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SummaryObjectivePharmacokinetics (PK) of a drug drive its exposure, efficacy, and tolerability. A thorough preclinical PK assessment of antiseizure medications (ASMs) is therefore essential to evaluate the clinical potential. We tested protection against evoked seizures of prototype ASMs in conjunction with analysis of plasma and brain PK as a proof-of-principle study to enhance our understanding of drug efficacy and duration of action using rodent seizure models.MethodsIn vivo seizure protection assays were performed in adult male CF-1 mice and Sprague-Dawley rats. Clobazam (CLB), N-desmethylclobzam (NCLB), carbamazepine (CBZ), carbamazepine-10,11-epoxide (CBZE), valproic acid (VPA), and levetiracetam (LEV) concentrations were quantified in plasma and brain using liquid chromatography-tandem mass spectrometry. Mean concentrations of each analyte were calculated and used to determine PK parameters via non-compartmental analysis in Phoenix WinNonLin.ResultsNCLB concentrations were approximately 10-fold greater than CLB in mice. The antiseizure profile of CLB was partially sustained by NCLB in mice. CLB concentrations were lower in rats than in mice. CBZE plasma exposures were approximately 70% of CBZ in both mice and rats, likely contributing to the antiseizure effect of CBZ. VPA showed a relatively short half-life in both mice and rats, which correlated with a sharp decline in efficacy. LEV had a prolonged brain and plasma half-life, associated with a prolonged duration of action in mice.SignificanceThe study demonstrates the utility of PK analyses for understanding the seizure protection time-course in mice and rats. The data indicate that distinct PK profiles of ASMs between mice and rats likely drive differences in drug efficacy between rodent models.Key PointsThere exist potential contributions of active metabolites to the efficacy of some ASMs.The utility of preclinical PK assessment of ASM is critical to guide our insight into a drug efficacy profile and provide a framework for subchronic dosing strategies.Species-specific variations in PK profiles of ASMs in rodent models of epilepsy may underpin the differences in antiseizure effect in these models.Pre-clinical drug screening of ASMs should include a (sub)chronic dosing paradigm to better mimic the dosing regimen in the clinic.

The US Food and Drug Administration (FDA) has concluded that the efficacy of drugs approved for the treatment of partial onset seizures (POS) in adults can be extrapolated to pediatric patients 1 month of age and above and that independent efficacy trials in this pediatric population are no longer needed. This paper focuses on the dosing, pharmacokinetic (PK), exposure-response, and clinical information that were leveraged from the approved drugs for the treatment of POS to conduct analyses that supported extrapolation of efficacy in pediatric patients. Clinical data from trials for eight drugs (levetiracetam, oxcarbazepine, topiramate, lamotrigine, gabapentin, perampanel, tiagabine, and vigabatrin) approved in both adults and pediatric patients for the treatment of POS were analyzed. Comparisons of exposures at approved doses, placebo response, and model-based exposure-response relationships were performed. Based on disease similarity, similar response to intervention, and similar exposure-response relationships in adults and pediatric patients, it was concluded that extrapolation of efficacy in pediatric patients aged 1 month and above is acceptable. PK analysis to determine pediatric dose and regimens that provide drug exposure similar to that known to be effective in adult patients with POS will be required, along with long-term open-label safety data in pediatric patients.

Epilepsy is a chronic disease caused by sudden abnormal discharge of brain neurons, leading to transient brain dysfunction. Levetiracetam, developed by the UCB company in Belgium, is an effective drug for the treatment of epilepsy. (S)-Methyl 2-chlorobutanoate is an important chiral building block of levetiracetam, which has attracted a great deal of attention. In this study, a strain of lipase-produced Acinetobacter sp. zjutfet-1 was screened from soil samples. At optimized conditions for fermentation and biocatalysis, the bacterial lipase exhibited high catalytic activity for hydrolysis and stereoselectivity toward racemic methyl 2-chlorobutanoate. When the enzymatic reaction was carried out in 6% of racemic substrate, the enantiomeric excess (e.e.

Epilepsy is a common diagnosis and can quickly progress to status epilepticus which requires rapid treatment. Levetiracetam is a frequent treatment choice in these situations. The approved administration of intravenous levetiracetam is an infusion over 15 min. In recent years, studies have been published on faster infusion rates of levetiracetam. The objective of this review is to discuss the safety of levetiracetam as an intravenous push at a rate quicker than recommended. A literature search using PubMed, Cochrane Library, ClinicalTrials.gov, and Google Scholar resulted in 192 articles. Inclusion criteria consisted of English language, human studies, use of levetiracetam administered intravenously at a rate faster than 15 min, discussion of safety, and full-text availability. After screening, nine articles remained for inclusion. Of the nine articles, one was a prospective, open-label study, six were retrospective studies, and two were open-label, randomized controlled trials. The most common rapid infusion speed was 5 min and doses ranged from 280 to 4500 mg. Some of these trials used undiluted levetiracetam and many reported that peripheral access was used for a portion or all of the administrations. There were few adverse effects, including specific adverse effects relating to medication concentration and speed of infusion, in all the studies. Administration of intravenous levetiracetam at a rate faster than recommended in the labeling information appears to be safe and tolerable and can be given via a peripheral line. Rapid infusion of levetiracetam is a beneficial method of administration in an acute care setting where patients need rapid attainment of therapeutic levels of antiepileptic medications. Additional research is needed to ensure that rapid administration of intravenous levetiracetam is as efficacious as the traditional dosing method.

This multicenter, open-label, randomized study (Registration No. ChiCTR-OCH-14004528) aimed to compare the efficacy and effects of oxcarbazepine (OXC) with levetiracetam (LEV) as monotherapies on patient quality of life and mental health for patients with newly diagnosed focal epilepsy from China.Patients with newly diagnosed focal epilepsy who had experienced 2 or more unprovoked seizures at greater than a 24-h interval during the previous year were recruited. Participants were randomly assigned to the OXC group or LEV group. Efficacy, safety, quality of life, and mental health were evaluated over 12-week and 24-week periods.In total, we recruited 271 newly diagnosed patients from 23 centers. Forty-four patients were excluded before treatment for reasons. The rate of seizure freedom of OXC was significantly superior to that of LEV at 12 weeks and 24 weeks (p 0.05). The quality of life (except for the seizure worry subsection) and anxiety scale scores also showed significant differences from before to after treatment in the OXC and LEV groups.OXC monotherapy may be more effective than LEV monotherapy in patients with newly diagnosed focal epilepsy. Both OXC and LEV could improve the quality of life and anxiety state in adult patients with focal epilepsy.

This study was undertaken to characterize antiseizure medication (ASM) treatment pathways in Medicare beneficiaries with newly treated epilepsy.This was a retrospective cohort study using Medicare claims. Medicare is the United States' federal health insurance program for people aged 65 years and older plus younger people with disabilities or end-stage renal disease. We included beneficiaries with newly treated epilepsy (International Classification of Diseases codes for epilepsy/convulsions 2014-2017, no ASM in the previous 2 years). We displayed the sequence of ASM fills using sunburst plots overall, then stratified by mood disorder, age, and neurologist prescriber. We tabulated drug costs for each pathway.We included 21 458 beneficiaries. Levetiracetam comprised the greatest number of pill days (56%), followed by gabapentin (11%) and valproate (8%). There were 22 288 unique treatment pathways. The most common pathways were levetiracetam monotherapy (43%), gabapentin monotherapy (10%), and valproate monotherapy (5%). Gabapentin was the most common second- and third-line ASM. Whereas only 2% of pathways involved first-line lacosamide, those pathways accounted for 19% of cost. Gabapentin and valproate use was increased and levetiracetam use was decreased in beneficiaries with mood disorders compared to beneficiaries without mood disorders. Levetiracetam use was increased and gabapentin, valproate, lamotrigine, and topiramate use was decreased in beneficiaries aged65 years compared with those aged 65 years or less. Lamotrigine, levetiracetam, and lacosamide use was increased and gabapentin use was decreased in beneficiaries whose initial prescriber was a neurologist compared to those whose prescriber was not a neurologist.Levetiracetam monotherapy was the most common pathway, although substantial heterogeneity existed. Lacosamide accounted for a small percentage of ASMs but a disproportionately large share of cost. Neurologists were more likely to prescribe lamotrigine compared with nonneurologists, and lamotrigine was prescribed far less frequently than may be endorsed by guidelines. Future work may explore patient- and physician-driven factors underlying ASM choices.

Oxcarbazepine (OXZ) and levetiracetam (LEV) are two new generation anti‐epileptic drugs, often co‐administered in children with enzyme‐inducing antiepileptic drugs (EIAEDs). The anti‐epileptic effect of OXZ and LEV are linked to the exposure of OXZ’s active metabolite 10‐monohydroxy derivative (MHD) and (the parent) LEV, respectively. However, little is known about the confounding effect of age and EIAEDs on the pharmacokinetics (PKs) of MHD and LEV. To address this knowledge gap, physiologically‐based pharmacokinetic (PBPK) modeling was performed in the PK‐Sim software using literature data from children greater than or equal to 2 years of age. Age‐related changes in clearance (CL) of MHD and LEV were characterized, both in the presence (group 1) and absence (group 2) of concomitant EIAEDs. The drug‐drug interaction effect of EIAEDs was estimated as the difference in CL estimates between groups 1 and 2. PBPK modeling suggests that bodyweight normalized CL (ml/min/kg) is higher in younger children than their older counterparts (i.e., due to an influence of age). Concomitant EIAEDs further increase MHD’s CL to a fixed extent of 25% at any age, but EIAEDs’ effect on LEV’s CL increases with age from 20% (at 2 years) to 30% (at adolescence). Simulations with the maximum recommended doses (MRDs) revealed that children between 2 and 4 years and greater than 4 years, who are not on EIAEDs, are at risk of exceeding the reference exposure range for OXZ and LEV, respectively. This analysis demonstrates the use of PBPK modeling in understanding the confounding effect of age and comedications on PKs in children and adolescents.

Background An open‐label single‐arm phase 2 study was conducted to evaluate the role of levetiracetam as a sensitizer of concurrent chemoradiotherapy (CCRT) for patients with newly diagnosed glioblastoma. This study aimed to determine the survival benefit of levetiracetam in conjunction with the standard treatment for glioblastoma. Methods Major eligibility requirements included histologically proven glioblastoma in the supratentorial region, patients 18 years or older, and Eastern Cooperative Oncology Group (ECOG) performance status of 0–2. Levetiracetam was given at 1,000–2,000 mg daily in two divided doses during CCRT and adjuvant chemotherapy thereafter. The primary and the secondary endpoints were 6‐month progression‐free survival (6mo‐PFS) and 24‐month overall survival (24mo‐OS), respectively. Outcomes of the study group were compared to those of an external control group. Results Between July 2016 and January 2019, 76 patients were enrolled, and 73 patients were included in the final analysis. The primary and secondary outcomes were improved in the study population compared to the external control (6mo‐PFS, 84.9% vs. 72.3%, p = 0.038; 24mo‐OS, 58.0% vs. 39.9%, p = 0.018), but the differences were less prominent in a propensity score‐matched analysis (6mo‐PFS, 88.0% vs. 76.9%, p = 0.071; 24mo‐OS, 57.1% vs. 38.8%, p = 0.054). In exploratory subgroup analyses, some results suggested that patients with ages under 65 years or unmethylated MGMT promoter might have a greater survival benefit from the use of levetiracetam. Conclusions The use of levetiracetam during CCRT in patients with newly diagnosed glioblastoma may result in improved outcomes, but further investigations are warranted., Patients aged less than 65 years exhibited better outcomes with levetiracetam. Patients with unmethylated MGMT promoter possibly have greater benefits from levetiracetam.

Objective Infection with Theiler's Murine Encephalomyelitis Virus (TMEV) in C57Bl/6J mice results in handling-induced seizures and is useful for evaluating compounds effective against infection-induced seizures. However, to date only a few compounds have been evaluated in this model, and a comprehensive study of antiseizure medications (ASMs) has not yet been performed. Furthermore, as the TMEV infection produces marked neuroinflammation, an evaluation of prototype anti-inflammatory compounds is needed as well. Methods Male C57Bl/6J mice were inoculated with TMEV (day 0) followed by daily administrations of test compounds (day 3-7) and subsequent handling sessions (day 3-7). Doses of ASMs, comprising several mechanistic classes, were selected based on previously published data demonstrating the effect of these compounds in reducing seizures in the 6 Hz model of pharmacoresistant seizures. Doses of anti-inflammatory compounds, comprising several mechanistic classes, were selected based on published evidence of reduction of inflammation or inflammation-related endpoints. Results Several prototype ASMs reduced acute seizures following TMEV infection: lacosamide, phenytoin, ezogabine, phenobarbital, tiagabine, gabapentin, levetiracetam, topiramate, and sodium valproate. Of these, phenobarbital and sodium valproate had the greatest effect (>95% seizure burden reduction). Prototype anti-inflammatory drugs celecoxib, dexamethasone, and prednisone also moderately reduced seizure burden. Significance The TMEV model is utilized by the Epilepsy Therapy Screening Program (ETSP) as a tool for evaluation of novel compounds. Compounds reducing seizures in the TMEV comprise distinct mechanistic classes, some with mechanisms of action that extend beyond traditional ASMs.

Objective To report post hoc results on how adjustments to baseline antiseizure medications (ASMs) in a subset of study sites (10 US sites) from a long-term, open-label phase 3 study of adjunctive cenobamate affected tolerability, efficacy, and retention. Methods Patients with uncontrolled focal seizures taking stable doses of one to three ASMs were administered increasing doses of cenobamate (12.5, 25, 50, 100, 150, 200 mg/day) over 12 weeks at 2-week intervals (target dose = 200 mg/day). Further increases to 400 mg/day by 50 mg/day biweekly increments were allowed during maintenance phase. Dose adjustments of cenobamate and concomitant ASMs were allowed. Data were assessed until last visit, at data cut-off, on or after September 1, 2019. Results A total of 240 patients meeting eligibility criteria were assessed (median [max] exposure 30.2 [43.0] months), with 177 patients continuing cenobamate at data cut-off. Most common baseline concomitant ASMs were lacosamide, levetiracetam, lamotrigine, zonisamide, and clobazam. For most baseline concomitant ASMs, ~70% of patients taking that ASM were continuing cenobamate at data cut-off. Patients continuing cenobamate had greater mean ASM dose reductions and percent dose changes from baseline vs those who discontinued. Of patients continuing cenobamate, 24.6% discontinued one or more concomitant ASMs completely. Dose decreases for all concomitant ASMs generally occurred during titration or early maintenance phases and were mostly due to central nervous system (CNS)-related adverse events such as somnolence, dizziness, unsteady gait, and fatigue. Responder rates from ≥50% through 100% for patients continuing cenobamate were generally similar regardless of concomitant ASMs (of those most commonly taken), with ~81% being ≥50% responders and ~12% achieving 100% seizure reduction in the maintenance phase, which lasted up to 40.2 (median = 29.5) months. Significance Concomitant ASM dose reductions were associated with more patients remaining on cenobamate. This is likely due to efficacy and improved tolerability, with overall reduced concomitant drug burden in patients with uncontrolled seizures despite taking one to three baseline concomitant ASMs.

Axicabtagene ciloleucel (axi-cel) is an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved for relapsed or refractory large B-cell lymphoma (R/R LBCL). To reduce axi-cel–related toxicity, several exploratory safety management cohorts were added to ZUMA-1 (NCT02348216), the pivotal phase 1/2 study of axi-cel in refractory LBCL. Cohort 4 evaluated the rates and severity of cytokine release syndrome (CRS) and neurologic events (NEs) with earlier corticosteroid and tocilizumab use. Primary endpoints were incidence and severity of CRS and NEs. Patients received 2 × 106 anti-CD19 CAR T cells/kg after conditioning chemotherapy. Forty-one patients received axi-cel. Incidences of any-grade CRS and NEs were 93% and 61%, respectively (grade ≥ 3, 2% and 17%). There was no grade 4 or 5 CRS or NE. Despite earlier dosing, the cumulative cortisone-equivalent corticosteroid dose in patients requiring corticosteroid therapy was lower than that reported in the pivotal ZUMA-1 cohorts. With a median follow-up of 14·8 months, objective and complete response rates were 73% and 51%, respectively, and 51% of treated patients were in ongoing response. Earlier and measured use of corticosteroids and/or tocilizumab has the potential to reduce the incidence of grade ≥ 3 CRS and NEs in patients with R/R LBCL receiving axi-cel.

Bathing epilepsy is a rare form of reflex epilepsy triggered by bathing in room temperature water. It predominates in boys with a mean age of 15 months and its evolution is benign. Diagnosis of bathing epilepsy requires the exclusion of other paroxysmal disorders triggered by water contact. Video-EEG confirmation of the seizures is necessary to reach a diagnosis of certainty and to allow adequate management. We present the case of a one-year-old boy who experienced recurrent episodes of unresponsiveness and cyanosis while bathing in lukewarm water. The diagnosis of bathing epilepsy was confirmed by the video-EEG recording of a seizure, showing left-sided frontotemporal delta activity with rapid contralateral spread. Therapy with levetiracetam was effective, subsequently allowing bathing without further seizures.

Background Antiseizure drugs (ASDs) are the primary therapy for epilepsy, with more than 20 drugs introduced into clinical practice to date. These drugs are typically grouped by their mechanisms of action and therapeutic spectrum. This article aims to educate non‐neurologists and medical students about the new frontiers in the pharmacology of ASDs and presents the current state of the literature on the efficacy and tolerability of these agents. Methods Randomized controlled trials, observational studies, and evidence‐based meta‐analyses of ASD efficacy and tolerability as initial monotherapy for epileptic seizures and syndromes were identified in PubMed, EMBASE, the Cochrane Library, and Elsevier Clinical Pharmacology. Results The choice of ASD varies primarily according to the seizure type. Practical guidelines for ASD selection in patients with new‐onset and drug‐resistant epilepsy were recently published. The guidelines have shown that the newer‐generation drugs, which have unique mechanistic and pharmacokinetic properties, are better tolerated but have similar efficacy compared with the older drugs. Several ASDs are effective as first‐line monotherapy in focal seizures, including lamotrigine, carbamazepine, phenytoin, levetiracetam, and zonisamide. Valproate remains the first‐line drug for many patients with generalized and unclassified epilepsies. However, valproate should be avoided, if possible, in women of childbearing potential because of teratogenicity. Toxicity profile precludes several drugs from use as first‐line treatment, for example, vigabatrin, felbamate, and rufinamide. Conclusions Antiseizure drugs have different pharmacologic profiles that should be considered when selecting and prescribing these agents for epilepsy. These include pharmacokinetic properties, propensity for drug‐drug interactions, and adverse effects., Antiseizure drugs (ASDs) have many different pharmacologic profiles that are relevant when selecting and prescribing these medications in patients with epilepsy. Some second‐generation ASDs have shown advantages in drug tolerability, drug‐drug interactions, and teratogenicity. Disappointingly, however, none of these medications appear to be more efficacious than first‐generation ASDs.

Aims In breastfeeding women, anti-epileptic therapy can lead to infant toxicities, even with newer anti-epileptic drugs such as levetiracetam. This study assessed levetiracetam breastmilk excretion and its correlation with the maternal oral dose and serum concentrations. Methods Women with epilepsy treated with levetiracetam were recruited to this study and completed a questionnaire. Levetiracetam concentrations were determined in serial breastmilk samples (pre-dose to 12 h post-dose period) and in a single pre-dose maternal serum sample. Results Twenty breastfeeding women and 21 infants (one woman with twins; 16 fully and five partially breastfed infants) participated in this study. The trough breastmilk/serum ratio of levetiracetam was 0.98 ± 0.20. The infant levetiracetam daily dose was 5.39 ± 1.96 and 2.70 ± 0.98 mg. kg-1. d-1 , and the relative infant dose (RID) was 13.8 ± 3.1% and 6.9 ± 1.6% in the fully and partially breastfed infants, respectively. Substantial correlations between the levetiracetam dose, maternal serum and breastmilk trough concentrations, and breastmilk AUC values were found. Three women reported somnolence in their fully breastfed infants, which resolved shortly after switching to partial breastfeeding. All the infants gained weight according to their age. Conclusions Infant levetiracetam exposure via the breastmilk was close to the safety thresholds (trough breastmilk/serum ratio slightly below 1, RID > 10% in fully breastfed infants), and infant somnolescence reports could be related to exposure of the infants to levetiracetam via breastmilk. Further studies are warranted to reveal the short- and long-term safety of levetiracetam in breastfeeding.

Objective Recently, a novel trial design has been proposed to overcome challenges with traditional placebo‐controlled trials of antiepileptic drugs in infants and young children (≥1 month of age) (Auvin S, et al. Epilepsia Open 2019;4:537‐43). The proposed time‐to‐event trial design involves seizure counting by caregivers and allows adjustment of the duration of the baseline period and duration of exposure to placebo or potentially ineffective treatment based on the patient's seizure burden and response. We performed post hoc analyses to mimic this trial design and evaluate its viability. As these analyses required trials with prolonged baseline and treatment periods and diary data, which is not a typical design of trials in infants and young children (1 month to

Estimating early exposure of drugs used for the treatment of emergent conditions is challenging because blood sampling to measure concentrations is difficult. The objective of this work was to evaluate predictive performance of two early concentrations and prior pharmacokinetic (PK) information for estimating early exposure. The performance of a modeling approach was compared with a noncompartmental analysis (NCA). A simulation study was performed using literature‐based models for phenytoin (PHT), levetiracetam (LEV), and valproic acid (VPA). These models were used to simulate rich concentration‐time profiles from 0 to 2 h. Profiles without residual unexplained variability (RUV) were used to obtain the true partial area under the curve (pAUC) until 2 h after the start of drug infusion. From the profiles with the RUV, two concentrations per patient were randomly selected. These concentrations were analyzed under a population model to obtain individual population PK (PopPK) pAUCs. The NCA pAUCs were calculated using a linear trapezoidal rule. Percent prediction errors (PPEs) for the PopPK pAUCs and NCA pAUCs were calculated. A PPE within ±20% of the true value was considered a success and the number of successes was obtained for 100 simulated datasets. For PHT, LEV, and VPA, respectively, the median value of the success statistics obtained using the PopPK approach of 81%, 92%, and 88% were significantly higher than the 72%, 80%, and 67% using the NCA approach (p

Fosphenytoin (FOS) and its active form, phenytoin (PHT), levetiracetam (LEV), and valproic acid (VPA) are commonly used second-line treatments of status epilepticus. However, limited information is available regarding LEV and VPA concentrations following high intravenous doses particularly in young children. The Established Status Epilepticus Treatment Trial (ESETT), a blinded, comparative effectiveness study of FOS, LEV, and VPA for benzodiazepine-refractory status epilepticus provided an opportunity to investigate early drug concentrations. Patients ≥ 2 years who continued to seizure despite receiving adequate doses of benzodiazepines were randomized to FOS, LEV or VPA infused over 10 minutes. A sparse blood sampling approach was used, with up to two samples collected per patient within two hours following drug administration. The objective of this work was to report early drug exposure of PHT, LEV and VPA and plasma protein binding of PHT and VPA. Twenty-seven children with median (interquartile range) age of 4 (2.5, 6.5) years were enrolled. The total plasma concentrations ranged from 69-151.3 μg/mL for LEV, 11.3-26.7 μg/mL for PHT and 126-223 μg/mL for VPA. Free fraction ranged from 4-19% for PHT and 17-51% for VPA. This is the first report in young children of LEV concentrations with convulsive status epilepticus as well as VPA concentrations after a 40 mg/kg dose. Several challenges limited patient enrollment and blood sampling. Additional studies with a larger sample size are required to evaluate the exposure-response relationships in this emergent condition. This article is protected by copyright. All rights reserved.

A male patient with a de novo mutation in the YWHAG gene and mild phenotype is presented. He had normal delivery and normal development, with normal speech and social milestones. At the age of 9 months, myoclonic seizures started, with generalized epileptiform discharges. The child responded well to levetiracetam monotherapy with complete seizure resolution. Levetiracetam was stopped and he remained seizure-free for 10 months. His development was appropriate for age according to psychological evaluation and he attended a regular kindergarten. At the age of approximately 4 years, the seizures reappeared with different semiology of staring with eye blinking. Electroencephalogram (EEG) showed multifocal spikes. Brain magnetic resonance imaging did not reveal any structural abnormality. Genetic analysis revealed a de novo likely pathogenic missense variant in the YWHAG gene (c.619G>A p.Glu207Lys). We compared our case to the other cases published in the literature. Our case is unique in its seizure semiology and evolution of EEG. Moreover, in contrast to our case, the majority of cases described in the literature have dysmorphism and intellectual disability or autistic spectrum disorder. This report emphasizes the phenotypic heterogeneity of YWHAG mutation as is the case in other developmental encephalopathies.

To minimize drug-related toxicity and monitor dosing regimens, an ultra-sensitive, simple and high-throughput analytical method for therapeutic drug monitoring is required. A novel LC-MS/MS bioassay of levetiracetam, lamotrigine and 10-hydroxycarbazepine in human plasma was established. The analytes were separated on a Hypersil GOLD™ CThis method can be used to monitor drug concentrations and decision-making in epileptic patients.

Although seizures are common in prehospital settings, standardized emergency medical services (EMS) treatment algorithms do not exist nationally. We examined nationwide variability in status epilepticus treatment by analyzing 33 publicly available statewide EMS protocols. All adult protocols recommend intravenous benzodiazepines (midazolam, n = 33; lorazepam, n = 23; diazepam, n = 24), 30 recommend intramuscular benzodiazepines (midazolam, n = 30; lorazepam, n = 8; diazepam, n = 3), and 27 recommend intranasal benzodiazepines (midazolam, n = 27; lorazepam, n = 3); pediatric protocols also frequently recommend rectal diazepam (n = 14). Recommended dosages vary widely, and first- and second-line agents are designated in only 18 and 2 states, respectively. Given this degree of variability, standardized national EMS guidelines are needed. ANN NEUROL 2021;89:604-609.

OBJECTIVE This study was undertaken to evaluate the influence that subject-specific factors have on intracranial interictal epileptiform discharge (IED) rates in persons with refractory epilepsy. METHODS One hundred fifty subjects with intracranial electrodes performed multiple sessions of a free recall memory task; this standardized task controlled for subject attention levels. We utilized a dominance analysis to rank the importance of subject-specific factors based on their relative influence on IED rates. Linear mixed-effects models were employed to comprehensively examine factors with highly ranked importance. RESULTS Antiseizure medication (ASM) status, time of testing, and seizure onset zone (SOZ) location were the highest-ranking factors in terms of their impact on IED rates. The average IED rate of electrodes in SOZs was 34% higher than the average IED rate of electrodes outside of SOZs (non-SOZ; p

Objective Antiseizure medications (ASMs) can rarely result in severe, sometimes fatal, cutaneous adverse reactions. To date, few studies have reported on the incidence rates (IRs) of severe cutaneous adverse reactions (SCARs) due to ASM use. This study aimed to determine the IRs of SCAR resulting from the use of seven commonly prescribed ASMs, carbamazepine (CBZ), phenytoin (PHT), oxcarbazepine (OXC), lamotrigine (LMT), zonisamide (ZNS), levetiracetam (LVT), and topiramate (TPM), and to compare the associated risks among the drugs. Methods Using a nationwide health claims database, we selected all the patients prescribed with one of the target ASMs. We defined a SCAR case as the first hospitalization with one of three specific codes provided by the International Classification of Diseases, 10th revision (L511, L512, and L27). We then calculated the IR of SCARs according to each target ASM. Results The IR of SCARs for each ASM was as follows: 870/1 000 000 person-years (PYs) for CBZ, 5750/1 000 000 PYs for PHT, 1490/1 000 000 PYs for OXC, 3860/1 000 000 PYs for LMT, 1540/1 000 000 PYs for ZNS, 830/1 000 000 PYs for LVT, and 400/1 000 000 PYs for TPM. Concomitant use of antibiotics and nonsteroidal anti-inflammatory drugs significantly increased the risk of SCARs with OXC, LVT, or TPM use. Comorbid skin disease was associated with a significantly higher IR of SCARs from CBZ, PHT, OXC, LMT, or LVT use. Significance This is the first study in Asia to determine the IRs of SCARs for various ASMs and compare the rates across drugs using a large dataset. The results from this study should help clinicians select safer ASMs in practice.

Background To study the effect of levetiracetam in treating Sydenham chorea. Methods We retrospectively collected the data of 140 patients diagnosed with Sydenham chorea in the pediatric neurology and pediatric cardiology outpatient clinics of Van Training and Research Hospital between January 2010 and December 2018. Results There were 140 patients, 102 (70%) of whom were girls, with mean age of onset 11.8 ± 2.7 years. Symptomatic treatment was initiated in all patients at the time of diagnosis; this medication was changed during follow up in 15 patients. The most frequently prescribed drugs were haloperidol and sodium (Na) valproate, and the most frequently discontinued one was haloperidol, due to side effects. The second-choice drug was most often levetiracetam. Clinical response often began within the first 2 weeks, with Na valproate (P = 0.002), within 4 weeks with carbamazepine (P = 0.037) but 1-6 months with haloperidol (P = 0.018) and levetiracetam (P = 0.008). Time to full remission was similar with Na valproate, carbamazepine, haloperidol, and levetiracetam (P = 0.276). Our study indicated that levetiracetam was as effective as the other commonly used drugs in the symptomatic treatment of Sydenham chorea. Conclusion Levetiracetam might be an option in the treatment of Sydenham chorea because of its acceptable effect and safety profile. This observation needs further support with evidence obtained through controlled and blinded trials.

Purpose To examine indications for, duration of use, and rate of adverse drug events (ADE) attributable to anticonvulsant initiation, as adjudicated by expert review of electronic health records (EHR) of older adults. Methods We identified a cohort of community dwelling Medicare beneficiaries with linked EHR (aged 65+, continuously enrolled with a large health system/until death between 2012 and 2014, n = 20 945) and drew a stratified EHR review sample (n = 1534). An expert reviewed all records to adjudicate anticonvulsant use, years of use, indication for use, and evidence of ADEs attributable to anticonvulsant initiation. After excluding patients with insufficient EHR data (n = 37; 2%), we reconstructed the cohort using inverse probability weights to resemble the original cohort of eligible beneficiaries (n = 20 380). Among incident users of a single anticonvulsant, we estimated the rate of ADEs and described the type and severity of ADEs. Results Overall, 12% (n = 2469) of eligible beneficiaries used at least one anticonvulsant in the 2012 to 2014 period (4% [n = 757] incident users, 8% [n = 1712] prevalent users). Incident users were most frequently prescribed gabapentin (n = 461/757, 61%), benzodiazepines (n = 122/757, 16%), and levetiracetam (n = 74/757, 10%); the most common indication was pain relief (n = 214; 28%) followed by epilepsy (n = 53; 7%). Among incident users, the overall ADE rate was 10/100 person-years (95% CI 4-20/100 person-years), of which 29% (n = 28/97) were life threatening (eg, somnolence). Most ADEs among incident monotherapy users were nervous system related (68%, n = 66/97). Conclusion Many older adult community dwelling traditional Medicare beneficiaries had clinically significant ADEs likely attributable to the initiation of anticonvulsant therapy, which was begun for a range of indications.

Organophosphorus (OP) compounds are chemical threat agents and are irreversible inhibitors of the enzyme acetylcholinesterase that lead to a hypercholinergic response that could include status epilepticus (SE). SE particularly targets the heart and the brain and despite existing therapies it is still associated with significant mortality and morbidity. Here, we investigated the effect of intramuscular (i.m.) adjunct therapy consisting of atenolol (AT) and levetiracetam (LV) when administered after paraoxon (POX)-induced SE. The combination therapy was administered twice daily for 2, 7, or 14 days. POX exposure in rats produced rapid SE onset that was treated with atropine, pralidoxime chloride, and midazolam. Here, AT + LV therapy produced significant reductions in POX SE mortality assessed at 30 days post SE. AT + LV therapy exhibited muscle pathology inflammation scores that were not significantly different from saline-treated controls. Pharmacokinetic analyses revealed that the i.m. route achieved faster and stabler plasma therapeutic levels for both AT and LV under OP SE conditions compared with oral administrations. Our data provides evidence of the safety and efficacy of i.m. AT + LV therapy for reducing mortality following POX SE.

Objective: Dravet syndrome is a developmental and epileptic encephalopathy characterized by severe and drug-resistant seizures in early childhood, followed by developmental delay. The purpose of this study was to investigate aspects of pharmacological treatment of Norwegian patients with Dravet syndrome, focusing on the use of antiseizure medicines (ASMs) and identifying treatment challenges. Methods: Patients were identified through medical registries at the National Center for Epilepsy in Norway and National Center for Rare Epilepsy Related Disorders during 2008-2018. Additional clinical data were obtained from medical records and laboratory request forms. Results: We identified 53 patients with Dravet syndrome, 30/23 males/females, aged 2-50 years. The majority of patients with known seizure frequency experienced frequent seizures, 80% (n = 35/44). Only two patients were seizure-free. Valproate (n = 48), clobazam (n = 45), levetiracetam (n = 30), and stiripentol (n = 38) were most commonly used, previous or current use. More than one-third (n = 20) had tried sodium channel blockers (including lamotrigine), but these drugs were used less during the last decade. Polytherapy was common, 81% (n = 43) used two or more ASMs, and eight of these patients used 4-5 drugs (15%). Several challenges were identified: high seizure frequency, comorbidities, treatment changes with a wide range of ASMs, common use of oral gastro-tubes, extensive polypharmacy, and drug interactions. Significance: The use of ASMs has changed over the last decade, in accordance with updated international recommendations. Various treatment challenges were identified. This vulnerable group of patients needs close follow-up for an optimal treatment outcome. The Norwegian Epilepsy Association provided a research grant to the project.

Limited data exist on the effect of continuous renal replacement therapy (CRRT) methods on anti‐epileptic drug pharmacokinetics (PK). This prospective practice‐based PK study aims to assess the impact of continuous venovenous hemofiltration (CVVH), a modality of CRRT, on levetiracetam PK in critically ill patients and to derive individualized dosing recommendations. Eleven patients receiving oral or intravenous levetiracetam and CVVH in various intensive care units at a large academic medical center were enrolled to investigate the need for dosing adjustments. Prefilter, postfilter, and ultrafiltrate samples were obtained before dosing, after the completion of the infusion or 1‐hour postoral dose, and up to 6 additional time points postinfusion or postoral administration. Patient‐specific blood and ultrafiltrate flow rates and laboratory values were also collected at the time of sampling. The average sieving coefficient (SC) for levetiracetam was 0.89 ± 0.1, indicating high filter efficiency. Six of the 11 patients experienced concentrations outside the reported therapeutic range (12–46 mg/L). The average volume of distribution was 0.73 L/kg. CVVH clearance contributes a major fraction of the total levetiracetam clearance (36–73%) in neurocritically ill patients. The average bias and precision of the estimated vs. observed total clearance value was ~ 10.6% and 21.5%. Major dose determinants were identified to be SC and effluent flow rate. Patients with higher ultrafiltrate rates will have increased drug clearance and, therefore, will require higher doses in order to match exposures seen in patients with normal renal function.

Objective Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are immune-mediated diseases characterized by an extensive loss of the epidermal skin layer, often resulting in death. SJS and TEN are often triggered by certain drugs, including antiepileptic drugs (AEDs). Epilepsy is very difficult to treat and often involves the combination of two or more AEDs. In this study, we quantified not only the risk of SJS or TEN associated with single-AED therapy but also the risk related to concomitant AED treatment using reporting-derived signals. Methods An analysis of the Japanese Adverse Drug Event Report (JADER) database was performed from the first quarter of 2004 to the fourth quarter of 2018. The single-AED signals were evaluated using the proportional reporting ratio (PRR), and the combination therapy signals were evaluated using Ω shrinkage measure and combination risk ratio (CRR). Results SJS signals were associated with 11 AEDs, and TEN signals were related to 12 AEDs. Moreover, the following AED combinations were associated with SJS signals: carbamazepine-lorazepam (Ω025 : 0.33, CRR: 2.18) and fosphenytoin-lorazepam (Ω025 : 0.99, CRR: 39.20). The TEN signals were related to the following combinations: clobazam-gabapentin (Ω025 : 0.35, CRR: 3.14), phenytoin-gabapentin (Ω025 : 0.03, CRR: 2.18), valproic acid-gabapentin (Ω025 : 0.15, CRR: 2.25), clobazam-clonazepam (Ω025 : 0.03, CRR: 2.93), clobazam-valproic acid (Ω025 : 0.29, CRR: 1.55), fosphenytoin-lamotrigine (Ω025 : 0.05, CRR: 7.37), and lacosamide-levetiracetam (Ω025 : 0.74, CRR: 1.85). Significance This study identified two AED combinations that increased the SJS signals and seven combinations that increased the TEN signals. Although AED monotherapies require attention for SJS and TEN, some AED combinations require extra caution.

Background Pentylenetetrazole kindling has long been used for the screening of investigational antiseizure drugs. The presence of lamotrigine, at a very low dose, does not hamper kindling in mice; rather it modifies this epileptogenesis process into drug‐resistant epilepsy. The lamotrigine‐pentylenetetrazole kindled mice show resistance to lamotrigine, phenytoin, and carbamazepine. It may also be possible that other licensed antiseizure drugs, like the mentioned drugs, remain ineffective in this model; therefore, this was the subject of this study. Methods Swiss albino mice were kindled with pentylenetetrazole for 35 days in the presence of either methylcellulose vehicle or lamotrigine (subtherapeutic dose, ie, 5 mg/kg). Vehicle vs lamotrigine‐kindled mice were compared in terms of (a) resistance/response toward nine antiseizure drugs applied as monotherapies and two drug combinations; (b) lamotrigine bioavailability in blood and brain; (c) blood‐brain barrier integrity; and (d) amino acids and monoamines in the cerebral cortex and hippocampus. Results Lamotrigine vs vehicle‐kindled mice are similar (or not significantly different P > .05 from each other) in terms of (a) response toward drug combinations; (b) lamotrigine bioavailability; and (c) blood‐brain barrier integrity except for, significantly (P

Bacteriuria has been associated with abnormal neurological status in humans, particularly the geriatric population. In this report, we review 11 cases (7 dogs and 4 cats) that support an association between bacteriuria and abnormal neurological status in veterinary medicine. The included cases presented with neurological deficits consistent with a diffuse forebrain ± brainstem localisation, in which structural brain disease was excluded with magnetic resonance imaging of the head and cerebrospinal fluid analysis, but in which urine bacteriological culture was positive, and neurological deficits improved or resolved with initiation of antibiosis ± fluid therapy and levetiracetam. While further studies are needed to definitively confirm or refute the link between bacteriuria and a reversible encephalopathy, urine bacteriological culture should be considered in veterinary patients presented with an acute onset forebrain (± brainstem) neuro-anatomical localisation, even in the absence of clinical signs of lower urinary tract inflammation.

Levetiracetam is an antiepileptic drug for the treatment of psychiatric patients. In this study, a selective, straightforward, and rapid online heart-cutting liquid chromatography method was developed for the therapeutic drug monitoring of levetiracetam. This method allows for the determination of levetiracetam in human plasma without complex sample preparation. The mobile phases consisted of 30 mM aq. orthophosphoric acid solution/methanol (70:30) at a flow rate of 1 mL/min for the first system and 10 mM aq. orthophosphoric acid solution/methanol (55:45) at a flow rate of 1 mL/min for the second system. The first separation was carried out on a GL Sciences Intersil ODS-3 column (4.6 mm × 150 mm, 3 µm) and the second separation was carried out on a Restek Ultra PFPP column (4.6 mm × 150 mm, 5 µm). The detection was carried out at 205 nm for both systems. The method was validated for selectivity and linearity, which were in the 6-60 µg/mL range. Intra- and interassay accuracies were

BACKGROUND AND PURPOSE The literature provides contrasting results on the efficacy of levetiracetam (LEV) in multiple sclerosis (MS) patients with cerebellar signs. It was sought to evaluate the efficacy of LEV on upper limb movement in MS patients. METHODS In this multicenter double-blind placebo-controlled crossover study, MS patients with prevalently cerebellar signs were randomly allocated into two groups: LEV followed by placebo (group 1) or placebo followed by LEV (group 2). Clinical assessments were performed by a blinded physician at T0 (day 1), T1 (day 22), T2 (2-week wash-out period, day 35) and T3 (day 56). The primary outcome was dexterity in the arm with greater deficit, assessed by the nine-hole peg test (9HPT). Secondary clinical outcomes included responders on the 9HPT (∆9HPT >20%), tremor activity of the daily living questionnaire and self-defined upper limb impairment, through a numeric rating scale. Kinematic evaluation was performed using a digitizing tablet, providing data on normalized jerk, aiming error and centripetal acceleration. RESULTS Forty-eight subjects (45.2 ± 10.4 years) were randomly allocated into two groups (n = 24 each). 9HPT significantly improved in the LEV phase in both groups (P