Lacosamide: a new approach to target voltage-gated sodium currents in epileptic disorders

Lacosamide as an Adjunctive Therapy in the Management of Refractory Neonatal Seizures: A Retrospective Study

ObjectiveNeonatal seizures present significant treatment challenges, often requiring adjunctive antiseizure medications. This study aimed to evaluate the efficacy of lacosamide as an adjunctive antiseizure medication in managing refractory neonatal seizures.MethodsThe study included neonates up to 44 weeks of corrected gestational age who received lacosamide treatment at a level 4 neonatal intensive care unit between January 2015 and December 2023. The collected data encompassed demographic features, birth history, perinatal/postnatal complications, seizure characteristics, and treatment details. The primary outcome was the response to lacosamide, assessed by changes in total seizure burden on electroencephalography (EEG). The cohort characteristics were compared between nonresponders and responders.ResultsThe final analysis was conducted on 18 neonates with available EEG data. Of all patients, 72% showed a favorable response to lacosamide treatment, as evidenced by a reduced seizure burden on EEG. The demographic and clinical characteristics of the neonates varied, including a range of seizure etiologies. Responder and nonresponder groups had no differences in clinical characteristics.ConclusionThis study suggests that lacosamide may be an effective adjunctive antiseizure medication in treating refractory neonatal seizures. Further prospective studies are warranted to confirm these findings and explore the long-term outcomes and safety profile of lacosamide in this vulnerable patient group.

Neuroprotective potential of topiramate, pregabalin and lacosamide combination in a rat model of acute SE and intractable epilepsy: Perspectives from electroencephalographic, neurobehavioral and regional degenerative analysis

The lithium-pilocarpine model is commonly used to recapitulate characteristics of human intractable focal epilepsy. In the current study, we explored the impact of topiramate (TPM) alone and in combination with pregabalin and lacosamide administration for 6 weeks on the evolution of spontaneous recurrent seizures (SRS) and disease-modifying potential on associated neuropsychiatric comorbidities. In addition, redox impairments and neurodegeneration in hippocampus regions vulnerable to temporal lobe epilepsy (TLE) were assessed by cresyl violet staining. Results revealed that acute electrophysiological (EEG) profiling of the ASD cocktail markedly halted sharp ictogenic spikes as well as altered dynamics of brain wave oscillations thus validating the need for polytherapy vs. monotherapy. In TLE animals, pharmacological intervention for 6 weeks with topiramate 10 mg/kg in combination with PREG and LAC at the dose of 20 mg/kg exhibited marked protection from SRS incidence, improved body weight, offensive aggression, anxiety-like behavior, cognitive impairments, and depressive-like behavior (p < 0.05). Moreover, combination therapy impeded redox impairments as evidenced by decreased MDA and AchE levels and increased activity of antioxidant SOD, GSH enzymes. Furthermore, polytherapy rescued animals from SE-induced neurodegeneration with increased neuronal density in CA1, CA3c, CA3ab, hilus, and granular cell layer (GCL) of the dentate gyrus. In conclusion, early polytherapy with topiramate in combination with pregabalin and lacosamide prompted synergy and prevented epileptogenesis with associated psychological and neuropathologic alterations.

Unique electrophysiological property of a novel Nav1.7, Nav1.8, and Nav1.9 sodium channel blocker, ANP-230

Voltage-gated sodium channel subtypes, Nav1.7, Nav1.8, and Nav1.9 are predominantly expressed in peripheral sensory neurons. Recent genetic studies have revealed that they are involved in pathological pain processing and that the blockade of Nav1.7, Nav1.8, or Nav1.9 will become a promising pharmacotherapy especially for neuropathic pain. A growing number of drug discovery programs have targeted either of the subtypes to obtain a selective inhibitor which can provide pain relief without affecting the cardiovascular and central nervous systems, though none of them has been approved yet. Here we describe the in vitro characteristics of ANP-230, a novel sodium channel blocker under clinical development. Surprisingly, ANP-230 was shown to block three pain-related subtypes, human Nav1.7, Nav1.8, and Nav1.9 with similar potency, but had only low inhibitory activity to human cardiac Nav1.5 channel and rat central Nav channels. The voltage clamp experiments using different step pulse protocols revealed that ANP-230 had a "tonic block" mode of action without state- and use-dependency. In addition, ANP-230 caused a depolarizing shift of the activation curve and decelerated gating kinetics in human Nav1.7-stably expressing cells. The depolarizing shift of activation curve was commonly observed in human Nav1.8-stably expressing cells as well as rat dorsal root ganglion neurons. These data suggested a quite unique mechanism of Nav channel inhibition by ANP-230. Finally, ANP-230 reduced excitability of rat dorsal root ganglion neurons in a concentration dependent manner. Collectively, these promising results indicate that ANP-230 could be a potent drug for neuropathic pain.

Presynaptic antiseizure medications - basic mechanisms and clues for their rational combinations

Among clinically highly efficient antiseizure medications (ASMs) there are modifiers of the presynaptic release machinery. Of them, levetiracetam and brivaracetam show a high affinity to the synaptic vesicle protein type 2 A (SV2A), whereas pregabalin and gabapentin are selective ligands for the α2δ1 subunits of the voltage-gated calcium channels. In this paper, we present recent progress in understanding the significance of presynaptic release machinery in the neurochemical mechanisms of epilepsy and ASMs. Furthermore, we discuss whether the knowledge of the basic mechanisms of the presynaptically acting ASMs might help establish a rational polytherapy for drug-resistant epilepsy.

Cardiac adverse events associated with lacosamide: a disproportionality analysis of the FAERS database

Lacosamide was the first approved third-generation antiepileptic drug. However, real-world data regarding its adverse cardiac reactions in large samples still need to be completed. We evaluated the cardiac safety profile of lacosamide using the Food and Drug Administration Adverse Event Reporting System (FAERS). We performed disproportionality analysis computing reporting odds ratio (ROR) as a quantitative metric to assess the signal of lacosamide-related cardiac adverse events (AEs) from 2013 Q1 to 2022 Q4. The signal was considered significant when the lower limit of the 95% confidence interval (CI) of the ROR exceeded 1, and ≥ 5 AEs were reported. Serious and nonserious cases were compared by statistical analysis, and signals were further prioritized using a rating scale. A total of 812 cardiac AEs associated with lacosamide were identified, and 92 signals were detected, of which 17 AEs were significantly associated signals. The median time-to-onset (TTO) for moderate priority signals was 10 days, whereas for weak priority signals, it was 54 days. Notably, all cardiac AEs exhibited an early failing pattern, indicating the risk gradually decreasing. Based on the comprehensive analysis of the FAERS database and prioritization of cardiac AE signals, our research enhances the awareness among healthcare professionals regarding cardiac AEs associated with lacosamide.

Case report: Gait-induced palilalia in a patient with hemiplegia due to cerebral infarction

Background

Palilalia is a type of speech characterized by compulsive repetition of words, phrases, or syllables. Several reports have noted that palilalia can occur in response to external verbal stimuli. Here, we report, for the first time, a patient with palilalia induced by gait, which we call "movement-related palilalia."

Case presentation

Eleven months after the onset of cerebral infarction sparing the right precentral gyrus and its adjacent subcortical regions, a 63-year-old, left-handed Japanese man was referred for psychiatric consultation because of a complaint of irritability caused by the stress of compulsive repetition of a single meaningless word, "wai." The repetition of a word, palilalia, in this case, was characterized by its predominant occurrence during walking and by its melodic tones. The palilalia during walking disappeared almost completely after 5 months of treatment with carbamazepine 600 mg.

Conclusion

Palilalia induced by gait can occur in patients with a history of cerebral infarction. This palilalia during walking may be due to the reorganization of networks in areas nearby or surrounding cerebral infarcts.

Clinical Analysis of Lacosamide Monotherapy in the Treatment of Self-Limited Epilepsy with Centrotemporal Spikes

Objective

To evaluate the efficacy and safety of lacosamide (LCM) monotherapy in the treatment of self-limited epilepsy with centrotemporal spikes (SeLECTS).

Methods

In this study, 89 children with SeLECTS who were treated with LCM monotherapy in the Children's Hospital Affiliated to Soochow University from June 2019 to June 2021 were included. Clinical seizures and spike wave index (SWI) on video EEG during slow-wave sleep were evaluated before and after treatment. The role of LCM monotherapy in improving SWI, controlling clinical seizures and improving cognition was analyzed, and corresponding adverse reactions were documented.

Results

There were 52 males and 37 females in this group, with an average age of 7.6 ± 2.1 years. The total effective rate was 93.83% and at 18 months of treatment, the cumulative control rate was 85.19%, the retention rate was 91.01% and the effective rate in terms of EEG spike index was 72.92%, all of which showed a high rate; there was no statistically significant difference in intelligence quotient before and after treatment (P > 0.05). In addition, it was found in the study that the earlier the age of onset, the less obvious the improvement in SWI after LCM treatment; the lower the baseline seizure frequency, the more significant the improvement in SWI after LCM treatment.

Conclusion

LCM monotherapy had curative effect and adverse reactions for SeLECTS, with no negative impact on cognition. These significant findings indicate that LCM is likely to become a widely prescribed ASM for the treatment of SeLECTS. Meanwhile, the onset age and baseline seizure frequency had certain value in judging prognosis and predicting curative effect.

Antiseizure Medication-Induced Nystagmus During Eye Closure Identified by Electroencephalography

Nystagmus is a well-known side effect of antiseizure medicines (ASMs), but it is often underestimated and overlooked. Here, we describe a case in which nystagmus during eye closure was identified early using routine electroencephalography (EEG). A 34-year-old man developed focal epilepsy after head trauma at the age of 25 years. The patient was treated with carbamazepine but liver dysfunction was observed; therefore, treatment was attempted with lacosamide (LCM) and lamotrigine. With an increase in the LCM dose, steep potential changes suggestive of horizontal nystagmus were observed in the electrooculogram, F7, and F8 on EEG, and the patient complained of eye shaking during eye closure. These symptoms and EEG findings improved with LCM dose reduction. If the presence of nystagmus is identified on EEG coincidentally and a patient's subjective symptoms with ASM are confirmed, it is advisable to taper and/or discontinue the causative agent.

Research Status, Synthesis and Clinical Application of Antiepileptic Drugs

According to the 2017 ILAE's official definition, epilepsy is a slow brain disease state characterized by recurrent episodes. Due to information released by ILAE in 2017, it can be divided into four types, including focal epilepsy, generalized epilepsy, combined generalized, and focal epilepsy, and unknown epilepsy. Since 1989, 24 new antiepileptic drugs have been approved to treat different types of epilepsy. Besides, there are a variety of antiepileptic medications under clinical monitoring. These novel antiepileptic drugs have plenty of advantages. Over the past 33 years, there have been many antiepileptic drugs on the mearket, but no one has been found that can completely cure epilepsy. In this paper, the mentioned drugs were classified according to their targets, and the essential information, and clinical studies of each drug were described. The structure-activity relationship of different chemical structures was summarized. This paper provides help for the follow-up research on epilepsy drugs.

Real-world experience with cenobamate: A systematic review and meta-analysis

PURPOSE

Despite many new ASM, the rate of patients with drug-resistant epilepsy (DRE) has not changed. Cenobamate (CNB) is a novel ASM for the treatment of focal-onset seizures in adults with high seizure freedom rates in randomized controlled trials (RCT). Although CNB appears to be effective, it is not commonly prescribed to patients with DRE, resulting in a lack of "real-world data".

METHODS

To evaluate the real-world effect of CNB and to assess the generalizability of RCT data, a systematic review and meta-analysis was conducted. Pooled proportions were calculated using a random intercept logistic regression model.

RESULTS

The analysis included seven studies with a total of 229 patients with DRE, 77.3 % of whom were adults and 91.5 % had focal-onset seizures. Seizure reduction >50 % was achieved in 68 % of patients [54.54; 79.07], with seizure freedom in 16.2 % [8.38; 28.97]. There was no difference between pediatric and adult patients. CNB was discontinued in 10 % [6.74; 14.6] of patients, mostly due to lack of efficacy (39 %) or adverse effects (AE, 43 %). AE, observed in 57.3 % [39.7; 73.2] of patients, included fatigue and vertigo. A comparison of the rates calculated in this meta-analysis to the active arm of equivalent RCTs revealed no significant difference.

CONCLUSION

CNB achieves a good treatment response in patients with DRE in real-world settings, like the effect reported in RCTs. The high heterogeneity between studies calls for studies focusing on specific DRE subpopulations.

Frontline Sodium Channel-Blocking Antiseizure Medicine Use Promotes Future Onset of Drug-Resistant Chronic Seizures

The mechanisms of treatment-resistant epilepsy remain unclear. We have previously shown that frontline administration of therapeutic doses of lamotrigine (LTG), which preferentially inhibits the fast-inactivation state of sodium channels, during corneal kindling of mice promotes cross-resistance to several other antiseizure medicines (ASMs). However, whether this phenomenon extends to monotherapy with ASMs that stabilize the slow inactivation state of sodium channels is unknown. Therefore, this study assessed whether lacosamide (LCM) monotherapy during corneal kindling would promote future development of drug-resistant focal seizures in mice. Male CF-1 mice (n = 40/group; 18-25 g) were administered an anticonvulsant dose of LCM (4.5 mg/kg, i.p.), LTG (8.5 mg/kg, i.p.), or vehicle (0.5% methylcellulose) twice daily for two weeks during kindling. A subset of mice (n = 10/group) were euthanized one day after kindling for immunohistochemical assessment of astrogliosis, neurogenesis, and neuropathology. The dose-related antiseizure efficacy of distinct ASMs, including LTG, LCM, carbamazepine, levetiracetam, gabapentin, perampanel, valproic acid, phenobarbital, and topiramate, was then assessed in the remaining kindled mice. Neither LCM nor LTG administration prevented kindling: 29/39 vehicle-exposed mice were kindled; 33/40 LTG-exposed mice were kindled; and 31/40 LCM-exposed mice were kindled. Mice administered LCM or LTG during kindling became resistant to escalating doses of LCM, LTG, and carbamazepine. Perampanel, valproic acid, and phenobarbital were less potent in LTG- and LCM-kindled mice, whereas levetiracetam and gabapentin retained equivalent potency across groups. Notable differences in reactive gliosis and neurogenesis were also appreciated. This study indicates that early, repeated administration of sodium channel-blocking ASMs, regardless of inactivation state preference, promotes pharmacoresistant chronic seizures. Inappropriate ASM monotherapy in newly diagnosed epilepsy may thus be one driver of future drug resistance, with resistance being highly ASM class specific.

Effects of Mexiletine and Lacosamide on Nerve Excitability in Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study

Selective voltage-gated sodium channel blockers are of growing interest as treatment for pain. For drug development of such compounds, it would be critical to have a biomarker that can be used for proof-of-mechanism. We aimed to evaluate whether drug-induced changes in sodium conductance can be detected in the peripheral nerve excitability profile in 18 healthy subjects. In a randomized, double-blind, 3-way crossover study, effects of single oral doses of 333 mg mexiletine and 300 mg lacosamide were compared with placebo. On each study visit, motor and sensory nerve excitability measurements of the median nerve were performed (predose; and 3 and 6 hours postdose) using Qtrac. Treatment effects were calculated using an analysis of covariance (ANCOVA) with baseline as covariate. Mexiletine and lacosamide had significant effects on multiple motor and sensory nerve excitability variables. Depolarizing threshold electrotonus (TEd₄₀ (40-60 ms)) decreased by mexiletine (estimated difference (ED) -1.37% (95% confidence interval (CI): -2.20, -0.547; P = 0.002) and lacosamide (ED -1.27%, 95% CI: -2.10, -0.443; P = 0.004) in motor nerves. Moreover, mexiletine and lacosamide decreased superexcitability (less negative) in motor nerves (ED 1.74%, 95% CI: 0.615, 2.87; P = 0.004, and ED 1.47%, 95% CI: 0.341, 2.60; P = 0.013, respectively). Strength-duration time constant decreased after lacosamide in motor- (ED -0.0342 ms, 95% CI: -0.0571, -0.0112; P = 0.005) and sensory nerves (ED -0.0778 ms, 95% CI: -0.116, -0.0399; P < 0.001). Mexiletine and lacosamide significantly decrease excitability of motor and sensory nerves, in line with their suggested mechanism of action. Results of this study indicate that nerve excitability threshold tracking can be an effective pharmacodynamic biomarker. The method could be a valuable tool in clinical drug development.

Evaluation of Cardiovascular Concerns of Intravenous Lacosamide Therapy in Epilepsy Patients

Objective

Voltage-gated sodium channels (VGSCs) play an important role in neuronal excitability and epilepsies. In addition to the brain, VGSCs are also abundant enriched in cardiac tissues and are responsible for normal cardiac rhythm. Theoretically, sodium channel blocking antiseizure medications (SCB-ASMs) may have unwanted cardiac side effects. Lacosamide (LCM) is increasingly used in patients with status epilepticus (SE) due to the availability of intravenous formula. The concerns about the proarrhythmic effect are even higher due to the need for rapid administration of LCM. There were limited data on the cardiac safety of intravenous LCM. Hereby, we performed a study to observe the effect of intravenous loading of LCM in patients with seizures in our Neurological Intensive Care Unit (NICU).

Methods

We retrospectively reviewed the patients using parenteral LCM for seizures in NICU. A routine infusion time of 30 min was performed. The electrocardiogram (ECG) and blood pressure were recorded before and after LCM injection.

Results

We retrospectively reviewed the clinical data of 38 patients using LCM for treating seizures. Two patients had cardiac side effects after LCM loading, one (3.0%) with new-onset first-degree AV block and the other (3.0%) with atrial premature complex. For the quantitative changes of ECG parameter analysis, there was no change in QRS complex, corrected QT intervals, and heart rate except that the PR interval was mildly increased. A mild decrease in the diastolic blood pressure and mean arterial pressure were also observed. None of the above-mentioned parameter alterations required clinical intervention.

Conclusion

We evaluated the cardiac safety concern in real-world epilepsy patients requiring intravenous LCM. Near half of this cohort responded to LCM therapy and there was no life-threatening cardiac adverse effect. Intravenous LCM does have some effects on the ECG parameters and blood pressure but without clinical relevance. Despite the theoretical concern of cardiac adverse effects of LCM, the benefit of seizure control outweighed the risk in patients with status epilepticus or seizure clusters, such as hyperthermia, pulmonary edema, cardiac arrhythmias, or cardiovascular collapse.

A Review of the Selected and Newer Antiseizure Medications Used in Childhood Epilepsies

There have been additions of newer antiseizure medications in the armamentarium of clinicians for the management of epilepsy. The newer antiseizure medications have advantages of better tolerability, lesser adverse effects, and minimal drug interactions in comparison with conventional antiseizure medications. However, high cost and availability are concerns. There are also peculiar pharmacokinetic and pharmacodynamic considerations for the pediatric age, particularly in the context of age-dependent electroclinical syndromes and precision-based medicine. This review attempts to provide a comprehensive and pragmatic update on newer antiseizure medications.

Neurocognitive Effects of Antiseizure Medications in Children and Adolescents with Epilepsy

Impairments in cognition are common in epilepsy and may be caused or exacerbated by antiseizure medications (ASMs). Positive effects on cognition may also be seen with some ASMs. Cognitive outcomes are of particular concern in children who may be at an increased risk of cognitive adverse effects of treatment. A comprehensive literature search was conducted in PubMed in order to evaluate the evidence for cognitive changes associated with treatment with ASMs in paediatric epilepsy patients. The ASMs considered were those in the current edition of the British National Formulary (BNF). For most ASMs, remarkably few studies providing robust data on cognitive effects in paediatric patients were identified. The available evidence suggests cognitive impairments may be associated with treatment with phenobarbital. Topiramate and phenytoin are also associated with negative effects on cognition, in particular word-finding difficulties and other language deficits with topiramate, but there are few data available specifically on children. Lamotrigine, levetiracetam and fenfluramine are associated with improvements in some cognitive domains, although it is unclear whether these effects are directly attributable to the medications or are a result of improvements in seizures. Neutral effects on cognition (no substantial evidence of worsening) were suggested for carbamazepine, everolimus, lacosamide, oxcarbazepine, perampanel and valproate. There is limited data for cannabidiol, clobazam, eslicarbazepine acetate, ethosuximide, rufinamide, vigabatrin and zonisamide, although the available evidence suggests these drugs are not associated with severe cognitive impairment. There was too little information to reach conclusions about the effects of brivaracetam, felbamate, gabapentin, pregabalin, retigabine, stiripentol or tiagabine.

The subiculum and its role in focal epileptic disorders

The subicular complex (hereafter referred as subiculum), which is reciprocally connected with the hippocampus and rhinal cortices, exerts a major control on hippocampal outputs. Over the last three decades, several studies have revealed that the subiculum plays a pivotal role in learning and memory but also in pathological conditions such as mesial temporal lobe epilepsy (MTLE). Indeed, subicular networks actively contribute to seizure generation and this structure is relatively spared from the cell loss encountered in this focal epileptic disorder. In this review, we will address: (i) the functional properties of subicular principal cells under normal and pathological conditions; (ii) the subiculum role in sustaining seizures in in vivo models of MTLE and in in vitro models of epileptiform synchronization; (iii) its presumptive role in human MTLE; and (iv) evidence underscoring the relationship between subiculum and antiepileptic drug effects. The studies reviewed here reinforce the view that the subiculum represents a limbic area with relevant, as yet unexplored, roles in focal epilepsy.

New Methods Used in Pharmacokinetics and Therapeutic Monitoring of the First and Newer Generations of Antiepileptic Drugs (AEDs)

The review presents data from the last few years on bioanalytical methods used in therapeutic drug monitoring (TDM) of the 1st-3rd generation and the newest antiepileptic drug (AEDs) cenobamate in patients with various forms of seizures. Chemical classification, structure, mechanism of action, pharmacokinetic data and therapeutic ranges for total and free fractions and interactions were collected. The primary data on bioanalytical methods for AEDs determination included biological matrices, sample preparation, dried blood spot (DBS) analysis, column resolution, detection method, validation parameters, and clinical utility. In conclusion, the most frequently described method used in AED analysis is the LC-based technique (HPLC, UHPLC, USLC) combined with highly sensitive mass detection or fluorescence detection. However, less sensitive UV is also used. Capillary electrophoresis and gas chromatography have been rarely applied. Besides the precipitation of proteins or LLE, an automatic SPE is often a sample preparation method. Derivatization was also indicated to improve sensitivity and automate the analysis. The usefulness of the methods for TDM was also highlighted.

Status of peripheral sodium channel blockers for non-addictive pain treatment

The effective and safe treatment of pain is an unmet health-care need. Current medications used for pain management are often only partially effective, carry dose-limiting adverse effects and are potentially addictive, highlighting the need for improved therapeutic agents. Most common pain conditions originate in the periphery, where dorsal root ganglion and trigeminal ganglion neurons feed pain information into the CNS. Voltage-gated sodium (Na_V) channels drive neuronal excitability and three subtypes - Na_V1.7, Na_V1.8 and Na_V1.9 - are preferentially expressed in the peripheral nervous system, suggesting that their inhibition might treat pain while avoiding central and cardiac adverse effects. Genetic and functional studies of human pain disorders have identified Na_V1.7, Na_V1.8 and Na_V1.9 as mediators of pain and validated them as targets for pain treatment. Consequently, multiple Na_V1.7-specific and Na_V1.8-specific blockers have undergone clinical trials, with others in preclinical development, and the targeting of Na_V1.9, although hampered by technical constraints, might also be moving ahead. In this Review, we summarize the clinical and preclinical literature describing compounds that target peripheral Na_V channels and discuss the challenges and future prospects for the field. Although the potential of peripheral Na_V channel inhibition for the treatment of pain has yet to be realized, this remains a promising strategy to achieve non-addictive analgesia for multiple pain conditions.

Efficacy and pharmacokinetics evaluation of 4-(2-chloro-4-fluorobenzyl)-3-(2-thienyl)-1,2,4-oxadiazol-5(4H)-one (GM-90432) as an anti-seizure agent

Epilepsy is a common chronic neurological disease characterized by recurrent epileptic seizures. A seizure is an uncontrolled electrical activity in the brain that can cause different levels of behavior, emotion, and consciousness. One-third of patients fail to receive sufficient seizure control, even though more than fifty FDA-approved anti-seizure drugs (ASDs) are available. In this study, we attempted small molecule screening to identify potential therapeutic agents for the treatment of seizures using seizure-induced animal models. Through behavioral phenotype-based screening, 4-(2-chloro-4-fluorobenzyl)-3-(2-thienyl)-1,2,4-oxadiazol-5(4H)-one (GM-90432) was identified as a prototype. GM-90432 treatment effectively decreased seizure-like behaviors in zebrafish and mice with chemically induced seizures. These results were consistent with decreased neuronal activity through immunohistochemistry for pERK in zebrafish larvae. Additionally, electroencephalogram (EEG) analysis revealed that GM-90432 decreases seizure-specific EEG events in adult zebrafish. Moreover, we revealed the preferential binding of GM-90432 to voltage-gated Na⁺ channels using a whole-cell patch clamp technique. Through pharmacokinetic analysis, GM-90432 effectively penetrated the blood-brain barrier and was distributed into the brain. Taken together, we suggest that GM-90432 has the potential to be developed into a new ASD candidate.

Therapeutic Monitoring of Lacosamide in Japanese Patients With Epilepsy: Clinical Response, Tolerability, and Optimal Therapeutic Range

BACKGROUND

Lacosamide is a novel anticonvulsant that acts by enhancing sodium channel slow inactivation. The aims of this study were to evaluate the influence of concomitant antiepileptic drugs (AEDs) on serum lacosamide concentration and explore the relationship between lacosamide serum concentration and both clinical response and adverse effects.

METHODS

The authors analyzed 649 serum samples from 426 Japanese patients with epilepsy. The concentration-to-dose (CD) ratio of lacosamide was compared among patients on various AED regimens. Clinical information about seizure frequency and adverse events was obtained from clinical records.

RESULTS

In patients who did not receive enzyme-inducing AEDs, the CD ratio (mean ± SD) of lacosamide was 1.84 ± 0.68. By contrast, the CD ratio in patients who received phenytoin, carbamazepine, and phenobarbital was 1.42 ± 0.66 (22.8% lower), 1.46 ± 0.40 (20.7% lower), and 1.36 ± 0.38 (26.1% lower), respectively. Seventy-four patients (17.3%) achieved >50% seizure reduction. The median lacosamide concentration in patients who received and did not receive a sodium channel blocker was 6.6 mcg/mL (26.4 μmol/L) and 8.4 mcg/mL (33.6 μmol/L), respectively. Adverse events, including dizziness, somnolence, diplopia, and anorexia, were reported by 70 patients (16.4%). The incidence rate in patients treated with sodium channel blockers was significantly higher than that in patients not treated with these drugs (21.1% vs. 10.3%; P < 0.005), and the median lacosamide concentration in these patient groups was 5.1 (20.4 μmol/L) and 7.5 mcg/mL (30 μmol/L), respectively.

CONCLUSIONS

Therapeutic drug monitoring of lacosamide is clinically useful because it allows physicians to estimate the extent of drug interactions and adjust the dose in individual AED regimens.

Discovery of Vixotrigine: A Novel Use-Dependent Sodium Channel Blocker for the Treatment of Trigeminal Neuralgia

Drugs that block voltage-gated sodium channels (NaVs) have utility in treating conditions including pain, epilepsy, and cardiac arrhythmias and as anesthetics (Lancet Neurol.20109413424; Expert Opin. Ther. Pat.201020755779). The identification of compounds with improved efficacy and safety is a key aim for the discovery of improved NaV blocking drugs (Comprehensive Medicinal Chemistry III; (Elsevier, 2017; pp 131-175). We report the identification of a novel class of brain penetrant and voltage-gated sodium channel blockers, leading to the discovery of vixotrigine, a use-dependent sodium channel blocker with activity in in vivo models of pain. Vixotrigine has excellent physiocochemical properties for drug development, and both preclinical and clinical data support a safety profile suitable for potential use in neuropathic pain and other conditions. It has shown efficacy in a Phase II study for pain associated with trigeminal neuralgia.

Safety and tolerability profile of new antiepileptic drug treatment in children with epilepsy

INTRODUCTION

Treatment of pediatric epilepsy requires a careful evaluation of the safety and tolerability profile of antiepileptic drugs (AEDs) to avoid or minimize as much as possible adverse events (AEs) on various organs, hematological parameters, and growth, pubertal, motor, cognitive and behavioral development.

AREAS COVERED

Treatment-emergent AEs (TEAEs) reported in the literature 2000-2018 regarding second- and third-generation AEDs used in the pediatric age, with exclusion of the neonatal period that exhibits specific peculiarities, have been described on the basis of their frequency, severity/tolerability, and particular association with a given AED.

EXPERT OPINION

Somnolence/sedation and behavioral changes, like irritability and nervousness, are among the most commonly observed TEAEs associated with almost all AEDs. Lamotrigine, Gabapentin, Oxcarbazepine, and Levetiracetam appear to be the best-tolerated AEDs with a ≤2% withdrawal rate, while Tiagabine and Everolimus are discontinued in up to >20% of the patients because of intolerable TEAEs. For some AEDs, literature data are scanty to draw a high-level evidence on their safety and tolerability profile. The reasons are: insufficient population size, short duration of treatments, or lack of controlled trials. A future goal is that of identifying clearer, easier, and more homogeneous methodological strategies to facilitate AED testing in pediatric populations.

Epilepsy and ion channels

Many mutations of genes for ion channels result in some epilepsies. Their electrophysiological studies reveal pathophysiological mechanisms underlining epilepsy and also mechanism of action of several antiepileptic drugs. In this review, We briefly summarize pathophysiology of epilepsy and the mechanisms of antiepileptic drugs.

Cytisine inhibits the protective activity of various classical and novel antiepileptic drugs against 6 Hz-induced psychomotor seizures in mice

BACKGROUND

Cytisine (CYT) is a partial agonist of brain α4β2 nicotinic acetylcholine receptors widely used in Central/Eastern Europe for smoking cessation.

OBJECTIVES

This study evaluated the effect of CYT on the ability of classical and novel antiepileptic drugs to prevent seizures evoked by the 6-Hz test, a model of psychomotor seizures in mice thought as a model of drug-resistant seizures.

RESULTS

CYT administered intraperitoneally (i.p.) in a dose of 2 mg kg^-1 significantly inhibited the anticonvulsant activity of lacosamide, levetiracetam, and pregabalin, increasing their median effective doses 50 (ED₅₀) values from 6.88 to 10.52 mg kg^-1 (P < 0.05) for lacosamide, from 22.08 to 38.26 mg kg^-1 (P < 0.05) for levetiracetam, and from 40.48 to 64.61 mg kg^-1 (P < 0.01) for pregabalin, respectively. There were no significant changes in total brain concentrations of lacosamide, levetiracetam, and pregabalin following CYT i.p. administration. CYT administered in a dose of 2 mg kg^-1 failed to change the protective action of clobazam, clonazepam, phenobarbital, tiagabine, and valproate in the 6-Hz test. Neither CYT (2 mg kg^-1) alone nor its combination with the anticonvulsant drugs (at their ED₅₀ values from the 6-Hz test) affected motor coordination; skeletal muscular strength and long-term memory, as determined in the chimney; and grip strength and passive avoidance tests, respectively.

CONCLUSION

CYT-evoked alterations in the protection provided by some antiepileptic drugs against seizures can be of serious concern for epileptic smokers, who might demonstrate therapeutic failure to lacosamide, levetiracetam, and pregabalin, resulting in possible breakthrough seizure attacks.

Intravenous lacosamide in seizure emergencies: Observations from a hospitalized in-patient adult population

PURPOSE

to evaluate the efficacy and safety of intravenous (IV) lacosamide (LCM) in the treatment of seizure clusters (SC) and status epilepticus (SE) in hospitalized adult patients.

METHODS

we prospectively analyzed treatment response, seizure outcome, and adverse effects of IV LCM in 38 patients with seizure emergencies (15 with SC, 23 with SE) during a hospital stay. The loading dose of IV LCM was 200-400mg and the maintenance dose was 200-400mg daily. Response to IV LCM was evaluated within 20min, 4h and 24h of LCM infusion.

RESULTS

an acute anti-seizure effect after IV LCM was especially evident when it was first used - (SC) or second line (established SE) treatment. In particular, 87% of SC patients (13/15) and 80% of established SE (8/10) demonstrated response to LCM treatment, while no patients with super-refractory SE (0/8) responded to IV LCM according to our criteria. The loading of IV LCM was well tolerated, with mild adverse effects (2/38 temporary dizziness). In most patients, during and after administration of the loading dose of IV LCM a temporary (30min-1h) sedation was observed. No ECG and laboratory values-changes were documented in any of the patients.

CONCLUSIONS

LCM is an effective and well-tolerated treatment when used to treat SC in hospitalized adult patients. As add-on therapy, it may be useful to stop seizure activity in patients with focal SE not responding to first/second-line intravenous AEDs.

Anticonvulsant and antinociceptive activity of new amides derived from 3-phenyl-2,5-dioxo-pyrrolidine-1-yl-acetic acid in mice

The aim of the present experiments was to examine the anticonvulsant and antinociceptive activity of five new amides derived from 3-phenyl-2,5-dioxo-pyrrolidine-1-yl-acetic acid in animal models of seizures and pain. The antiseizure activity was investigated in three acute models of seizures, namely, the maximal electroshock (MES), the subcutaneous pentylenetetrazole (scPTZ), and 6Hz psychomotor seizure tests in mice. The antinociceptive properties were estimated in the formalin model of tonic pain, and in the oxaliplatin-induced neuropathic pain model in mice. Considering drug safety evaluation, acute neurological toxicity was determined in the rotarod test. Three tested compounds (3, 4, and 7) displayed a broad spectrum of anticonvulsant activity and showed better protective indices than those obtained for MES/scPTZ/6Hz active reference drug - valproic acid. Furthermore, three compounds (3, 4, and 6) demonstrated a significant antinociceptive effect in the formalin test, as well as antiallodynic activity in the oxaliplatin-induced neuropathic pain model. Among the tested agents, compounds 3 and 4 displayed not only antiseizure properties, but also collateral prominent analgesic properties. The in vitro binding study indicated that the plausible mechanism of action of chosen compound (4) was the influence on neuronal voltage-sensitive sodium (site 2) and L-type calcium channels.

Moving towards effective therapeutic strategies for Neuronal Ceroid Lipofuscinosis

The Neuronal Ceroid Lipofuscinoses (NCLs) are a family of autosomal recessive neurodegenerative disorders that annually affect 1:100,000 live births worldwide. This family of diseases results from mutations in one of 14 different genes that share common clinical and pathological etiologies. Clinically, the diseases are subcategorized into infantile, late-infantile, juvenile and adult forms based on their age of onset. Though the disease phenotypes may vary in their age and order of presentation, all typically include progressive visual deterioration and blindness, cognitive impairment, motor deficits and seizures. Pathological hallmarks of NCLs include the accumulation of storage material or ceroid in the lysosome, progressive neuronal degeneration and massive glial activation. Advances have been made in genetic diagnosis and counseling for families. However, comprehensive treatment programs that delay or halt disease progression have been elusive. Current disease management is primarily targeted at controlling the symptoms rather than "curing" the disease. Recognizing the growing need for transparency and synergistic efforts to move the field forward, this review will provide an overview of the therapeutic approaches currently being pursued in preclinical and clinical trials to treat different forms of NCL as well as provide insight to novel therapeutic approaches in development for the NCLs.

Advances in epilepsy treatment: lacosamide pharmacokinetic profile

Lacosamide (LCM) is a functionalized amino acid specifically developed for use as an antiepileptic drug (AED) and is currently indicated as adjunctive treatment for partial-onset seizures in adults with focal epilepsy (maximum approved dose 400 mg/day). Characterization of the pharmacokinetic profile is an important aspect in the development of LCM. Studies in healthy subjects and in patients with focal epilepsy have established that LCM has several favorable pharmacokinetic characteristics, including rapid absorption and high oral bioavailability not affected by food, linear and dose-proportional pharmacokinetics, low inter- and intraindividual variability, low plasma protein binding, renal elimination, and a low potential for clinically relevant pharmacokinetic drug-drug interactions both with AEDs and other common medications. Studies have demonstrated bioequivalence among the three LCM formulations (oral tablets, oral solution, and solution for intravenous (IV) infusion), allowing direct conversion to or from oral and IV administration without titration. Thus, the favorable and predictable pharmacokinetic profile and bioequivalence of LCM formulations, coupled with the low potential for clinically relevant pharmacokinetic drug-drug interactions, make LCM an easy-to-use adjunctive treatment for the management of patients with focal epilepsy.

Advances in anti-epileptic drug testing

In the past twenty-one years, 17 new antiepileptic drugs have been approved for use in the United States and/or Europe. These drugs are clobazam, ezogabine (retigabine), eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, perampanel, pregabalin, rufinamide, stiripentol, tiagabine, topiramate, vigabatrin and zonisamide. Therapeutic drug monitoring is often used in the clinical dosing of the newer anti-epileptic drugs. The drugs with the best justifications for drug monitoring are lamotrigine, levetiracetam, oxcarbazepine, stiripentol, and zonisamide. Perampanel, stiripentol and tiagabine are strongly bound to serum proteins and are candidates for monitoring of the free drug fractions. Alternative specimens for therapeutic drug monitoring are saliva and dried blood spots. Therapeutic drug monitoring of the new antiepileptic drugs is discussed here for managing patients with epilepsy.

Lacosamide as an adjunctive therapy in pediatric patients with refractory focal epilepsy

PURPOSE

To evaluate the efficacy and safety of lacosamide in pediatric patients with refractory focal epilepsy.

METHODS

We reviewed retrospectively the medical records of children younger than 18 years of age treated at Seoul National University Bundang Hospital, in whom oral lacosamide was used as an adjunctive treatment for refractory focal epilepsy. Clinical information regarding the patients' epilepsy and the outcome of lacosamide treatment was gathered and analyzed.

RESULTS

Twenty-one patients (16 boys, 5 girls) were included, with a median age of 13.9 (range, 1.2-17.9) years. The mean number of concomitant antiepileptic drugs was 3.0 (range, 1-6) and the mean duration of follow-up was 10.1 (range, 6.1-13.0) months. The mean maintenance dose of lacosamide was 5.4 (range, 1.4-9.8) mg/kg/day. Fourteen patients (67%) were responders; four of these were seizure free at the last follow-up. Seven patients (33%) were nonresponders: two of these presented with <50% seizure reduction and five showed no change in seizure frequency. Two patients (10%) discontinued oral lacosamide because of adverse events (aggressive behavior and depression). Mild transient treatment-related adverse events were observed in eight of the 21 patients (38%).

CONCLUSIONS

Lacosamide represents a useful drug that is effective for a wide range of pediatric refractory focal epilepsy and is well tolerated.

Identification and characterization of stress degradants of lacosamide by LC-MS and ESI-Q-TOF-MS/MS: development and validation of a stability indicating RP-HPLC method

The current study dealt with the degradation behavior of lacosamide (LAC) under ICH prescribed stress conditions. LAC was found to be labile under acid and base hydrolytic stress conditions, while it was stable to neutral hydrolytic, oxidative, photolytic and thermal stress. In total, seven degradation products (DPs) were formed, which were separated on a C18 column using a stability-indicating method. LC-MS analyses indicated that one of the DPs had the same molecular mass as that of the drug. Structural characterization of DPs was carried out using ESI-Q-TOF-MS/MS technique. The degradation pathways and mechanisms of degradation of the drug were delineated by carrying out the degradation in different co-solvents viz. methanol, deuterated methanol, ethanol, 1-propanol and acetonitrile. The developed LC method was validated for the determination of related substances and assay of LAC as per ICH guidelines. This study demonstrates a comprehensive approach of LAC degradation studies during its development phase.

Efficacy of lacosamide as adjunctive therapy in children with refractory epilepsy

Lacosamide is a US Food and Drug Administration (FDA)-approved antiepileptic drug for patients 17 years or older with partial epilepsy. There are sparse data on children. The objective of our study was to evaluate its efficacy/safety in children with refractory epilepsy. Forty children (mean age 14.3 years) were treated with lacosamide at our institution (adjunctive therapy in 36, monotherapy in 4). Fifteen patients had symptomatic focal epilepsy, 2 had cryptogenic focal epilepsy, 20 had symptomatic generalized epilepsy, and 3 had cryptogenic generalized epilepsy. Two had juvenile myoclonic epilepsy and 5 had Lennox-Gastaut syndrome. Forty-two percent had at least >50% reduction in seizure frequency, and 6 became seizure free. Average dose was 7 mg/kg/d and average follow-up was 9.2 months. Responders had a 76.5% mean decrease in seizures. Fifteen children experienced an adverse reaction and 7 discontinued lacosamide (4: Ineffective, I: insurance denial, 1: tremor, 1: behavior). Lacosamide is effective and well-tolerated in children with refractory epilepsy.

What are the arguments for and against rational therapy for epilepsy?

Although more than a dozen new anti-seizure drugs (ASDs) have entered the market since 1993, a substantial proportion of patients (~30 %) remain refractory to current treatments. Thus, a concerted effort to identify and develop new therapies that will help these patients continues. Until this effort succeeds, it is reasonable to re-assess the use of currently available therapies and to consider how these therapies might be utilized in a more efficacious manner. This applies to the selection of monotherapies in newly-diagnosed epilepsy, but perhaps, more importantly, to the choice of combination treatments in otherwise drug-refractory epilepsy. Rational polytherapy is a concept that is predicated on the combination of drugs with complementary mechanisms of action (MoAs) that work synergistically to maximize efficacy and minimize the potential for adverse events. Furthermore, rational polytherapy requires a detailed understanding of the MoA subclasses amongst available ASDs and an appreciation of the empirical evidence that supports the use of specific combinations. The majority of ASDs can be loosely categorized into those that target neurotransmission and network hyperexcitability, modulate intrinsic neuronal properties through ion channels, or possess broad-spectrum efficacy as a result of multiple mechanisms. Within each of these categories, there are discrete pharmacological profiles that differentiate individual ASDs. This chapter will consider how knowledge of MoA can help guide therapy in a rational manner, both in the selection of monotherapies for specific seizure types and syndromes, but also in the choice of drug combinations for patients whose epilepsy is not optimally controlled with a single ASD.

Clinical experience with using lacosamide for the treatment of epilepsy in a tertiary centre

OBJECTIVE

Lacosamide is approved for the adjunctive treatment of partial-onset seizures in adults. Phase II/III clinical trials suggest that it is a safe, effective and well-tolerated medication. However, there is little post-marketing information available about this medication.

METHODS

We report our clinical experience from a tertiary referral epilepsy centre, which has been using lacosamide for the past 18 months, with 128 patients treated during this time.

RESULTS

Fifty-three patients (41%) achieved at least a 50% reduction in seizure frequency, with 14 patients (11%) achieving seizure freedom for a mean time of 35 weeks. This 50% responder rate matches, and the seizure free rate outperforms that seen in previous pooled trials. The efficacy of lacosamide did not vary with concurrent sodium channel blocking agent (SCB) use, and a statistically significant dose-dependent response was not shown, which is in contrast to previous trials. Treatment emergent adverse effects (TEAEs) were noted in 52 patients (41%), with 24 patients (19%) discontinuing the medication. TEAEs were more frequent in patients on concurrent SCBs, affecting 51% vs. 28% of patients not on other SCBs. This increased risk of TEAEs from concurrent SCB use was of statistical significance (P = 0.01). The most frequently noted TEAEs from lacosamide were dizziness, sedation and diplopia, which all appeared to be dose-related.

CONCLUSION

This post-marketing analysis suggests that lacosamide in clinical practice at least mirrors, and possibly outperforms the results seen in previous phase II/III trials.

Low-dose lacosamide-induced atrial fibrillation: Case analysis with literature review

Lacosamide (LCM) is a novel antiepileptic drug (AED) approved by the FDA for adjunctive treatment of partial epilepsy with and without secondary generalization. Lacosamide dose-dependent dysrhythmias (PR-interval prolongation, AV block, and atrial fibrillation/flutter) have been reported. This case represents the first instance of LCM-induced atrial fibrillation following a low loading dose (200 mg). Risk factors for atrial fibrillation are addressed and discussed in the context of this case. Full cardiac history is recommended prior to patients being initiated on LCM. Cardiac monitoring may be required for at-risk patients on LCM. Clinicians need to be cognizant of this potential adverse effect.

Pharmacotherapy of the third-generation AEDs: lacosamide, retigabine and eslicarbazepine acetate

INTRODUCTION

The search for new, more effective antiepileptic drugs (AEDs) continues. The three most recently approved drugs, the so-called third-generation AEDs, include lacosamide, retigabine and eslicarbazepine acetate and are licensed as adjunctive treatment of partial epilepsy in adults.

AREAS COVERED

For the above three AEDs, their mechanisms of action, pharmacokinetic characteristics, drug-drug interactions, pharmacotherapeutics, dose and administration and therapeutic drug monitoring are reviewed in this paper.

EXPERT OPINION

Lacosamide and retigabine act through novel mechanisms, while eslicarbazepine acetate, a pro-drug for eslicarbazepine, acts in a similar manner to several other AEDs. All three AEDs are associated with linear pharmacokinetic and rapid absorption and undergo metabolism. Their drug-drug interaction profile is low (lacosamide and retigabine) to modest (eslicarbazepine) in propensity. At the highest approved doses for the three AEDs, responder rates were similar. The most commonly observed adverse effects compared with placebo were dizziness, headache, diplopia and nausea for lacosamide; dizziness, somnolence and fatigue for retigabine and dizziness and somnolence for eslicarbazepine acetate. The precise role that these new AEDs will have in the treatment of epilepsy and whether they will make a significant impact on the prognosis of intractable epilepsy is not yet known and will have to await further clinical experience.

Prevention of posttraumatic axon sprouting by blocking collapsin response mediator protein 2-mediated neurite outgrowth and tubulin polymerization

Epileptogenesis following traumatic brain injury (TBI) is likely due to a combination of increased excitability, disinhibition, and increased excitatory connectivity via aberrant axon sprouting. Targeting these pathways could be beneficial in the prevention and treatment of posttraumatic epilepsy. Here, we tested this possibility using the novel anticonvulsant (R)-N-benzyl 2-acetamido-3-methoxypropionamide ((R)-lacosamide [LCM]), which acts on both voltage-gated sodium channels and collapsin response mediator protein 2 (CRMP2), an axonal growth/guidance protein. LCM inhibited CRMP2-mediated neurite outgrowth, an effect phenocopied by CRMP2 knockdown. Mutation of LCM-binding sites in CRMP2 reduced the neurite inhibitory effect of LCM by ∼8-fold. LCM also reduced CRMP2-mediated tubulin polymerization. Thus, LCM selectively impairs CRMP2-mediated microtubule polymerization, which underlies its neurite outgrowth and branching. To determine whether LCM inhibits axon sprouting in vivo, LCM was injected into rats subjected to partial cortical isolation, an animal model of posttraumatic epileptogenesis that exhibits axon sprouting in cortical pyramidal neurons. Two weeks following injury, excitatory synaptic connectivity of cortical layer V pyramidal neurons was mapped using patch clamp recordings and laser scanning photostimulation of caged glutamate. In comparison with injured control animals, there was a significant decrease in the map size of excitatory synaptic connectivity in LCM-treated rats, suggesting that LCM treatment prevented enhanced excitatory synaptic connectivity due to posttraumatic axon sprouting. These findings suggest, for the first time, that LCM's mode of action involves interactions with CRMP2 to inhibit posttraumatic axon sprouting.

Lacosamide treatment of juvenile myoclonic epilepsy

Juvenile myoclonic epilepsy is the most common form of idiopathic generalized epilepsy with onset at puberty or late teenage years. About 80-90% of patients with juvenile myoclonic epilepsy respond to appropriate antiepileptic treatment and achieve seizure freedom, and about 15% of patients become intractable. Valproic acid, levetiracetam, lamotrigine, topiramate and zonisamide are used as first line or adjunctive therapy of this disorder. Lacosamide is approved for adjunctive treatment of partial onset epilepsies. The role of lacosamide in treatment of idiopathic generalized epilepsy including juvenile myoclonic epilepsy is unknown. We present three patients with classic clinical and electrographic features of juvenile myoclonic epilepsy that were maintained on lacosamide (one on monotherapy and two as adjuvant therapy). There were no special pharmacodynamic actions causing exacerbation or worsening of myoclonic jerks or generalized seizures in these three patients. In conclusion, although, the data from our three patients' suggest that lacosamide may be effective in the treatment of juvenile myoclonic epilepsy, larger studies are needed to explore efficacy and role of lacosamide in the treatment of this disorder.

Preliminary efficacy and safety of lacosamide in children with refractory epilepsy

BACKGROUND

Despite the introduction of multiple new antiepileptic drugs (AEDs) in the past 20 years, about 30% of patients with epilepsy continue to experience uncontrolled seizures or significant side effects.

AIMS

To present our experience with lacosamide therapy in children with drug-resistant epilepsy.

METHODS

We retrospectively reviewed the medical charts of all patients receiving oral lacosamide until October 2010. Efficacy was determined according to seizure frequency during the week prior to treatment initiation and the week after the maximal dosage of lacosamide was attained.

RESULTS

Seventeen patients (10 boys) aged 1.5-16 (mean - 8 ± 4.7) years were identified. Nine patients had epilepsy attributed to a structural cause, six patients had epilepsy of unknown cause, and two had Lennox-Gastaut syndrome. Mean epilepsy duration was 5.4 ± 3.3 years. The mean number of previous AEDs was 6.6 ± 2. Lacosamide was added to the baseline AEDs in13 patients. The mean duration of follow-up was 9.1 ± 4.4 months. Six (35%) patients had at least a 50%.seizure reduction (mean - 76%). Social, behavioral, and/or motor improvement were noted in seven (41%) patients. Lacosamide was discontinued in six (35%) patients because of inefficacy. Side effects were reported in 10 (59%) patients.

CONCLUSIONS

Lacosamide seems to be effective and safe according to the data in our small cohort. Further prospective studies on lacosamide efficacy and safety in a large number of children are warranted.

Newer anticonvulsant medications in pediatric neurology

OPINION STATEMENT

Antiepileptic drugs (AEDs) are the mainstay of treatment for recurrent seizures. Uncontrolled seizures may cause medical, developmental, and psychological disturbances. The medical practitioner should thus strive to eliminate or minimize seizures. Treatment advances in epilepsy include 1) identification of the basic mechanisms of epilepsy and action of AEDs, 2) the introduction of new AEDs, and 3) the use of neurostimulation, including vagus nerve stimulation. Treatment with AEDs involves balancing each AED's efficacy against its side effects. In some patients, effective AEDs must be discontinued because of intolerable side effects. Although all AEDs have a proven efficacy, the choice of AEDs should be based on better efficacy for individual seizure types or epilepsy syndromes. Side effects also differ from drug to drug and must be taken into account. This article focuses on studies and expert opinion consensus to guide the choice of AEDs.