ILAE treatment guidelines: evidence-based analysis of antiepileptic drug efficacy and effectiveness as initial monotherapy for epileptic seizures and syndromes

Cost-effectiveness analysis of HLA-B*15:02 screening before treatment of epilepsy in Indonesia

INTRODUCTION

Adverse skin reactions due to drugs such as Stevens Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) occur in 3% of people receiving anti epileptic drugs (AED). Although SJS/TEN has a low incidence, the mortality and morbidity rates are high. Indonesia has not adopted HLA-B*1502 screening prior to administration of carbamazepine (CBZ), although previous studies found a relationship between HLA-B*1502 and SJS/TEN.

METHODS

A hybrid decision tree and Markov model was developed to evaluate three strategies for treating newly diagnosed focal epilepsy: CBZ direct therapy, levetiracetam (LEV) direct therapy, and therapy based on HLA-B*15:02 test results. From a societal perspective, base case and sensitivity analyses were carried out over a lifetime.

RESULTS

Direct administration of CBZ appears to have a slightly lower average cost than the HLA-B*15:02 allele screening strategy. The increase in quality-adjusted life year (QALY) in HLA-B*15:02 screening before treatment related to the cost difference reached 0.519 with an incremental cost-effectiveness ratio (ICER) of around USD 984 per unit of QALY acquisition. Direct treatment of LEV increased treatment costs by almost USD 2000 on average compared to the standard CBZ strategy. The increase in QALY is 0.834 in direct levetiracetam treatment, with an ICER of around USD 2230 for each QALY processing.

CONCLUSION

Calculation of the cost-effectiveness of lifetime epilepsy therapy in this study found that the initial screening strategy with the HLA-B*15:02 test was the most cost-effective.

Pharmacodynamic rationale for the choice of antiseizure medications in the paediatric population

In the landscape of paediatric epilepsy treatment, over 20 anti-seizure medications (ASMs) have gained approval from Drug Regulatory Agencies, each delineating clear indications. However, the complexity of managing drug-resistant epilepsy often necessitates the concurrent use of multiple medications. This therapeutic challenge highlights a notable gap: the absence of standardized guidelines, compelling clinicians to rely on empirical clinical experience when selecting combination therapies. This comprehensive review aims to explore current evidence elucidating the preferential utilization of specific ASMs or their combinations, with a primary emphasis on pharmacodynamic considerations. The fundamental objective underlying rational polytherapy is the strategic combination of medications, harnessing diverse mechanisms of action to optimize efficacy while mitigating shared side effects. Moreover, the intricate interplay between epilepsy and comorbidities partly may influence the treatment selection process. Despite advancements, unresolved queries persist, notably concerning the mechanisms underpinning drug resistance and the paradoxical exacerbation of seizures. By synthesizing existing evidence and addressing pertinent unresolved issues, this review aims to contribute to the evolving landscape of paediatric epilepsy treatment strategies, paving the way for more informed and efficacious therapeutic interventions.

Treatment compliance, treatment patterns, and healthcare utilization in epilepsy patients with first add-on antiepileptic drugs: A nationwide cohort study

Objective

This study aimed to assess the treatment compliance, patterns, healthcare resource utilization (HCRU), and costs of anti-epilepsy drugs (AEDs) as the first add-on therapy in patients with epilepsy.

Methods

We conducted a retrospective population-based cohort study using Korean National Health Insurance claims data from 2016 to 2020. Patients with epilepsy who newly received AED add-on therapy were identified and followed for up to 12 months to evaluate persistence, adherence, treatment patterns, HCRU, and costs.

Results

Among 6,746 patients who initiated AED add-on therapy, 65.5% were persistent on their index AED add-on from the index date until the end of the follow-up period, and the mean persistent time on the index add-on was 307.3 ± 92.3 days. A total of 76.8% patients were adherent, with a medication possession ratio (MPR) ≥80%, and the mean MPR was 88.9 ± 25.4%. Persistence and adherence to the index AED add-on were relatively higher among patients prescribed lamotrigine, levetiracetam, oxcarbazepine, and perampanel than those prescribed carbamazepine, topiramate, or valproate. A total of 41.0% of the patients changed their index AED add-on during the follow-up period. The carbamazepine, topiramate, and valproate groups had higher rates of change than the other AED groups. HCRU and costs tended to be lower in the lamotrigine, levetiracetam, oxcarbazepine, and perampanel groups. Furthermore, perampanel showed the lowest HCRU and costs for all-cause cases as well as the lowest length of stay and outpatient visits for epilepsy-related cases.

Conclusion

In this population-based study, the use of lamotrigine, levetiracetam, oxcarbazepine, or perampanel as the first add-on therapy in patients with epilepsy contributed to better treatment compliance and lower HCRU and costs than that of carbamazepine, topiramate, or valproate.

Drug therapy problems and contributing factors among patients with epilepsy

BACKGROUND

Although antiseizure medications play a crucial role in the management of epilepsy, their benefit can be compromised due to drug-related problems. Drug therapy problems can lead to poor seizure control, reduced quality of life, and increased morbidity and mortality in patients with epilepsy. However, in our setting, there is limited knowledge about drug therapy problems and the factors that contribute to them.

OBJECTIVE

The aim of this study was to investigate the prevalence and contributing factors of drug-therapy problems among patients with epilepsy.

METHODOLOGY

A hospital-based prospective observational study was conducted at the neurologic clinic of Ayder Comprehensive Specialized Hospital, located in the Tigray region of Northern Ethiopia. The study included adult patients diagnosed with epilepsy who had been taking at least one antiseizure medication for a minimum of six months. Data were collected by conducting patient interviews and expert reviews of medical and medication records. Prior to data review and interviews, each patient provided written informed consent. Drug therapy problems were identified and classified using Cipolle's method, followed by a consensus review conducted with a panel of experts. Statistical analysis was performed using a statistical software package; SPSS version 22. Binary logistic regression analysis was conducted to determine the contributing factors of drug therapy problems. Statistical significance was determined at p<0.05.

RESULTS

A study conducted on 250 participants revealed that 55.2% of the patients experienced one or more drug therapy problems. Our analysis identified a total of 282 drug therapy problems, with a mean of 2±0.52 drug therapy problems per patient. The most commonly observed drug therapy problems were dosage too low (30.0%), noncompliance (22%), adverse drug reaction (18%), and unnecessary drug therapy (16.4%). The commonly involved antiseizure medications in these drug therapy problems were phenytoin (22.8%), Valproic acid (20.8%), and Phenobarbital (18.4%). Furthermore, our findings revealed that combination therapy (AOR: 3.92, 95%CI: 1.19-12.97) and uncontrolled seizure (AOR: 108.37, 95%CI: 38.7-303.6) exhibited significant associations with drug therapy problems.

CONCLUSION

Drug therapy problems were prevalent among patients with epilepsy. The use of combination therapy and the presence of uncontrolled seizures were identified as significant indicators of drug therapy problems. Therefore, more emphasis should be given to patients with multiple medications and uncontrolled seizures.

Greater need for treatment optimization in patients with epilepsy initiating adjunctive therapy: Results of a retrospective claims analysis of antiseizure medication drug load in the United States

BACKGROUND

This retrospective, observational study used US claims data to assess changes in antiseizure medication (ASM) drug load for a cohort of patients with epilepsy.

METHODS

Adults (≥18 years) with a diagnosis of epilepsy (ICD-10 code G40.xxx) who started new adjunctive ASM treatment with one of 4 branded (brivaracetam, eslicarbazepine, lacosamide, perampanel) or 4 unbranded (carbamazepine, lamotrigine, levetiracetam, topiramate) ASMs between January 1, 2016 and December 31, 2020 were identified from IBM MarketScan® research databases (primary study population). Patients must have been continuously enrolled 360 days before the start of the new ASM (eligibility period). Follow-up was from the start of new ASM until Day 540 (∼18 months). The primary endpoint was concomitant ASM drug load, which included all ASMs except the new (comparator) ASM. A sensitivity analysis population included adults with epilepsy who were continuously enrolled for ≥ 180 days during at least one calendar year in the study period (2016-2020), whether or not the comparator ASM was new or existing during that period. Total ASM drug load, which included comparator ASM and concomitant ASMs, was assessed in the sensitivity analysis population.

RESULTS

In total, 21,332 patients were included in the primary study population, of which 5767 initiated branded ASMs and 15,565 initiated unbranded ASMs. A total of 392,426 patients were included in the sensitivity analysis population during at least one calendar year 2016-2020. Concomitant ASM drug load increased in the 360 days prior to new ASM start and slightly declined thereafter. Mean concomitant ASM drug load for the primary population was 1.6 (SD 1.8) at new ASM start. Concomitant drug load was higher among those starting branded ASM comparators compared to those starting unbranded comparators. Mean total ASM drug load for patients increased over time and was approximately double for patients exposed to branded ASMs (mean range 2.1 to 2.7) compared to that of patients exposed to any unbranded ASM (mean range 1.0 to 1.3).

CONCLUSION

Concomitant ASM drug load increased prior to addition of new ASM, with higher increases observed among patients starting branded vs unbranded ASMs, followed by slight decreases thereafter. Total drug load increased linearly among all patients. These findings underscore the need for ongoing ASM regimen evaluation and treatment optimization in patients with epilepsy.

Adolescent-Onset Epilepsy: Clinical Features and Predictive Factors for First-Year Seizure Freedom

BACKGROUND

 Teenagers with epilepsy require special attention to ensure a successful treatment journey. Our objective was to delineate the clinical characteristics of adolescent-onset epilepsy (AOE) and investigate the predictive factors influencing first-year seizure freedom.

METHODS

 We retrospectively analyzed the medical records of patients whose first seizure occurred between the ages of 10 and 19 years and who received antiseizure medication (ASM) treatment for at least 12 months.

RESULTS

 A total of 67 patients were included, with an average age of 13.5 ± 2.3 years at the onset of their first seizure. The average follow-up period was 45.2 ± 16.9 months, and comorbid conditions were present in 23 patients (34.3%). The majority of the patient population (83.6%) was affected by generalized epilepsy. The most common epilepsy syndrome was epilepsy with generalized tonic-clonic seizures alone at 70.1% (juvenile myoclonic epilepsy 11.9%, juvenile absence epilepsy 1.5%). Regarding ASM treatment, 31 patients (46.3%) received monotherapy, and 28 (41.8%) received dual therapy. Five patients (7.5%) encountered issues related to medication adherence. First-year seizure freedom was observed in 42 patients (62.7%). In multivariate analysis, a negative family history of epilepsy (odds ratio 12.1, 95% confidence interval 1.27-115.44, p = 0.030) was identified as a strong predictive factor of first-year seizure freedom, along with ASM monotherapy (odds ratio 3.99, 95% confidence interval 1.05-15.21, p = 0.043).

CONCLUSION

 These findings suggest that AOE typically exhibits effective control of seizures. A negative family history of epilepsy and ASM monotherapy emerges as robust predictor of achieving favorable outcomes within the early stage of treatment.

First unprovoked seizures among soldiers recruited to the Israeli Defense Forces during 10 consecutive years: A population-based study

OBJECTIVE

The management of patients after a first unprovoked seizure (FUS) can benefit from stratification of the average 50% risk for further seizures. We characterized subjects with FUSs, out of a large generally healthy homogenous population of soldiers recruited by law to the Israeli Defense Forces, to investigate the role of the type of service, as a trigger burden surrogate, in the risk for additional seizures.

METHODS

Soldiers recruited between 2005 and 2014, who experienced an FUS during their service, were identified from military records. Subjects with a history of epilepsy or lack of documentation of FUS characteristics were excluded from the study. Data on demographics and military service and medical details were extracted for the eligible soldiers.

RESULTS

Of 816 252 newly recruited soldiers, representing 2 138 000 person-years, 346 had an FUS, indicating an incidence rate of 16.2 per 100 000 person-years. The FUS incidence rate was higher in combat versus noncombat male and female soldiers (p < .0001). Most subjects (75.7%) were prescribed antiseizure medications (ASMs), and 29.2% had additional seizures after the FUS. Service in combat units, abnormal magnetic resonance imaging, and being prescribed ASMs were correlated with a lower risk of having multiple seizures (95% confidence interval [CI] = .48-.97, .09-.86, .15-.28, respectively). On multivariate analysis, service in combat units (odds ratio [OR] = .48 for seizure recurrence, 95% CI = .26-.88) and taking medications (OR = .46, 95% CI = .24-.9) independently predicted not having additional seizures.

SIGNIFICANCE

FUS incidence rate was higher in combat soldiers, but they had a twofold lower risk of additional seizures than noncombat soldiers, emphasizing the value of strenuous triggers as negative predictors for developing epilepsy. This suggests a shift in the perception of epilepsy from a "yes or no" condition to a continuous trend of predisposition to seizures, warranting changes in the ways etiologies of epilepsy are weighted and treatments are delivered.

Identification and effective connections of core networks in patients with temporal lobe epilepsy and cognitive impairment: Granger causality analysis and multivariate pattern analysis

OBJECTIVE

This study aimed to explore effective connectivity (EC) of the core networks in cognition impairment associated with temporal lobe epilepsy (CI-TLE) by applying resting state and Granger causality analysis (REST-GCA). The specific brain regions that played a critical role in classification were assessed using multivariate pattern analysis (MVPA).

METHODS

Thirty-two patients with CI-TLE and 29 healthy controls who were matched based on age and gender underwent functional magnetic resonance imaging (fMRI).

RESULTS

REST-GCA revealed that patients with CI-TLE displayed decreased GC values in the following brain areas: from the posterior cingulate cortex (PCC) to the left fusiform gyrus (lFFG) and the right parahippocampal gyrus (rPPG); from the right dorsal prefrontal cortex (rDPFC) to the left superior parietal lobule (lSPL); from the left amygdala (lAG) to the PCC. Inhibitory EC was observed from the rDPFC to the PCC compared to HCs. The GC values increased from the right dorsal prefrontal cingulate cortex (rdACC) to the PCC and from the right dorsal forebrain insula (rDAI) to the right middle temporal gyrus (rMTG) in the CI-TLE patients. MVPA showed that the classification yielded an accuracy of 81.91% (78.12%, specificity =85.71%).

CONCLUSION

Our observations indicated that the abnormal EC between the frontal and parietal regions might be associated with the pathophysiological mechanism of CI-TLE. These results also indicated that EC might be play a role as a potential discriminative pattern to detect CI-TLE in patients.

Seizure Remission and Its Predictors Among Epileptic Patients on Follow-Up at Public Hospitals in Eastern Ethiopia: A Retrospective Cohort Study

Background

Epilepsy is one of the common chronic neurological disorders with varying therapeutic responses. Despite the high prevalence of epilepsy and the significant treatment gaps in developing nations, such as Ethiopia, there is a dearth of data on seizure remission and its predictors in Eastern Ethiopia in particular.

Objective

This study aimed to determine seizure remission and its predictors among epileptic patients on follow-up in Hiwot Fana Specialized University Hospital (HFSUH) and Dilchora Referral Hospital (DCRH), from July 2 to 31, 2021.

Methods

A retrospective cohort study was conducted among 418 newly diagnosed epilepsy patients receiving anti-seizure drugs (ASDs) between July 1, 2014, and July 31, 2019, in two public hospitals in Eastern Ethiopia. Relevant data were collected for all patients with a minimum follow-up period of two years. Data were analyzed using SPSS Version 21. Cox proportional hazards model was performed to identify predictors of seizure remission.

Results

Overall, 252 (60.3%) of the study participants have achieved seizure remission for at least one year. The mean time to achieve seizure remission was 1.9 ± 0.87 years. Regarding the seizure remission pattern, 171 (40.9%) patients achieved early remission, 81 (19.4%) achieved late remission, and 166 (39.7%) achieved no remission. Shorter pre-treatment duration (AHR = 2.36, 95% CI: 1.28-4.37); good adherence to ASDs (AHR = 2.40, 95% CI: 1.33-4.34); and monotherapy (AHR = 0.56, 95% CI: 0.32-0.98) were predictors of seizure remission.

Conclusion

We observed that less than two-thirds of epileptic patients had achieved seizure remission. A shorter pre-treatment duration, good adherence to ASDs, and monotherapy were predictors of seizure remission. Therefore, we recommend the requirement of an integrated effort from different health disciplines that increases patients' adherence to ASDs, promotes early visits to medical facilities, and improves the health-seeking behavior of epileptic patients.

Real-world analysis of retention on cenobamate in patients with epilepsy in the United States

BACKGROUND

This retrospective, observational study used US claims data to assess retention rates on cenobamate compared with four branded antiseizure medications (ASMs) in patients with epilepsy.

METHODS

Adults (≥18 years) with prevalent epilepsy (ICD-10 code G40.xx) and ≥ 1 prescription for cenobamate or any of the newer branded ASMs (brivaracetam, eslicarbazepine, lacosamide, or perampanel) between May 1, 2020 and December 31, 2021 were identified from the HealthVerity Marketplace database. At least 360 days of continuous enrollment was required before and after the index date (Day 1 of initiating cenobamate or branded ASM). Patients were followed until cessation of cenobamate or branded ASM or the end of data collection using Kaplan-Meier methods. Retention was compared between cenobamate and the branded ASMs (both as a group and individually) using Chi-square tests.

RESULTS

In total, 4109 patients were included (195 cenobamate; 3914 branded ASMs). A higher proportion of patients in the cenobamate group compared with the branded ASMs group had concurrent focal and generalized epilepsy (65.6% vs 40.0%) and were on ≥ 3 concomitant ASMs (48.2% vs 12.8%) at the index date. Median time to discontinuation (i.e., the time that half the patients discontinued) was not quite reached after 12 months in the cenobamate group (50.3% of patients remained on cenobamate) and was 7.7 months in the branded ASMs group. Retention was significantly higher with cenobamate vs the branded ASMs group (p = 0.04545) and vs the individual ASMs lacosamide (p = 0.03044) and perampanel (p = 0.01558). Twelve-month retention rates (95% confidence intervals) were 50.3% (43.1%-57.0%) for cenobamate, 40.5% (38.9%-42.0%) for branded ASMs overall, 42.3% (38.6%-46.0%) for brivaracetam, 44.1% (39.2%-49.0%) for eslicarbazepine, 39.9% (38.0%-41.8%) for lacosamide, and 36.8% (31.9%-41.8%) for perampanel.

CONCLUSIONS

In this real-world analysis, retention was significantly higher with cenobamate vs a pooled group of four branded ASMs despite a greater frequency of patients in the cenobamate group having characteristics of more difficult-to-treat epilepsy.

Effect of Lacosamide on Interictal Epileptiform Discharges in Pediatric Patients With Newly Diagnosed Focal Epilepsy

BACKGROUND

The purpose of this study was to determine the efficacy of lacosamide (LCM) on interictal epileptiform discharges (IEDs) and evaluate the relationships between IEDs and seizure outcome in pediatric patients with focal epilepsy.

METHODS

Patient inclusion criteria included (1) newly diagnosed focal epilepsy with unknown etiology; and (2) electroencephalogram recorded twice (before and after starting LCM) under the same conditions. The difference between the highest number of IEDs over five successive minutes (IEDs/5 min) and the location of IEDs was determined. Seizure outcome was evaluated one year after achieving the maintenance dose of LCM. Responders were identified as showing a ≥50% reduction in the pre-LCM seizure frequency.

RESULTS

Of 22 patients, 10 showed an increase in IEDs/5 min after starting LCM. The median IEDs/5 min before and after starting LCM was not significantly different, at 1.5 (interquartile range: 0, 31.75) and 10.5 (0, 80.5), respectively. No relationship was identified between the difference in IEDs/5 min and seizure outcome. Patients with multiple regional or diffuse IEDs had significantly poorer seizure outcome compared with patients without those IEDs (P = 0.036 and P = 0.039, respectively). Of 10 patients with single regional IEDs, a tendency of IEDs to disappear was observed between patients with frontal and non-frontal IEDs.

CONCLUSION

The effects of LCM on the number of IEDs may be unrelated to seizure outcome. LCM may be ineffective at improving seizure outcomes in patients with multiple regional or diffuse IEDs.

The impact of the COVID-19 pandemic on people with epilepsy and epilepsy specialists

OBJECTIVES

During the coronavirus disease 2019 (COVID-19) pandemic, the global population experienced changes in diagnosis and treatment patterns. The aim of this study was to evaluate the influence of the COVID-19 pandemic on people with epilepsy (PWE) and epilepsy specialists in China.

METHODS

We retrospectively evaluated newly diagnosed PWE from January 2018 to January 2022 at Shanxi Bethune Hospital. The clinical characteristics of PWE and the prescription habits of epilepsy specialists were analyzed. We also explored changes in seizure control among PWE as a result of the COVID-19 pandemic and assessed the possible causes.

RESULTS

After excluding 49 PWE who were lost to follow-up, 421 PWE were included in the study. They were divided into a prepandemic group and a pandemic group, with December 2019 as the boundary. By comparing the two groups, we found that the duration between first symptom detection and diagnosis was longer in the pandemic group than in the prepandemic group. Epilepsy specialists preferred prescribing the fast-acting antiepileptic drug levetiracetam (LEV) in the pandemic group. During the COVID-19 pandemic, 49.57% of PWE reported difficulties in accessing their epilepsy healthcare provider, and 26.96% reported that appointments with their providers occurred as usual. A lack of anti-seizure medication (ASM) availability was reported by 32.17% of subjects. An increase in seizure frequency was noted in 25.22% of the PWE during the pandemic. The factors increasing seizure frequency during the pandemic were fear of COVID-19, exacerbation of mental states, sleep deprivation, cancelation of regular medical visits, difficulties accessing epilepsy healthcare providers, and a lack of ASM availability.

CONCLUSION

The COVID-19 pandemic exposed PWE to harmful consequences mainly due to medical shortages and worse life states. During the pandemic, there were delays in the diagnosis of PWE, and doctors' prescription habits changed. We must consider the lessons learned during this period of social restrictions and employ recent technological advances to improve treatment for PWE.

Evaluating the bioequivalence of levetiracetam brand and generic oral tablets available in the Saudi market in vivo

Background

Epilepsy is a common global neurological disorder. About 30% of epileptic patients are managed with anti-epileptic Drugs (AEDs). Since 2000, Levetiracetam (LEV) has been marketed around the world as an AED under the brand name Keppra, and recently more generics are found in the Saudi market as cheaper alternatives. The objective of this study is to evaluate the bioequivalence of LEV brand and generics available in the Saudi market in mice.

Methods

Pharmacokinetics (PK), liver function test, and behavioral studies were conducted for LEV brand and generic in different groups of Blab/c mice.

Results

PK results show a significance difference in PK parameters mostly evidenced with generic 3, then generic 2. The only significant different between Keppra and generic 1 was in T1/2. In addition, Keppra did not significantly increase liver enzymes in comparison to other generics. On the other hand, other generics showed less favorable results in increasing liver enzymes. Keppra reduced the number and intensity of epileptic attacks, had no mortality rate due to epilepsy, and was associated with less sever seizures attacks.

Conclusion

Keppra, the brand form of LEV, has better safety and efficacy profiles in mice compared to 3 generics found in the Saudi market. Therefore, we recommend evaluating the same parameters tested in this study in patients utilizing similar generics and brand to establish the existence of bioequivalence between LEV brand and generics.

Bridging Development and Disruption: Comprehensive Insights into Focal Cortical Dysplasia and Epileptic Management

Focal cortical dysplasia (FCD) is a prominent neurological disorder characterized by disruptions in localized brain cell organization and development. This narrative review delineates the multi-faceted nature of FCD, emphasizing its correlation with drug-resistant epilepsy, predominantly in children and young adults. We explore the historical context of FCD, highlighting its indispensable role in shaping our comprehension of epilepsy and cortical anomalies. The clinical spectrum of FCD is broad, encompassing diverse seizure patterns, cognitive impairments, and associated neuropsychiatric disorders. We underscore the importance of differential diagnosis, with techniques ranging from electroencephalogram (EEG) interpretations to microscopic evaluations, and discuss advanced diagnostic modalities, such as the 3T magnetic resonance imaging (MRI) epilepsy protocols. Therapeutically, while anti-seizure medications are often first-line interventions, surgically refractory cases necessitate more invasive procedures, underscoring the importance of individualized treatment. Furthermore, the review touches upon the prognostic aspects of FCD, highlighting the importance of personalized care regimens, and provides insights into emerging therapeutic avenues, including the potential of the mammalian target of rapamycin (mTOR) pathway. Conclusively, this review accentuates the complex relationship between brain development and epileptogenicity inherent to FCD and underscores the promise of future research in enhancing patient outcomes.

Anticonvulsant effects of cenobamate in chemically and electrically induced seizure models in rodents

Background

Cenobamate is an antiseizure medication used to treat partial-onset (focal) seizures. It is a molecule with one chiral center and a unique dual mechanism of action: enhancement of fast and slow inactivation of sodium channels with preferential inhibition of the persistent current and positive allosteric modulation of GABAA receptor-mediated ion channels.

Aims/Methods

Anticonvulsant effects of cenobamate (YKP3089; R-enantiomer), YKP3090 (S-enantiomer), and YKP1983 (racemate) were evaluated in chemically and electrically induced focal and generalized seizure models in rodents. The Genetic Absence Epilepsy Rat from Strasbourg (GAERS) model examined the effect of cenobamate on spike-wave seizures. Motor coordination was assessed with rotarod tests and minimal motor impairment exams.

Results

Early in development, cenobamate was found to have activity in focal and generalized seizure models in animals and was selected for continued development. Cenobamate prevented seizures in a dose-dependent manner, prevented seizure spread, and increased seizure threshold without potentiating seizure initiation or the development of tolerance to its anticonvulsant effects. In contrast, YKP3090 and YKP1983 were only effective against generalized tonic-clonic seizures. Cenobamate also protected mice from 6 Hz psychomotor-induced seizures. Cenobamate showed significant dose-dependent reductions in the number and cumulative duration of spike-and-wave discharges in the GAERS model.

Discussion

Cenobamate showed efficacy or efficacy signals in all animal models of epilepsy tested with a favorable risk-versus-benefit ratio, supporting its clinical use in the treatment of partial-onset (focal) seizures in adults and warranting further clinical research in generalized seizures and absence seizures.

Continuous theta-burst stimulation in patients with drug-resistant epilepsy: A single-blind placebo-controlled cross-over pilot study

OBJECTIVES

To evaluate the effect of continuous theta-burst stimulation (cTBS) in patients with drug-resistant epilepsy (DRE).

METHODS

Twelve patients with DRE (five with idiopathic generalized and seven with focal epilepsy) were included in this cross-over design study and randomized to either first sham or first active stimulation, each applied for 5 consecutive days. A round coil over the vertex was used in generalized epilepsy or a figure-of-8 coil over the "epileptogenic area" in focal epilepsy. Sham stimulation was given by placing the coil 90° perpendicular to the head. The number of seizures, electroencephalography findings, Quality of Life in Epilepsy Inventory (QOLIE-84), and Symptom Check List (SCL-90) scores evaluated during the 8-12 weeks before and after active and sham stimulations were compared statistically.

RESULTS

Eight patients could complete both active and sham stimulation periods of 5 days and two patients completed active stimulation sessions, without any significant adverse effects. The number of seizures significantly reduced after active cTBS, but not after sham stimulation, when compared with those recorded before the stimulation period. QOLIE scores were increased, but interictal epileptiform discharges and SCL-90 scores showed no difference after cTBS. Active stimulation was stopped in one patient after he experienced an aggravation of myoclonic seizures.

CONCLUSIONS

cTBS seemed to be relatively safe and gave promising results in reducing the frequency of seizures in patients with both generalized and focal DRE. This time-saving technique may ease the introduction of repetitive transcranial magnetic stimulation into the routine practice of busy epilepsy clinics.

Effect of levetiracetam therapy on electrocardiographic parameters

AIM

The purpose of this study was to compare the electrocardiographic parameters before and at the sixth month of treatment of patients diagnosed with epilepsy and who were started on levetiracetam therapy.

METHODS

The files of 30 patients diagnosed with epilepsy and on levetiracetam therapy were examined in this study. Clinical findings, electroencephalography (EEG), cranial magnetic resonance imaging (MRI) and electrocardiography (ECG) data before and at the sixth month of treatment were recorded.

RESULTS

The patients' mean age was 10.93 ± 3.74 (4-17) years; 16 (53.33%) patients were boys. In total, 13 (43.3%) were found to experience focal seizures, and 17 (56.7%) generalized epilepsy-type seizures. Comparison of the ECG parameters (PR interval, QTc, QT interval, and QRS duration) revealed a shortening in the PR interval and QTc values at the sixth month of treatment, although the changes were not statistically significant. No significant differences in terms of gender and epilepsy types were observed between the ECG parameters before treatment and at the sixth month (p > 0.05).

CONCLUSION

In this study, levetiracetam was found to have no effect on ECG parameters.

Should substitution monotherapy or combination therapy be used after failure of the first antiseizure medication? Observations from a 30-year cohort study

OBJECTIVES

To assess the temporal trends in the use of second antiseizure (ASM) regimens and compare the efficacy of substitution monotherapy and combination therapy after failure of initial monotherapy in people with epilepsy.

METHODS

This was a longitudinal observational cohort study conducted at the Epilepsy Unit of the Western Infirmary in Glasgow, Scotland. We included patients who were newly treated for epilepsy with ASMs between July 1982, and October 2012. All patients were followed up for a minimum of 2 years. Seizure freedom was defined as no seizure for at least 1 year on unchanged medication at the last follow up.

RESULTS

During the study period, 498 patients were treated with a second ASM regimen after failure of the initial ASM monotherapy, of whom 346 (69%) were prescribed combination therapy and 152 (31%) were given substitution monotherapy. The proportion of patients receiving second regimen as combination therapy increased during the study period from 46% in first epoch (1985-1994) to 78% in the last (2005-2015) (RR = 1.66, 95% CI: 1.17-2.36, corrected-p = .010). Overall, 21% (104/498) of the patients achieved seizure freedom on the second ASM regimen, which was less than half of the seizure-free rate on the initial ASM monotherapy (45%, p < .001). Patients who received substitution monotherapy had similar seizure-free rate compared with those who received combination therapy (RR = 1.17, 95% CI: 0.81-1.69, p = .41). Individual ASMs used, either alone or in combination, had similar efficacy. However, the subgroup analysis was limited by small sample sizes.

SIGNIFICANCE

The choice of second regimen used based on clinical judgment was not associated with treatment outcome in patients whose initial monotherapy failed due to poor seizure control. Alternative approaches such as machine learning should be explored to aid individualized selection of the second ASM regimen.

Epileptic-network-based prediction and control of seizures in humans

Epilepsy is now conceptualized as a network disease. The epileptic brain network comprises structurally and functionally connected cortical and subcortical brain regions - spanning lobes and hemispheres -, whose connections and dynamics evolve in time. With this concept, focal and generalized seizures as well as other related pathophysiological phenomena are thought to emerge from, spread via, and be terminated by network vertices and edges that also generate and sustain normal, physiological brain dynamics. Research over the last years has advanced concepts and techniques to identify and characterize the evolving epileptic brain network and its constituents on various spatial and temporal scales. Network-based approaches further our understanding of how seizures emerge from the evolving epileptic brain network, and they provide both novel insights into pre-seizure dynamics and important clues for success or failure of measures for network-based seizure control and prevention. In this review, we summarize the current state of knowledge and address several important challenges that would need to be addressed to move network-based prediction and control of seizures closer to clinical translation.

Handling Delayed or Missed Dose of Antiseizure Medications: A Model-Informed Individual Remedial Dosing

BACKGROUND AND OBJECTIVES

Delayed or missed antiseizure medications (ASMs) doses are common during long-term or lifelong antiepilepsy treatment. This study aims to explore optimal individualized remedial dosing regimens for delayed or missed doses of 11 commonly used ASMs.

METHODS

To explore remedial dosing regimens, Monte Carlo simulation was used based on previously identified and published population pharmacokinetic models. Six remedial strategies for delayed or missed doses were investigated. The deviation time outside the individual therapeutic range was used to evaluate each remedial regimen. The influences of patients' demographics, concomitant medication, and scheduled dosing intervals on remedial regimens were assessed. RxODE and Shiny in R were used to perform Monte Carlo simulation and recommend individual remedial regimens.

RESULTS

The recommended remedial regimens were highly correlated with delayed time, scheduled dosing interval, and half-life of the ASM. Moreover, the optimal remedial regimens for pediatric and adult patients were different. The renal function, along with concomitant medication that affects the clearance of the ASM, may also influence the remedial regimens. A web-based dashboard was developed to provide individualized remedial regimens for the delayed or missed dose, and a user-defined module with all parameters that could be defined flexibly by the user was also built.

DISCUSSION

Monte Carlo simulation based on population pharmacokinetic models may provide a rational approach to propose remedial regimens for delayed or missed doses of ASMs in pediatric and adult patients with epilepsy.

Prognostic interictal electroencephalographic biomarkers and models to assess antiseizure medication efficacy for clinical practice: A scoping review

Antiseizure medication (ASM) is the primary treatment for epilepsy. In clinical practice, methods to assess ASM efficacy (predict seizure freedom or seizure reduction), during any phase of the drug treatment lifecycle, are limited. This scoping review identifies and appraises prognostic electroencephalographic (EEG) biomarkers and prognostic models that use EEG features, which are associated with seizure outcomes following ASM initiation, dose adjustment, or withdrawal. We also aim to summarize the population and context in which these biomarkers and models were identified and described, to understand how they could be used in clinical practice. Between January 2021 and October 2022, four databases, references, and citations were systematically searched for ASM studies investigating changes to interictal EEG or prognostic models using EEG features and seizure outcomes. Study bias was appraised using modified Quality in Prognosis Studies criteria. Results were synthesized into a qualitative review. Of 875 studies identified, 93 were included. Biomarkers identified were classed as qualitative (visually identified by wave morphology) or quantitative. Qualitative biomarkers include identifying hypsarrhythmia, centrotemporal spikes, interictal epileptiform discharges (IED), classifying the EEG as normal/abnormal/epileptiform, and photoparoxysmal response. Quantitative biomarkers were statistics applied to IED, high-frequency activity, frequency band power, current source density estimates, pairwise statistical interdependence between EEG channels, and measures of complexity. Prognostic models using EEG features were Cox proportional hazards models and machine learning models. There is promise that some quantitative EEG biomarkers could be used to assess ASM efficacy, but further research is required. There is insufficient evidence to conclude any specific biomarker can be used for a particular population or context to prognosticate ASM efficacy. We identified a potential battery of prognostic EEG biomarkers, which could be combined with prognostic models to assess ASM efficacy. However, many confounders need to be addressed for translation into clinical practice.

Medical and surgical treatment of epilepsy in older adults: A national survey

OBJECTIVE

There are no clinical guidelines dedicated to the treatment of epilepsy in older adults. We investigated physician opinion and practice regarding the treatment of people with epilepsy aged 65 years or older. We also sought to study how our opinion and practice varied between geriatricians, general neurologists, and epilepsy neurologists (i.e., epileptologists).

METHODS

We initially piloted our survey to measure test-retest reliability. Once finalized, we disseminated the survey via two rounds of facsimiles, and then conventional mail, to eligible individuals listed in a national directory of Canadian physicians. We used descriptive statistics such as stacked bar charts and tables to illustrate our findings.

RESULTS

One hundred forty-four physicians (104 general neurologists, 25 geriatricians, and 15 epileptologists) answered our survey in its entirety (overall response rate of 13.2%). Levetiracetam and lamotrigine were the preferred antiseizure medications (ASMs) to treat older adults with epilepsy. Two thirds of epileptologists and almost half of general neurologists would consider prescribing lacosamide in >50% of people aged >65 years; only one geriatrician was of the same opinion. More than 40% of general neurologists and geriatricians erroneously believed that none of the ASMs mentioned in our survey was previously studied in randomized controlled trials specific to the treatment of epilepsy in older adults. Epileptologists were more likely as compared to general neurologists and geriatricians to recommend epilepsy surgery (e.g., 66.6% vs. 22.9%-37.5% among older adults).

SIGNIFICANCE

Therapeutic decisions for older adults with epilepsy are heterogeneous between physician groups and sometimes misalign with available clinical evidence. Our surveyed physicians differed in their approach to ASM choice as well as perception of surgery in older adults with epilepsy. These findings likely reflect the lack of clinical guidelines dedicated to this population and the deficient implementation of best practices.

Nrf2 is predominantly expressed in hippocampal neurons in a rat model of temporal lobe epilepsy

BACKGROUND

Drug resistance is a particular problem in patients with temporal lobe epilepsy, where seizures originate mainly from the hippocampus. Many of these epilepsies are acquired conditions following an insult to the brain such as a prolonged seizure. Such conditions are characterized by pathophysiological mechanisms including massive oxidative stress that synergistically mediate the secondary brain damage, contributing to the development of epilepsy. The transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has emerged in recent years as an attractive therapeutic approach targeting to upregulate the antioxidative defenses in the cell, to ameliorate the oxidative stress-induced damage. Thus, it is important to understand the characteristics of Nrf2 activation during epileptogenesis and epilepsy. Here, we studied the temporal, regional, and cell-type specific expression of Nrf2 in the brain, in a rat model of temporal lobe epilepsy.

RESULTS

Early after status-epilepticus, Nrf2 is mainly activated in the hippocampus and maintained during the whole period of epileptogenesis. Only transient expression of Nrf2 was observed in the cortex. Nevertheless, the expression of several Nrf2 antioxidant target genes was increased within 24 h after status-epilepticus in both the cortex and the hippocampus. We demonstrated that after status-epilepticus in rats, Nrf2 is predominantly expressed in neurons in the CA1 and CA3 regions of the hippocampus, and only astrocytes in the CA1 increase their Nrf2 expression.

CONCLUSIONS

In conclusion, our data identify previously unrecognized spatial and cell-type dependent activation of Nrf2 during epilepsy development, highlighting the need for a time-controlled, and cell-type specific activation of the Nrf2 pathway for mediating anti-oxidant response after brain insult, to modify the development of epilepsy.

Bromovalerylurea modulates GABAA receptor-mediated inhibitory neurotransmission while inducing sleep

Bromovalerylurea (BU), an acyl urea derivative, was originally developed as a hypnotic/sedative. We recently reported that BU at a dose of 50 mg/kg ameliorates sepsis, Parkinson's disease, and traumatic brain injury in Wistar rat models through its anti-inflammatory actions on microglia and macrophages. However, since BU was developed more than 100 years ago, its hypnotic mechanism and characteristics are poorly understood. Herein, we conducted an electroencephalogram (EEG) study and found that BU, when administered at a dose of more than 125 mg/kg but not at a dose of 50 mg/kg in Wistar rats, significantly increased non-rapid eye movement (NREM) sleep duration and dose-dependently decreased rapid eye movement (REM) sleep duration. This characteristic of sleep induced by BU is similar to the effect of compounds such as barbiturate, benzodiazepine, and z-drugs, all of which require γ-aminobutyric acid _A receptors (GABA_AR) for hypnotic/sedative activity. To investigate whether BU could potentiate GABA_Aergic neurotransmission, we conducted a whole-cell patch-clamp recording from pyramidal neurons in rat cortical slices to detect spontaneous GABA_AR-mediated inhibitory postsynaptic currents (IPSCs). We found that BU dose-dependently prolonged IPSCs. Importantly, the prolonged IPSCs were not attenuated by flumazenil, a benzodiazepine receptor antagonist, suggesting that modulation of IPSCs by BU is mediated by different mechanisms from that of benzodiazepine. Taken together, these data elucidate the basic characteristics of the hypnotic effects of BU and suggest that the enhancement of GABA_AR-mediated Cl^- flux may be a possible mechanism that contributes to its hypnotic/sedative activity.

Association between anti-seizure medication and the risk of lower urinary tract infection in patients with epilepsy

PURPOSE

The aim of this retrospective study was to analyze the incidence of lower urinary tract infections (LUTI) and antibiotic prescriptions within 12 months after initial prescription of anti-seizure medication (ASM) between January and December 2020 (index date) and to investigate the association between a broad spectrum of ASMs and the risk of LUTI in patients with epilepsy.

METHODS

This retrospective cohort study included a total of 9186 adult patients (≥18 years) with an initial diagnosis of epilepsy and a prescription of an ASM treated in 1284 general practices in Germany between January 2010 and December 2020 (index date). Six frequently prescribed ASMs with at least 1000 available patients were analyzed. Patients treated with one of six ASMs were matched to each other by propensity scores based on sex, age, and secondary diagnoses. Cox regression models were used to analyze the association between the use of ASM and LUTI risk.

RESULTS

The cumulative LUTI incidence 12 months after the start of therapy was highest in patients treated with pregabalin (16.7%), followed by valproate (11.6%) and gabapentin (10.2%). A similar trend was observed for LUTI with antibiotic prescription (9.2% pregabalin, 6.8% valproate, 6.8% gabapentin). Conditional regression analyses revealed that pregabalin therapy was significantly positively associated with LUTI (HR: 1.76; 95% CI 1.29-2.39) and LUTI-based antibiotic prescription (HR: 2.16; 95% CI 1.43-3.27). Carbamazepine was associated with a significantly lower incidence of LUTI in women (HR: 0.47; 95% CI: 0.30-0.75), but not in men. No significant associations were observed for other ASMs.

CONCLUSION

The present study identifies a significant positive association between ASM and LUTI incidence and antibiotic prescriptions in patients with epilepsy treated with pregabalin, whereas a protective effect was found for carbamazepine in women only. No significant associations were observed for the four remaining ASMs.

Effectiveness of Antiseizure Medication Duotherapies in Patients With Glioma: A Multicenter Observational Cohort Study

BACKGROUND AND OBJECTIVES

About 30% of patients with glioma need an add-on antiseizure medication (ASM) due to uncontrolled seizures on ASM monotherapy. This study aimed to determine whether levetiracetam combined with valproic acid (LEV + VPA), a commonly prescribed duotherapy, is more effective than other duotherapy combinations including either LEV or VPA in patients with glioma.

METHODS

In this multicenter retrospective observational cohort study, treatment failure (i.e., replacement by, addition of, or withdrawal of an ASM) for any reason was the primary outcome. Secondary outcomes included (1) treatment failure due to uncontrolled seizures and (2) treatment failure due to adverse effects. Time to treatment failure was estimated from the moment of ASM duotherapy initiation. Multivariable cause-specific Cox proportional hazard models were estimated to study the association between risk factors and treatment failure. The maximum duration of follow-up was 36 months.

RESULTS

A total of 1,435 patients were treated with first-line monotherapy LEV or VPA, of which 355 patients received ASM duotherapy after they had treatment failure due to uncontrolled seizures on monotherapy. LEV + VPA was prescribed in 66% (236/355) and other ASM duotherapy combinations including LEV or VPA in 34% (119/355) of patients. Patients using other duotherapy vs LEV + VPA had a higher risk of treatment failure for any reason (cause-specific adjusted hazard ratio [aHR] 1.50 [95% CI 1.07-2.12], p = 0.020), due to uncontrolled seizures (cause-specific aHR 1.73 [95% CI 1.10-2.73], p = 0.018), but not due to adverse effects (cause-specific aHR 0.88 [95% CI 0.47-1.67], p = 0.703).

DISCUSSION

This observational cohort study suggests that LEV + VPA has better efficacy than other ASM combinations. Similar toxicities were experienced in the 2 groups.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for patients with glioma with uncontrolled seizures on ASM monotherapy, LEV + VPA has better efficacy than other ASM combinations.

Replacement of Valproic Acid with New Anti-Seizure Medications in Idiopathic Generalized Epilepsy

Background: Little is known regarding the non-inferiority of new anti-seizure medications (ASMs) in terms of replacing valproic acid (VPA) in patients with idiopathic generalized epilepsy (IGE). We hypothesized that replacement of VPA with new ASMs would offer non-inferior or better control of seizure frequency. The purpose of this study was to compare epileptic seizure frequency between the subset of patients with IGE who were on VPA and the subset of patients with IGE who replaced VPA with new ASMs. Methods: Patients with IGE who were on or had been on VPA between January 2016 and March 2022 were divided into a group that replaced VPA with new ASMs (VPA-replace group) and a group that remained on VPA (VPA-continue group). We then compared the groups in terms of seizure frequency and myoclonus. Results: Of the 606 patients on VPA between January 2016 and March 2022, 156 patients with IGE were enrolled to this study (VPA-replace group, n = 68; VPA-continue group, n = 88). The VPA-replace group included significantly more females than the VPA-continue group (p < 0.001). The VPA-replace group also showed significantly higher seizure frequency before replacement (p < 0.001), but not after replacement (p = 0.074). Patients on monotherapy displayed improved seizure frequency with new ASMs (p < 0.001). Among the new ASMs, perampanel (PER) significantly improved seizure frequency (p = 0.002). Forty-two patients in the VPA-replace group who had myoclonus achieved significant improvements (p < 0.001). Among these, patients on PER monotherapy (p < 0.001) or PER + lamotrigine (0.016) showed significantly improved myoclonus scale scores. Conclusions: This study shows the non-inferiority of new ASMs compared to VPA, with better seizure control using new ASMs in subsets of patients with IGE on monotherapy.

Pharmacoeconomics Aspects of Antiepileptic Drugs in Pediatric Patients with Epilepsy

Objective: This study assessed the differentiation of treatment costs with newer and older antiepileptic drugs (AEDs) through its correlation with treatment effectiveness and an adverse event (AE) in pediatric patients with epilepsy (PPE). Methods: PPE on monotherapy of AEDs for the last 6 months were screened for this study. Seizure frequency during the study was compared with that within 6 months before the study. The following parameters were also assessed: quality of life in epilepsy, Pittsburgh Sleep Quality Index, and Liverpool AEs Profile. An incremental cost-effectiveness ratio (ICER) analysis based on the costs of pharmacotherapy was also performed. Results: Out of 80 PPE, 67 completed the study, and 13 PPE were lost after failing to meet the inclusion criteria. A total of 56.71% of PPE were on newer AEDs, and 43.28% were on older AEDs. Newer and older AEDs did not differ significantly in seizure frequency reduction and quality of life parameters, although these were improved significantly during the study period. As per ICER, newer AEDs need an additional EUR 36.82 per unit reduction in seizure frequency. Conclusion: Newer AEDs have comparatively better efficacy, although not significantly better than older AEDs. However, the additional cost per unit improvement is quite high with newer AEDs, necessitating pharmacoeconomic consideration in pediatric epilepsy treatment.

Quantitative EEG-Based Seizure Estimation in Super-Refractory Status Epilepticus

BACKGROUND

The objective of this study was to evaluate the accuracy of seizure burden in patients with super-refractory status epilepticus (SRSE) by using quantitative electroencephalography (qEEG).

METHODS

EEG recordings from 69 patients with SRSE (2009-2019) were reviewed and annotated for seizures by three groups of reviewers: two board-certified neurophysiologists using only raw EEG (gold standard), two neurocritical care providers with substantial experience in qEEG analysis (qEEG experts), and two inexperienced qEEG readers (qEEG novices) using only a qEEG trend panel.

RESULTS

Raw EEG experts identified 35 (51%) patients with seizures, accounting for 2950 seizures (3,126 min). qEEG experts had a sensitivity of 93%, a specificity of 61%, a false positive rate of 6.5 per day, and good agreement (κ = 0.64) between both qEEG experts. qEEG novices had a sensitivity of 98.5%, a specificity of 13%, a false positive rate of 15 per day, and fair agreement (κ = 0.4) between both qEEG novices. Seizure burden was not different between the qEEG experts and the gold standard (3,257 vs. 3,126 min), whereas qEEG novices reported higher burden (6066 vs. 3126 min).

CONCLUSIONS

Both qEEG experts and novices had a high sensitivity but a low specificity for seizure detection in patients with SRSE. qEEG could be a useful tool for qEEG experts to estimate seizure burden in patients with SRSE.

Key Predictors of the Need for a Family-Focused Pediatric Epilepsy Adherence Intervention

OBJECTIVE

Nonadherence to anti-seizure drugs (ASMs) is a significant problem in pediatric epilepsy and is linked to increased morbidity, mortality, clinically unnecessary medication changes, and increased healthcare costs. Family interventions can improve adherence. However, it is challenging to know which families will struggle with nonadherence and require intervention. This study aims to identify specific parent, family, child, and medical factors that predict which families most need family-based adherence interventions.

METHODS

Families enrolled in a randomized clinical trial of a family-based adherence intervention completed measures assessing parent, family, child, and medical factors. Families also used an electronic adherence monitor. Adherence >95% was considered high adherence (not requiring intervention) and <95% was considered suboptimal adherence (requiring intervention). We conducted a stepwise logistic regression to assess demographic, medical, child, family, and parent predictors of membership to the suboptimal adherence group.

RESULTS

Of the 200 families of children with new-onset epilepsy who enrolled, 177 families completed the study. Of these families, 121 (68%) were in the high adherence group and 56 (32%) were in the suboptimal adherence group. Families with lower SES, children of color, lower general family functioning, and more parent distress were more likely to be in the suboptimal adherence group.

SIGNIFICANCE

We identified that parent and family factors, as well as sociodemographic characteristics predicted membership in the suboptimal adherence group. It is critical to find creative and practical solutions to assessing and intervening upon key adherence predictors. These may include streamlined screening for parental distress and family functioning, as well as recognition that families of lower SES and communities of color may be at heightened risk for suboptimal adherence.

LC-MS/MS quantification of levetiracetam, lamotrigine and 10-hydroxycarbazepine in TDM of epileptic patients

BACKGROUND

To minimize drug-related toxicity and monitor dosing regimens, an ultra-sensitive, simple and high-throughput analytical method for therapeutic drug monitoring (TDM) is required.

METHODS

A novel LC-MS/MS bioassay of levetiracetam (LEV), lamotrigi1/ne (LTG) and 10-hydroxycarbazepine (MHD) in human plasma was established. The analytes were separated on a Hypersil GOLD^TM C18 column under a 2.5-min isocratic elution after one-step protein precipitation. MS detection was performed under ESI+ mode fitted with selected reaction monitoring.

RESULTS

The validated ranges were 0.1-20 μg/mL for LTG, 0.3-60 μg/mL for MHD and LEV. The intra- and inter-batches of precision and accuracy was within ±15%. The novel method met all other criteria.

CONCLUSION

This method can be used to monitor drug concentrations and decision-making in epileptic patients.

Antiepileptic drug monotherapy for epilepsy: a network meta-analysis of individual participant data

BACKGROUND

This is an updated version of the original Cochrane Review published in 2017. Epilepsy is a common neurological condition with a worldwide prevalence of around 1%. Approximately 60% to 70% of people with epilepsy will achieve a longer-term remission from seizures, and most achieve that remission shortly after starting antiepileptic drug treatment. Most people with epilepsy are treated with a single antiepileptic drug (monotherapy) and current guidelines from the National Institute for Health and Care Excellence (NICE) in the United Kingdom for adults and children recommend carbamazepine or lamotrigine as first-line treatment for focal onset seizures and sodium valproate for generalised onset seizures; however, a range of other antiepileptic drug (AED) treatments are available, and evidence is needed regarding their comparative effectiveness in order to inform treatment choices.

OBJECTIVES

To compare the time to treatment failure, remission and first seizure of 12 AEDs (carbamazepine, phenytoin, sodium valproate, phenobarbitone, oxcarbazepine, lamotrigine, gabapentin, topiramate, eventrate, zonisamide, eslicarbazepine acetate, lacosamide) currently used as monotherapy in children and adults with focal onset seizures (simple focal, complex focal or secondary generalised) or generalised tonic-clonic seizures with or without other generalised seizure types (absence, myoclonus).

SEARCH METHODS

For the latest update, we searched the following databases on 12 April 2021: the Cochrane Register of Studies (CRS Web), which includes PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP), the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Epilepsy Group Specialised Register and MEDLINE (Ovid, 1946 to April 09, 2021). We handsearched relevant journals and contacted pharmaceutical companies, original trial investigators and experts in the field.

SELECTION CRITERIA

We included randomised controlled trials of a monotherapy design in adults or children with focal onset seizures or generalised onset tonic-clonic seizures (with or without other generalised seizure types).

DATA COLLECTION AND ANALYSIS

This was an individual participant data (IPD) and network meta-analysis (NMA) review. Our primary outcome was 'time to treatment failure', and our secondary outcomes were 'time to achieve 12-month remission', 'time to achieve six-month remission', and 'time to first seizure post-randomisation'. We performed frequentist NMA to combine direct evidence with indirect evidence across the treatment network of 12 drugs. We investigated inconsistency between direct 'pairwise' estimates and NMA results via node splitting. Results are presented as hazard ratios (HRs) with 95% confidence intervals (CIs) and we assessed the certainty of the evidence using the CiNeMA approach, based on the GRADE framework. We have also provided a narrative summary of the most commonly reported adverse events.

MAIN RESULTS

IPD were provided for at least one outcome of this review for 14,789 out of a total of 22,049 eligible participants (67% of total data) from 39 out of the 89 eligible trials (43% of total trials). We could not include IPD from the remaining 50 trials in analysis for a variety of reasons, such as being unable to contact an author or sponsor to request data, data being lost or no longer available, cost and resources required to prepare data being prohibitive, or local authority or country-specific restrictions. No IPD were available from a single trial of eslicarbazepine acetate, so this AED could not be included in the NMA. Network meta-analysis showed high-certainty evidence that for our primary outcome, 'time to treatment failure', for individuals with focal seizures; lamotrigine performs better than most other treatments in terms of treatment failure for any reason and due to adverse events, including the other first-line treatment carbamazepine; HRs (95% CIs) for treatment failure for any reason for lamotrigine versus: eventrate 1.01 (0.88 to 1.20), zonisamide 1.18 (0.96 to 1.44), lacosamide 1.19 (0.90 to 1.58), carbamazepine 1.26 (1.10 to 1.44), oxcarbazepine 1.30 (1.02 to 1.66), sodium valproate 1.35 (1.09 to 1.69), phenytoin 1.44 (1.11 to 1.85), topiramate 1.50 (1.23 to 1.81), gabapentin 1.53 (1.26 to 1.85), phenobarbitone 1.97 (1.45 to 2.67). No significant difference between lamotrigine and eventrate was shown for any treatment failure outcome, and both AEDs seemed to perform better than all other AEDs. For people with generalised onset seizures, evidence was more limited and of moderate certainty; no other treatment performed better than first-line treatment sodium valproate, but there were no differences between sodium valproate, lamotrigine or eventrate in terms of treatment failure; HRs (95% CIs) for treatment failure for any reason for sodium valproate versus: lamotrigine 1.06 (0.81 to 1.37), eventrate 1.13 (0.89 to 1.42), gabapentin 1.13 (0.61 to 2.11), phenytoin 1.17 (0.80 to 1.73), oxcarbazepine 1.24 (0.72 to 2.14), topiramate 1.37 (1.06 to 1.77), carbamazepine 1.52 (1.18 to 1.96), phenobarbitone 2.13 (1.20 to 3.79), lacosamide 2.64 (1.14 to 6.09). Network meta-analysis also showed high-certainty evidence that for secondary remission outcomes, few notable differences were shown for either seizure type; for individuals with focal seizures, carbamazepine performed better than gabapentin (12-month remission) and sodium valproate (six-month remission). No differences between lamotrigine and any AED were shown for individuals with focal seizures, or between sodium valproate and other AEDs for individuals with generalised onset seizures. Network meta-analysis also showed high- to moderate-certainty evidence that, for 'time to first seizure,' in general, the earliest licensed treatments (phenytoin and phenobarbitone) performed better than the other treatments for individuals with focal seizures; phenobarbitone performed better than both first-line treatments carbamazepine and lamotrigine. There were no notable differences between the newer drugs (oxcarbazepine, topiramate, gabapentin, eventrate, zonisamide and lacosamide) for either seizure type. Generally, direct evidence (where available) and network meta-analysis estimates were numerically similar and consistent with confidence intervals of effect sizes overlapping. There was no important indication of inconsistency between direct and network meta-analysis results. The most commonly reported adverse events across all drugs were drowsiness/fatigue, headache or migraine, gastrointestinal disturbances, dizziness/faintness and rash or skin disorders; however, reporting of adverse events was highly variable across AEDs and across studies.

AUTHORS' CONCLUSIONS

High-certainty evidence demonstrates that for people with focal onset seizures, current first-line treatment options carbamazepine and lamotrigine, as well as newer drug eventrate, show the best profile in terms of treatment failure and seizure control as first-line treatments. For people with generalised tonic-clonic seizures (with or without other seizure types), current first-line treatment sodium valproate has the best profile compared to all other treatments, but lamotrigine and eventrate would be the most suitable alternative first-line treatments, particularly for those for whom sodium valproate may not be an appropriate treatment option. Further evidence from randomised controlled trials recruiting individuals with generalised tonic-clonic seizures (with or without other seizure types) is needed.

Evaluating Therapeutic Equivalence of Generic and Original Levetiracetam in Patients with Epilepsy: A Retrospective Study

The brand interchangeability of antiepileptic drugs (AEDs) is a topic of debate, especially regarding their therapeutic equivalence. This study evaluates the efficacy and tolerability of generic levetiracetam compared to the brand-name equivalent in a routine clinical setting. We conducted a retrospective study, examining patients with stable seizure frequency who received generic levetiracetam after the brand-name drug. During the six-month substitution period, changes in seizure frequency, hospitalization due to seizure exacerbation, adverse events, composite outcomes related to adjusting the AED dosage, and switching back to original levetiracetam were analyzed. Seventy-five patients were enrolled; the majority (85.3%) had focal onset seizures, and almost half (49.3%) had refractory epilepsy. Six months after the substitution, the mean seizure frequency per month was not significantly different (3.15 ± 14.47 vs. 2.77 ± 11.41; p = 0.970). In patients with controlled seizures before the change, the seizure frequency increased significantly (0.56 ± 1.83 vs. 0.03 ± 0.16; p = 0.012). Adverse events occurred in six patients. We have observed recurrent seizures or adverse events from 14 days after the transition. The original drug return rates due to recurrent seizures and adverse events were 5.3% and 1.3%, respectively. Generic levetiracetam might not show therapeutic equivalence to the original molecule, especially in patients adequately controlled by the brand-name drug.

Clinical Considerations for Rapid Administration of Undiluted or Minimally Diluted Levetiracetam Bolus Doses

INTRODUCTION

The ability to administer medications via rapid intravenous bolus has the potential to allow for the rapid attainment of therapeutic drug levels and to limit the amount of unnecessary fluid volumes infused. The purpose of this review was to evaluate the efficacy and safety of undiluted or minimally diluted levetiracetam bolus doses.

AREAS COVERED

A total of six pieces of literature were evaluated in this review. Doses up to 4,500 mg of intravenous levetiracetam were found to be both efficacious and safe when administered undiluted or minimally diluted in either a peripheral or central line. Product concentrations of levetiracetam ranged from 50 mg/mL to 100 mg/mL, with volumes ranging from 10-30 mL's. Maintenance doses of up to 1,500 mg twice daily were demonstrated to be both efficacious and safe when administered undiluted or minimally diluted. Injection site pain and agitation were the most commonly reported adverse drug effects.

EXPERT OPINION

Though hospitals and clinicians must be judicious with regard to training and the safety concerns of bolus intravenous push doses, and will need to address numerous logistical concerns, this practice is supported in practice guidelines and should be readily employed.

The importance of drug titration in the management of patients with epilepsy

The variable response to antiseizure medication (ASM) treatment and the numerous drug- and patient-related factors that must be considered when initiating therapy make drug titration to an optimal and tolerable dose an essential component in the pharmacologic treatment of patients with epilepsy. When initiating a new ASM, a "start low, go slow" titration approach is generally recommended and has been shown to reduce the risk of severe idiosyncratic reactions with certain medications and improve tolerability with regard to many frequently occurring central nervous system-related adverse effects (e.g., somnolence, dizziness). Many patients with epilepsy will require medication changes due to lack of efficacy or intolerability of the initial regimen. When this occurs, patients may be switched from one monotherapy to another or receive adjunctive therapy. When transitioning a patient from one ASM to another (referred to as monotherapy conversion or transitional polytherapy), there are several strategies for tapering the baseline ASM depending on the clinical scenario. Regardless of the particular strategy, the goal should be to discontinue the baseline ASM in order to prevent increased toxicity due to drug load. When adding on ASM therapy, flexible titration of the new ASM and adjustment of concomitant ASMs to achieve disease control with the lowest possible drug load (lowest numbers and lowest doses) may help improve tolerability of the add-on therapy. Communication with patients during the initiation of a new therapy may help patients adhere to the titration schedule, allowing them to reach their optimal maintenance dose.

Evaluation of persistence and healthcare utilization in patients treated with anti-seizure medications as add-on therapy: A nationwide cohort study in South Korea

OBJECTIVE

To compare medication adherence and healthcare utilization among patients who were treated with anti-seizure medications (ASMs) as first add-on to monotherapy for epilepsy using the national health insurance claims data.

METHODS

A retrospective observational cohort study was conducted using the Korean National Health Insurance claims data. Patients who received ASM as first add-on to monotherapy during January 2017 to February 2018 were included. The selected patients were followed up for 12 months to evaluate persistence, adherence, and healthcare resource utilization.

RESULTS

In total, 4277 patients who received ASM as first add-on to monotherapy for epilepsy were enrolled. The mean treatment duration of add-on ASM was 296.6 ± 108.6 days during the 1-year follow-up period and 64.3% of the total population were persistent on the add-on ASM at 365 days from the index date. The mean medication possession ratio (MPR) was 90.3 ± 23.7 and the proportion of adherent patients with ≥80% MPR was 79.3%. Lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), and perampanel (PER) groups showed significantly higher persistence and adherence than carbamazepine (CBZ), topiramate (TPM), and valproate (VAL) groups during the 1-year follow-up period. Significant differences in length of stays, total hospitalization cost, outpatient visit cost, and emergency cost were shown between ASM groups and LTG, LEV, OXC, and PER showed relatively low utilization and cost.

CONCLUSIONS

Better adherence was observed in LTG, LEV, OXC, and PER groups than in CBZ, TPM, and VAL groups. Healthcare utilization and related costs showed significant difference between ASM groups.

Developing a Conceptual Disease Model of Patient Experiences and Identifying Patient-Reported Clinical Outcome Assessments for Use in Trials of Treatments for Focal Onset Seizures

PURPOSE

To identify concepts important to understanding the experiences of adults with focal onset seizures (FOS) and evaluate clinical outcome assessments (COAs) for measuring these concepts in clinical trials of treatments for FOS.

METHODS

A search of published qualitative research, clinical trials, and approved product labels for FOS treatments was performed to develop a conceptual disease model (CDM) of patients' experience of living with FOS. Concepts of interest (COI) were selected, and a second literature search was conducted to identify COAs measuring these concepts. Ten COAs were selected and reviewed to document their development process, evidence of measurement properties, and methods for interpreting change scores using criteria proposed in regulatory guidelines for patient-reported outcomes to support label claims.

RESULTS

Concepts identified from the published literature (13 articles, 1 conference abstract), 24 clinical trials, and 8 product labels were included in a novel CDM. Impacts on physical, cognitive, and social and emotional function were chosen as COI for evaluating treatment outcomes for FOS; the additional concept of social support and coping strategies was chosen to understand patients' lived experiences. From 51 unique COAs identified, 10 were selected based on their potential coverage of the COI; some symptom severity and health-related quality of life (HRQoL) COAs covered multiple COI. Of these 10, 8 COAs evaluated impacts/limitations on physical function, 8 measured social and emotional impacts, and 5 assessed social support and coping strategies. While most assessments had gaps in evidence validating their measurement properties, 2 COAs measuring symptom severity and 1 COA measuring HRQoL had evidence confirming their potential utility in clinical trials to support label claims.

CONCLUSION

This research provides insights into the experience of patients with FOS and identifies COAs that measure concepts considered to support endpoints in clinical trials for FOS.

Treatment of Focal-Onset Seizures in Children: Should This Be More Etiology-Driven?

To accelerate the process of licensing antiseizure medication (ASM) in children, extrapolation of efficacy data for focal-onset seizures from adults to children ≥2 or ≥4 years of age is now accepted. We summarized the efficacy evidence from randomized, controlled trials that was used to grant approval for the pediatric indication of focal-onset seizures for the different ASMs available in Europe. Data from high-quality randomized, controlled trials in young children are limited, especially on the use of ASMs in monotherapy. Licensure trials are typically focused on seizure type irrespective of etiology or epilepsy syndrome. We elaborate on the importance of etiology- or syndrome-driven research and treatment, illustrating this with examples of childhood epilepsy syndromes characterized by predominantly focal-onset seizures. Some of these syndromes respond well to standard ASMs used for focal-onset seizures, but others would benefit from a more etiology- or syndrome-driven approach. Advances in molecular genetics and neuroimaging have made it possible to reveal the underlying cause of a child's epilepsy and tailor research and treatment. More high-quality randomized, controlled trials based on etiology or syndrome type are needed, including those assessing effects on cognition and behavior. In addition, study designs such as "N-of-1 trials" could elucidate possible new treatment options in rare epilepsies. Broadening incentives currently in place to stimulate the development and marketing of drugs for rare diseases (applicable to some epilepsy syndromes) to more common pediatric epilepsy types and syndromes might be a means to enable high-quality trials, and ultimately allow more evidence-based treatment in children.

Temporally Targeted Interactions With Pathologic Oscillations as Therapeutical Targets in Epilepsy and Beyond

Self-organized neuronal oscillations rely on precisely orchestrated ensemble activity in reverberating neuronal networks. Chronic, non-malignant disorders of the brain are often coupled to pathological neuronal activity patterns. In addition to the characteristic behavioral symptoms, these disturbances are giving rise to both transient and persistent changes of various brain rhythms. Increasing evidence support the causal role of these "oscillopathies" in the phenotypic emergence of the disease symptoms, identifying neuronal network oscillations as potential therapeutic targets. While the kinetics of pharmacological therapy is not suitable to compensate the disease related fine-scale disturbances of network oscillations, external biophysical modalities (e.g., electrical stimulation) can alter spike timing in a temporally precise manner. These perturbations can warp rhythmic oscillatory patterns via resonance or entrainment. Properly timed phasic stimuli can even switch between the stable states of networks acting as multistable oscillators, substantially changing the emergent oscillatory patterns. Novel transcranial electric stimulation (TES) approaches offer more reliable neuronal control by allowing higher intensities with tolerable side-effect profiles. This precise temporal steerability combined with the non- or minimally invasive nature of these novel TES interventions make them promising therapeutic candidates for functional disorders of the brain. Here we review the key experimental findings and theoretical background concerning various pathological aspects of neuronal network activity leading to the generation of epileptic seizures. The conceptual and practical state of the art of temporally targeted brain stimulation is discussed focusing on the prevention and early termination of epileptic seizures.

Role of clinical pharmacists in epilepsy management at a general hospital in Vietnam: a before-and-after study

Background

Clinical pharmacists have an important role in inter-professional healthcare collaboration for epilepsy management. However, the pharmacy practices of managing epilepsy are still limited in Vietnam, deterring pharmacists from routine adjustments of antiepileptic drugs, which could decrease the patients’ quality of life. This study aimed to assess the effectiveness of pharmacist interventions in epilepsy treatment at a Vietnamese general hospital.

Methods

A before-and-after study was conducted from January 2016 to December 2018. All patients with a diagnosis of epilepsy and being treated at the investigated hospital were recruited and screened for eligibility and exclusion criteria. The primary outcome was the proportion of patients in good control of their epilepsy (with two seizures or less in a year). The secondary outcome was the number of patients maintaining optimized concentrations within the therapeutic range of carbamazepine (4–12 mg/L), phenytoin (10–20 mg/L), or valproic acid (50–100 mg/L). Collected data were analyzed using two proportions Z-test or Chi-square test.

Results

A total of 141 participants were enrolled in the study. While most patients were given lower prescribed daily doses than the recommendations from the World Health Organization, over 56% of the participants still experienced adverse drug effects. More than half of the patients received at least one pharmacists’ intervention, which increased by 25.0% the effectiveness of the therapy (p < 0.001) and by 14.6% the number of patients with optimized drug concentrations (p = 0.018).

Conclusion

Epilepsy management requires a multiple-stepped and comprehensive approach, with a focus on the health and safety of the patients. As part of the healthcare team, pharmacists need to engage at every stage to monitor the patient’s response and determine the most effective treatment with the fewest adverse drug reactions.

Trial registration ClinicalTrials.gov, NCT04967326. Registered July 19, 2021—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04967326

Prognostic implications of persistent interictal epileptiform discharges on antiseizure medication withdrawal in patients with epilepsy in five-year remission

PURPOSE

Whether patients with epilepsy in long-term remission and interictal epileptiform discharges (IEDs) can stop antiseizure medication (ASM) remains a challenging topic even though multiple studies have investigated ASM withdrawal. This study aimed to estimate seizure relapse and its risk factors in patients with epilepsy in five-year remission and persistent IEDs.

METHODS

Patients with epilepsy and persistent IEDs were prospectively recruited from the Affiliated Nanjing Brain Hospital of Nanjing Medical University from Dec.1, 2010 to Dec.30, 2019. All enrolled patients achieved seizure remission for over five years and were divided into the ASM withdrawal and continuous treatment groups according to their personal preference. Seizure outcomes and 24 h video electroencephalogram findings were obtained through clinical visits or telephone interviews every three months until March 31, 2021. The cumulative recurrence rate and its diversity between the ASM withdrawal and continuous treatment groups were tested using Kaplan-Meier analysis. Multivariate Cox regression analysis was performed to explore the independent predictors for seizure recurrence. Relapsed patients were further monitored for their seizure control and prognosis.

RESULTS

A total of 83 patients with epilepsy in five-year remission and persistent IEDs were enrolled in this study, including 41 (49.4%) in the ASM withdrawal group and 42 (50.6%) in the continuous ASM treatment group. During the follow-up with a median time of 36.8 months (range from 18.7 to 104.6 months), the seizure relapse in off-medication patients (43.9%, 18/41) was higher than that in on-medication patients (21.4%, 9/42; P = 0.031). In the multivariate analysis model, independent predictors for seizure recurrence were structural-metabolic epilepsy or unknown cause (HR = 6.185, 95% CI 1.166-32.805) and multiple seizure types (HR = 2.807, 95% CI 1.051-7.502). ASM withdrawal was not found to be an independent risk factor for seizure recurrence. Of 27 patients with seizure recurrence, 25 were given reinstitution or continuous ASM therapy, whereas two chose sustained observation without medication. At the end of the follow-up, 70.4% (19/27) of recurrence patients were completely free from seizures for at least one year again, and only one patient developed refractory epilepsy.

CONCLUSION

For patients with epilepsy in five-year remission and persistent IEDs, drug withdrawal may be a rational choice after the individualized assessment of benefits and risks. Furthermore, the independent risk factors for the seizure relapse were structural-metabolic epilepsy or an unknown cause, and multiple seizure types. Finally, patients with epilepsy relapsing after ASM withdrawal could achieve seizure remission again after ASM retreatment.

Epilepsy Treatment Complacency in Patients, Caregivers, and Health Care Professionals

Objective

To explore the perspectives of adult patients with epilepsy, caregivers, and health care professionals (HCPs) on treatment for seizures and treatment decisions, we developed and administered the STEP Survey (Seize the Truth of Epilepsy Perceptions).

Methods

Participants were recruited from online panel M3 and by Rare Patient Voice and completed the self-administered online STEP Survey. Analysis of variance and chi-square tests were used for group comparisons.

Results

The STEP Survey was completed by 400 adult patients, 201 caregivers, and 258 HCPs. Patients estimated reporting 45% of their seizures to their HCP, whereas caregivers estimated 83% and HCPs estimated 73% were reported. The most common reason for not reporting seizures was that the seizures were not serious enough to mention (patients 57%; caregivers 66%). A minority of patients (25%) and caregivers (30%) were very or extremely likely to ask their HCP about changing antiseizure medication (ASM) in the next 12 months. The HCP was most frequently selected by patients, caregivers, and HCPs as the person who initiates discussion of changing ASMs (patients 73%/caregivers 66%/HCPs 75%) and increasing ASM dosage (patients 77%/caregivers 68%/HCPs 81%). A majority of patients (65%) and caregivers (68%) somewhat or strongly agreed that they do not change ASMs due to fear of getting worse. HCPs perceive this fear less often, stating that 50% of their patients feel afraid when a second ASM was added.

Conclusions

Improved reporting of all seizures, discussion of treatment changes, and the impact of fear on treatment decisions provide opportunities to reduce complacency and optimize patient outcomes.

Relevant pharmacological interactions between alkylating agents and antiepileptic drugs: Preclinical and clinical data

Seizures are relatively common in cancer patients, and co-administration of chemotherapeutic and antiepileptic drugs (AEDs) is highly probable and necessary in many cases. Nonetheless, clinically relevant interactions between chemotherapeutic drugs and AEDs are rarely summarized and pharmacologically described. These interactions can cause insufficient tumor and seizure control or lead to unforeseen toxicity. This review focused on pharmacokinetic and pharmacodynamic interactions between alkylating agents and AEDs, helping readers to make a rational choice of treatment optimization, and thus improving patients' quality of life. As an example, phenobarbital, phenytoin, and carbamazepine, by increasing the hepatic metabolism of cyclophosphamide, ifosfamide and busulfan, yield smaller peak concentrations and a reduced area under the plasma concentration-time curve (AUC) of the prodrugs; alongside, the maximum concentration and AUC of their active products were increased with the possible onset of severe adverse drug reactions. On the other side, valproic acid, acting as histone deacetylase inhibitor, showed synergistic effects with temozolomide when tested in glioblastoma. The present review is aimed at providing evidence that may offer useful suggestions for rational pharmacological strategies in patients with seizures symptoms undertaking alkylating agents. Firstly, clinicians should avoid the use of enzyme-inducing AEDs in combination with alkylating agents and prefer the use of AEDs, such as levetiracetam, that have a low or no impact on hepatic metabolism. Secondly, a careful therapeutic drug monitoring of both alkylating agents and AEDs (and their active metabolites) is necessary to maintain therapeutic ranges and to avoid serious adverse reactions.

Childhood absence epilepsy: Electro-clinical manifestations, treatment options, and outcome in a tertiary educational center

Purpose and Background

To evaluate the electro-clinical manifestations and outcomes of children with absence epilepsy at a tertiary center in Saudi Arabia.

Methods

This retrospective study reviewed the medical and EEG records of patients who were diagnosed to have CAE as per the International League Against Epilepsy (ILAE) definition for CAE. The study was conducted in the pediatric neurology clinic of King Khalid University Hospital, King Saud University Medical City, Riyadh, Saudi Arabia, between January 2000 and December 2019. Patients who did not meet (ILAE) criteria, lost follow-up, and those who did not receive treatment at KKUH were excluded. Data regarding the patient's disease, electro-clinical manifestations, anti-seizure medication response, and outcomes were collected.

Results

A total of 35 patients, with an average age at diagnosis of 7 ± 2.1 y, were included in the study; among them, 51.4% were female and approximately 48.6% presented with a family history of epilepsy. Regarding clinical features, all patients experienced staring and altered awareness, 94.2% had less than 20 spells per day at the time of diagnosis, and 65.7% were provoked by the hyperventilation test. Regarding EEG findings, all patients had bilateral, symmetrical, and synchronous discharges in the form of regular 3 Hz spike-and-wave complexes, and 94.3% had a generalized initial ictal discharge. Also, 22.8% had eye fluttering with electrographic seizures. Ethosuximide (ESM) was used as the drug of choice in 45.7% of the patients. Regarding clinical outcomes, 94.3% had their disease clinically controlled, and 80% had a normalized EEG after few months of starting anti-seizure medication. Finally, 37.2% experienced complete remission of epilepsy after 3–5 y; however, one patient developed juvenile myoclonic epilepsy.

Conclusion

This study described the electro-clinical manifestations of patients with childhood absence epilepsy and outcomes. Furthermore, early diagnosis and prompt treatment of childhood absence epilepsy improve treatment outcomes.

Experience of perampanel monotherapy beyond initial titration to achieve seizure freedom in patients with focal-onset seizures with newly diagnosed or currently untreated recurrent epilepsy: A post hoc analysis of the open-label Study 342 (FREEDOM)

Objective

This post hoc analysis evaluated whether continued treatment with perampanel monotherapy beyond initial titration may be appropriate for patients with focal‐onset seizures (FOS) with currently untreated epilepsy to achieve seizure freedom with an effective dose.

Methods

Study 342 (NCT03201900; FREEDOM) is a single‐arm, open‐label, Phase III study of perampanel monotherapy. Patients aged ≥12 years with untreated FOS received perampanel 4 mg/d in a 32‐week Treatment Phase (6‐week Titration and 26‐week Maintenance Periods); in case of seizure(s) during Maintenance Period, patients could enter a 30‐week Treatment Phase (4‐week Titration and 26‐week Maintenance Periods) to be up‐titrated to perampanel 8 mg/d. The primary endpoint was seizure‐freedom rate during Maintenance Period in the modified Intent‐to‐Treat (mITT) Analysis Set (patients who had ≥1 post‐dose efficacy measurement during Maintenance Period); safety was monitored. This analysis of 4‐mg/d efficacy data assessed the proportion of patients achieving seizure freedom during the Maintenance Period (responders) relative to patients with an early/later response (depending on seizure status during the Titration Period).

Results

In the mITT population (n = 73), 46 patients were 4‐mg/d responders; of whom, 37 (80.4%) were early responders and nine (19.6%) were later responders. The mean (standard deviation) percent reductions in FOS frequency from baseline at the end of the 4‐mg/d Titration Period were 100.0% (0.0%; early responders) and 46.3% (97.3%; later responders). Among the 27 4‐mg/d nonresponders, nine (33.3%) patients who had an early response experienced seizure(s) during the subsequent 4‐mg/d Maintenance Period. Safety outcomes were similar, regardless of responder status, without new safety concerns.

Significance

Some patients with untreated FOS may benefit from continued treatment beyond initial titration of perampanel monotherapy to achieve seizure freedom, suggesting that it may not be appropriate to make treatment decisions to discontinue or switch from perampanel monotherapy solely based on seizure response before an effective dose has been reached.

Dravet syndrome: A quick transition guide for the adult neurologist

INTRODUCTION

Dravet syndrome (DS) is still seen as a "pediatric disease", where patients receive excellent care in pediatric centers, but care is less than optimal in adult health care systems (HCS). This creates a barrier when young adults need to leave the family-centered pediatric system and enter the adult, patient-centered HCS. Here we create a guide to help with the transition from pediatric to adult for patients with DS.

METHODS

Experts in Dravet syndrome flagged the main barriers in caring for adults with DS and created a 2-page transition summary guide based on their expertise and a literature review.

RESULTS

The 2-page guide addresses: DS diagnosis in children and adults; clinical manifestations, including the differences in seizures types and frequencies between children and adults with DS; the natural history of intellectual disability, behavior, gait, motor disorders and dysautonomia; a review of optimal treatments (including medications not commonly used in adult epilepsy settings such as stiripentol and fenfluramine), as well as emergency seizure management; avoidance of triggers, preventive measures, and vaccine administration in adults with DS.

CONCLUSION

Several young adults with DS are still followed by their child neurologist. This 2-page transition guide should help facilitate the transition of patients with DS to the adult HCS and should be given to families as well as adult health care providers that may not be familiar with DS.

Efficacy and tolerability of antiseizure drugs

Drug-resistant epilepsy occurs in 25-30% of patients. Furthermore, treatment with a first-generation antiseizure drug (ASD) fails in 30-40% of individuals because of their intolerable adverse effects. Over the past three decades, 20 newer- (second- and third-)generation ASDs with unique mechanisms of action and pharmacokinetic profiles have been introduced into clinical practice. This advent has expanded the therapeutic armamentarium of epilepsy and broadens the choices of ASDs to match the individual patient's characteristics. In recent years, research has been focused on defining the ASD of choice for different seizure types. In 2017, the International League Against Epilepsy published a new classification for seizure types and epilepsy syndrome. This classification has been of paramount importance to accurately classify the patient's seizure type(s) and prescribe the ASD that is appropriate. A year later, the American Academy of Neurology published a new guideline for ASD selection in adult and pediatric patients with new-onset and treatment-resistant epilepsy. The guideline primarily relied on studies that compare the first-generation and second-generation ASDs, with limited data for the efficacy of third-generation drugs. While researchers have been called for investigating those drugs in future research, epilepsy specialists may wish to share their personal experiences to support the treatment guidelines. Given the rapid advances in the development of ASDs in recent years and the continuous updates in definitions, classifications, and treatment guidelines for seizure types and epilepsy syndromes, this review aims to present a complete overview of the current state of the literature about the efficacy and tolerability of ASDs and provide guidance to clinicians about selecting appropriate ASDs for initial treatment of epilepsy according to different seizure types and epilepsy syndromes based on the current literature and recent US and UK practical guidelines.

Neuropharmacology of Antiseizure Drugs

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.

Retention of antiseizure medications for epilepsy in multiple sclerosis: A retrospective observational study

PURPOSE

Epilepsy in multiple sclerosis (MS) is rare, and longitudinal clinical studies evaluating treatment with antiseizure medications (ASMs) are difficult to conduct. We instead designed a nationwide register study to estimate retention rates of ASMs prescribed as initial monotherapy for epilepsy in MS and investigated factors influencing their retention.

METHODS

multiple sclerosis patients with a first prescription of ASM for epilepsy were identified by cross-referencing the Swedish MS register with comprehensive national registers. One and five-year retention rates of ASMs were estimated using Kaplan-Meier analysis. Cox proportional regression was employed to estimate hazard ratios (HR) of discontinuation for different ASMs as well as for baseline predictors.

RESULTS

One hundred and twenty-nine MS patients were included. The most commonly prescribed ASMs were: carbamazepine (n = 38, 29.5%), lamotrigine (n = 33, 25.6%) and levetiracetam (n = 19, 14.7%). One-year retention rates (95% CI) were: lamotrigine 87.5% [76, 98.9], carbamazepine 60.5% [45, 76], levetiracetam 60.2% [37.2, 83.2], valproate 51.3% [23, 79.6] and phenytoin 44.4% [11.8, 77]. Fiveyear retention rates (95% CI) were: lamotrigine 74.4% [57.3, 91.5], carbamazepine 52.2% [34.9, 69.4], valproate 51.3% [23.1, 79.5] and phenytoin 14.8% [0, 40.9]. With carbamazepine as reference, lamotrigine was the only ASM that displayed a lower hazard of discontinuation, HR 0.41 [0.17, 0.99]. We could not identify any baseline factors that influenced the risk of discontinuation.

CONCLUSION

Lamotrigine displayed the lowest risk of discontinuation when prescribed as initial monotherapy for epilepsy in MS. Newer ASMs generally compared well to older ones, at least suggesting non-inferiority.

Etiology-specific response to antiseizure medication in focal epilepsy

OBJECTIVE

In focal epilepsy, data on the etiology-specific response to antiseizure medication (ASM) are surprisingly sparse. In this study, we sought to reappraise whether seizure outcome of pharmacological treatment is linked to the underlying etiology. Furthermore, we assessed ASM load with respect to the cause of epilepsy.

METHODS

Data were retrospectively obtained from the electronic database of the three sites of an academic adult epilepsy outpatient clinic. For each patient, presumed cause of epilepsy was categorized into one of nine etiological groups. Individual drug loads were calculated according to the 2020 World Health Organization Center for Drug Statistics Methodology ATC/DDD Index. Univariate and multivariate analyses were conducted to explore the association between different etiologies and outcome regarding 12-month seizure freedom as well as ASM load.

RESULTS

A total of 591 patients with focal epilepsy were included in the final analysis. Ischemic stroke was the etiology with the highest rate of 12-month terminal seizure freedom (71.2%, 95% confidence interval [CI] = 57.9-82.2) and, considering all etiological groups, was an independent predictor of seizure freedom (odds ratio = 2.093, 95% CI = 1.039-4.216). The lowest rates of seizure freedom were observed in patients with hippocampal sclerosis (28.2%, 95% CI = 15.0-44.9) and malformation of cortical development (16.7%, 95% CI = 2.1-48.4). In patients with ischemic stroke, median ASM load (1.0, interquartile range [IQR] = .5-1.8) was significantly lower compared to that in patients with hippocampal sclerosis (median = 1.8, IQR = 1.2-3.0, p = .008) and brain tumors (median = 1.7, IQR = .7-3.2, p = .049).

SIGNIFICANCE

Response to treatment with ASM is highly etiology-specific and best in patients with epilepsy due to ischemic stroke. Interestingly, this most favorable treatment outcome can be achieved by the lowest ASM load considering all etiological groups. In focal epilepsy, etiology should be taken into account when counseling patients about their expected seizure outcome with pharmacological treatment and when tailoring initial ASM doses.