicated patients, subjects with cognitive problems, severe osteoporosis-osteopaenia, dyslipidaemia, or liver disease other than acute liver failure, as well as for men with erectile dysfunction caused by CBZ. The transition from OXC to ESL can take place overnight with an OXC:ESL dose ratio of 1:1 and it is recommended for patients who frequently forget to take their medication, those who work rotating shifts, polymedicated patients, or those with cognitive problems. The transition was not recommended for patients with prior rash due to CBZ or OXC use.

CONCLUSION

The EPICON Project offers a set of recommendations about the clinical management of switching from CBZ or OXC to ESL, using the Delphi method.

Efficacy and safety of brivaracetam for partial-onset seizures in 3 pooled clinical studies

Objective:

To assess the efficacy, safety, and tolerability of adjunctive brivaracetam (BRV), a selective, high-affinity ligand for SV2A, for treatment of partial-onset (focal) seizures (POS) in adults.

Methods:

Data were pooled from patients (aged 16–80 years) with POS uncontrolled by 1 to 2 antiepileptic drugs receiving BRV 50, 100, or 200 mg/d or placebo, without titration, in 3 phase III studies of BRV (NCT00490035, NCT00464269, and NCT01261325, ClinicalTrials.gov, funded by UCB Pharma). The studies had an 8-week baseline and a 12-week treatment period. Patients receiving concomitant levetiracetam were excluded from the efficacy pool.

Results:

In the efficacy population (n = 1,160), reduction over placebo (95% confidence interval) in baseline-adjusted POS frequency/28 days was 19.5% (8.0%–29.6%) for 50 mg/d (p = 0.0015), 24.4% (16.8%–31.2%) for 100 mg/d (p < 0.00001), and 24.0% (15.3%–31.8%) for 200 mg/d (p < 0.00001). The ≥50% responder rate was 34.2% (50 mg/d, p = 0.0015), 39.5% (100 mg/d, p < 0.00001), and 37.8% (200 mg/d, p = 0.00003) vs 20.3% for placebo (p < 0.01). Across the safety population groups (n = 1,262), 90.0% to 93.9% completed the studies. Treatment-emergent adverse events (TEAEs) were reported by 68.0% BRV overall (n = 803) and 62.1% placebo (n = 459). Serious TEAEs were reported by 3.0% (BRV) and 2.8% (placebo); 3 patients receiving BRV and one patient receiving placebo died. TEAEs in ≥5% patients taking BRV (vs placebo) were somnolence (15.2% vs 8.5%), dizziness (11.2% vs 7.2%), headache (9.6% vs 10.2%), and fatigue (8.7% vs 3.7%).

Conclusions:

Adjunctive BRV was effective and generally well tolerated in adults with POS.

Classification of evidence:

This analysis provides Class I evidence that adjunctive BRV is effective in reducing POS frequency in adults with epilepsy and uncontrolled seizures.

Predictability of uncontrollable multifocal seizures - towards new treatment options

Drug-resistant, multifocal, non-resectable epilepsies are among the most difficult epileptic disorders to manage. An approach to control previously uncontrollable seizures in epilepsy patients would consist of identifying seizure precursors in critical brain areas combined with delivering a counteracting influence to prevent seizure generation. Predictability of seizures with acceptable levels of sensitivity and specificity, even in an ambulatory setting, has been repeatedly shown, however, in patients with a single seizure focus only. We did a study to assess feasibility of state-of-the-art, electroencephalogram-based seizure-prediction techniques in patients with uncontrollable multifocal seizures. We obtained significant predictive information about upcoming seizures in more than two thirds of patients. Unexpectedly, the emergence of seizure precursors was confined to non-affected brain areas. Our findings clearly indicate that epileptic networks, spanning lobes and hemispheres, underlie generation of seizures. Our proof-of-concept study is an important milestone towards new therapeutic strategies based on seizure-prediction techniques for clinical practice.

Towards precision medicine in epilepsy surgery

Up to a third of all patients with epilepsy are refractory to medical therapy even in the context of the introduction of new antiepileptic drugs (AEDs) with considerable advantages in safety and tolerability over the last two decades. It has been widely accepted that epilepsy surgery is a highly effective therapeutic option in a selected subset of patients with refractory focal seizure. There is no doubt that accurate localization of the epileptogenic zone (EZ) is crucial to the success of resection surgery for intractable epilepsy. The pre-surgical evaluation requires a multimodality approach wherein each modality provides unique and complimentary information. Accurate localization of EZ still remains challenging, especially in patients with normal features on MRI. Whereas substantial progress has been made in the methods of pre-surgical assessment in recent years, which widened the applicability of surgical treatment for children and adults with refractory seizure. Advances in neuroimaging including voxel-based morphometric MRI analysis, multimodality techniques and computer-aided subtraction ictal SPECT co-registered to MRI have improved our ability to identify subtle structural and metabolic lesions causing focal seizure. Considerable observations from animal model with epilepsy and pre-surgical patients have consistently found a strong correlation between high frequency oscillations (HFOs) and epileptogenic brain tissue that suggest HFOs could be a potential biomarker of EZ. Since SEEG emphasizes the importance to study the spatiotemporal dynamics of seizure discharges, accounting for the dynamic, multidirectional spatiotemporal organization of the ictal discharges, it has greatly deep our understanding of the anatomo-electro-clinical profile of seizure. In this review, we focus on some state-of-the-art pre-surgical investigations that contribute to the precision medicine. Furthermore, advances also provide opportunity to achieve the minimal side effects and maximal benefit individually, which meets the need for the current concept of precision medicine in epilepsy surgery.

[Algorithms of mono- and polytherapy in clinical epileptology]

The large number of antiepileptic drugs (AEDs) at the physician's disposal provides not only a broad therapeutic potential in the treatment of epilepsy (EP), but creates difficulties in the adequate choice of AED. The sufficient experience in the management of patients with epilepsy has been gained so far in the world, based on which the International League Against Epilepsy (ILAE), updated classification, adopted the basic definition of efficiency, remission, resistance, evidence of research on the effectiveness of AED therapy, and introduced the concept of "resolved" epilepsy. In this article, a group of Russian experts suggest recommendations on the main steps in the choice of therapy in epilepsy. Possible drug interactions between different AEDs and other drugs as well as main characteristics of mono- and polytherapy of epilepsy are described. Some features of the use of AEDs in the elderly, characteristics of the "female" epilepsy related to the reproductive function and basic requirements for the therapy of epilepsy in children are presented.

Perspectives on treatment options for mesial temporal lobe epilepsy with hippocampal sclerosis

INTRODUCTION

Mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) is a syndrome that is often refractory to drug treatment. The effects on specific syndromes are not currently available from the pre-marketing clinical development of new AEDs; this does not allow the prediction of whether new drugs will be more effective in the treatment of some patients.

AREAS COVERED

We have reviewed all the existing literature relevant to the understanding of a potential effectiveness in MTLE-HS patients for the latest AEDs, namely brivaracetam, eslicarbazepine, lacosamide, perampanel and retigabine also including the most relevant clinical data and a brief description of their pharmacological profile. Records were identified using predefined search criteria using electronic databases (e.g., PubMed, Cochrane Library Database of Systematic Reviews). Primary peer-reviewed articles published up to the 15 June 2015 were included.

EXPERT OPINION

All the drugs considered have the potential to be effective in the treatment of MTLE-HS; in fact, they possess proven efficacy in animal models; currently considered valuable tools for predicting drug efficacy in TLE. Furthermore, for some of these (e.g., lacosamide and eslicarbazepine) data are already available from post-marketing studies while brivaracetam acting on SV2A like levetiracetam might have the same potential effectiveness with the possibility to be more efficacious considering its ability to inhibit voltage gated sodium channels; finally, perampanel and retigabine are very effective drugs in animal models of TLE.

Management of epilepsy in patients with Rett syndrome: perspectives and considerations

Rett syndrome (RTT) is a common neurodevelopmental disorder that appears in infancy with regression of acquired motor skills, loss of purposeful activity, hand stereotypies, loss of acquired spoken language, and seizures. Epilepsy affects the majority of patients in a specific clinical stage of the disease and is drug resistant in approximately one-third of cases. The association of epilepsy and even drug-resistant epilepsy has been reported in certain genotypes of the methyl-CpG-binding protein 2 mutation, which is present in a majority of patients with classical RTT. The evolution of electroencephalographic abnormalities accompanying the clinical development of the syndrome is well described, but much less is known about the seizure semiology and the effectiveness of specific antiepileptic drugs. The aim of this review is to present the clinical and electrophysiological aspects of epilepsy in RTT and the current treatment approach.

Adjunctive brivaracetam for patients with refractory partial seizures: A meta-analysis of randomized placebo-controlled trials

OBJECTIVE

To evaluate the clinical efficacy and safety of the newer antiepileptic drug (AED), brivaracetam (BRV), as adjunctive therapy for adults with refractory partial seizures.

METHODS

Randomized-controlled trials (RCTs) of BRV in the treatment of refractory partial seizure were systematically reviewed and quantified using fixed- or random-effects meta-analysis. 50% responder rate, seizure free rate and adverse events in the treatment period were analyzed as outcomes for measuring efficacy and safety. Pooled effects of risk ratio (RR) and 95% confidence interval (CI) were derived from meta-analysis implemented in RevMan 5.2.

RESULTS

Five RCTs were identified for inclusion, and included a total of 1639 patients. The pooled RR of BRV vs. placebo as adjunctive therapy for adults with refractory partial seizure was 1.80 (95% CI 1.43-2.26, P < 0.00001) for 50% responder rates, 4.11 (95% CI 1.39-12.21, P = 0.01) for seizure free rates, 1.08 (95% CI 0.73-1.59; P = 0.70) for withdrawal rates. There was no evidence of a statistically significant association between the use of BRV and most adverse events, except somnolence (RR 1.63, 95% CI 1.08-2.45, P = 0.02) and fatigue (RR 2.05, 95% CI 1.19-3.53, P = 0.009).

CONCLUSION

This study confirmed significant effects of BRV as adjunctive treatment of refractory partial seizures. This study also demonstrated the good tolerability profile of adjunctive BRV for patients with epilepsy. Further large clinical and pharmacovigilance studies are needed to investigate the long-term efficacy and safety of BRV and, furthermore, to suggest an optimal BRV dosage for clinical use.

Drug-resistant epilepsy: definition and treatment alternatives

INTRODUCTION

Drug-resistant epilepsy affects 25% of all epileptic patients, and quality of life decreases in these patients due to their seizures. Early detection is crucial in order to establish potential treatment alternatives and determine if the patient is a surgical candidate.

DEVELOPMENT

PubMed search for articles, recommendations published by major medical societies, and clinical practice guidelines for drug-resistant epilepsy and its medical and surgical treatment options. Evidence and recommendations are classified according to the criteria of the Oxford Centre for Evidence-Based Medicine (2001) and the European Federation of Neurological Societies (2004) for therapeutic actions.

CONCLUSIONS

Identifying patients with drug-resistant epilepsy is important for optimising drug therapy. Experts recommend rational polytherapy with antiepileptic drugs to find more effective combinations with fewer adverse effects. When adequate seizure control is not achieved, a presurgical evaluation in an epilepsy referral centre is recommended. These evaluations explore how to resect the epileptogenic zone without causing functional deficits in cases in which this is feasible. If resective surgery is not achievable, palliative surgery or neurostimulation systems (including vagus nerve, trigeminal nerve, or deep brain stimulation) may be an option. Other treatment alternatives such as ketogenic diet may also be considered in selected patients.