The New Antiepileptic Drugs: Their Neuropharmacology and Clinical Indications

The Prevalence of Seizures in Brain Metastasis Patients on Anticonvulsant Prophylaxis: A Systematic Review and Meta-Analysis

BACKGROUND

Brain metastasis (BM) prognosis is incredibly poor and is often associated with considerable morbidity. Seizures are commonly present in these patients, and their biopsychosocial impact can be dangerous. The use of antiepileptic drugs (AEDs) as primary prophylaxis remains controversial. This systematic review and meta-analysis aim to evaluate the efficacy of AED prophylaxis in patients with BM.

METHODS

MEDLINE via PubMed, Web of Science, EMBASE, and Cochrane were searched for articles pertinent to AED prophylaxis use in patients with BM. Patients with BM previously treated for cancer who were seizure naive at the time of inclusion were included. Data regarding patient characteristics, type of AED, prior treatments, and groups at a high risk of seizure were extracted. Seizure prevalence was obtained.

RESULTS

Eight studies were included in this systematic review and meta-analysis; 1902 total patients with BM were included, with 381 receiving antiepileptic prophylaxis, and 1521 receiving no prophylaxis. Although the odds of a seizure in the treatment group was found to be 1.158 times the odds of a seizure in the control group, the odds ratio was not statistically significant (t-statistic = 0.62, P value = 0.5543).

CONCLUSIONS

There was no significant difference in the odds of seizure development in control groups compared to patients receiving prophylactic antiepileptic therapy. As patients with BM present with heterogeneity in tumor characteristics and receive various treatment modalities, future research is needed to identify groups that may benefit more significantly from AED prophylaxis.

Comparing patient reported and medical record data of adverse drug reactions to anti-seizure drugs

BACKGROUND

Anti-seizure drugs (ASDs) can potentially cause serious adverse drug reactions (ADRs). Patient self-reporting can increase the rate of ADR detection, but studies examining patient self-reporting of ADRs caused by ASDs are lacking.

AIM

To determine the characteristics of ADRs reported by patients receiving ASDs, assess laboratory data and medical record confirmation of patient-reported ADRs, and explore factors associated with laboratory data and medical record confirmation.

METHOD

A self-reporting questionnaire was distributed to patients prescribed ASDs at outpatient clinics. Patients assessed the causality of suspected ADRs using Causality Assessment Tool. Naranjo's algorithm was used by researchers for causality assessment. Medical records were used to gather information on ADR symptoms, ASD medication, and abnormal laboratory data.

RESULTS

From 478 distributed questionnaires, 93.1% completed the questionnaire and 67.4% of respondents reported at least one ADR. The most common ADRs were drowsiness (50.7%), dizziness (9.7%), and ataxia (4.3%). For causality, suspected ADRs were classified as possible in 52.3% of cases and probable in 46.3% of cases by patients, and possible in 64.7% of cases and probable in 25.7% of cases by researchers. Only 12.7% of patients had laboratory data and/or medical record confirmation of suspected ADRs. The psychiatry clinic was less likely to confirm suspected ADRs compared to the epilepsy clinic (OR = 0.412, p = 0.022).

CONCLUSION

Confirmation of patient-reported ADRs with either laboratory data or medical records was uncommon. Recording patient-reported ADRs in patients' medical history and monitoring laboratory tests related to patient-reported symptoms should be promoted to increase the safety of ASD treatment.

Trends and Differences in Status Epilepticus Treatment of Children and Adults Over 10 Years: A Comparative Study of Medical Records (2012-2021) from a University Hospital in Germany

BACKGROUND AND OBJECTIVES

Over the last decade, significant advancements have been made in status epilepticus (SE) management, influenced by landmark trials such as ESETT and RAMPART. The objectives of this study were to explore the evolution of drug treatments for patients with SE, to investigate its association with outcomes and mortality, and to evaluate differences in treatment patterns between adults and children for a potential shift in medication trends due to the above mentioned trials.

METHODS

The medical records of patients with SE treated at University Hospital Frankfurt between 2012 and 2021 were evaluated for medication trends and outcomes. Children and adults were analyzed separately and jointly.

RESULTS

This study included 1151 SE episodes in 1021 patients (mean age = 53.3 ± 28.3 years; 52.5 % female [n = 533]). The overall percentage of patients with SE treated prehospital was stable over the last decade. More than half (53.6 %) of children were treated prehospital, compared with less than one-third (26.7 %) of adults. Prehospital midazolam use increased over time, while diazepam use decreased. Lorazepam was the most commonly used benzodiazepine in hospitals in 2012-2013, used in 40.8 % of all episodes. However, its use declined to 27.2 % in 2020-2021, while midazolam use increased to 44.0 %. While the use of older antiseizure medications (ASMs) such as phenobarbital (p = 0.02), phenytoin (p < 0.001), and valproate (p < 0.001) decreased, the use of newer ASMs such as levetiracetam and lacosamide significantly increased (p < 0.001). Propofol and continuous midazolam infusion remained the most used third-line therapy drugs. Overall mortality was 16.5 % at discharge and 18.9 % at 30 days. Mortality rates did not change between 2012 and 2021.

CONCLUSION

Midazolam has become the preferred benzodiazepine in pre- and in-hospital settings, both in children and adults. The same applies to the increased use of levetiracetam and lacosamide over time in children and adults, while phenobarbital, phenytoin, and valproate use decreased. Continuous midazolam infusion and propofol remain the most frequently used anesthetic drugs. Mortality and outcome remain stable despite changes in medication patterns.

Teratogenic impacts of Antiepileptic drugs on development, behavior and reproduction in Drosophila melanogaster

Clobazam (CLB) and Vigabatrin (VGB) are the two widely used Antiepileptic drugs, which may have teratogenic potentiality and it has been evaluated in the fruit fly Drosophila melanogaster. These different concentrations of CLB (0.156, 0.25, and 0.312 μg/ml) and VGB (17.6, 22, and 44 μg/ml) were used to evaluate the life-history parameters, developmental, and behavioral abnormalities. The results revealed that life-history parameters (fecundity, fertility, larval and pupal mortality) were significantly affected along with varied developmental duration, and pupal and adult deformities in flies on exposure of CLB and VGB in concentration dependent manner. The present study demonstrated that the prenatal treatment of CLB and VGB has displayed clear teratogenic potentiality with various deformities in the fruit fly. The findings could be correlated with the various abnormalities in human caused by the use of AEDs.

Design and validation of a predictive equation to estimate unbound valproic acid concentration

OBJECTIVES

Total plasma levels of valproic acid (VPA) may mask an increased risk of adverse effects in hypoalbuminaemic patients since, in these patients, the free fraction is higher. The aim of this study is to analyse the relationship between plasma levels of total and free VPA (FVPA) in hypoalbuminaemic patients and define an equation that allows the estimation of FVPA concentration, as well as to validate the obtained equation.

METHODS

This is a retrospective observational study conducted between January 2015 and January 2020. Hypoalbuminaemic adult patients with normal renal function were included. Serum VPA levels were determined using an automated enzyme immunoassay technique with a pre-treatment of the sample by ultrafiltration for the quantification of FVPA. Patients' determinations were randomised into two groups: first, to calculate the FVPA estimation equation (regression group) by multiple linear regression analysis; and second to validate the equation (validation group), calculating the agreement between experimental and estimated FVPA concentrations using Lin's coefficient and a Bland and Altman analysis.

RESULTS

We included 51 determinations, corresponding to 33 patients: 26 in the regression group, and 25 in the validation group. The multiple linear regression analysis showed a statistically significant relationship between FVPA concentration (Y), total VPA concentration (X1) and albumin level (X2), explained by the equation Y=11.882 + 0.216*X1-4.722*X2. Pearson's correlation coefficient was 0.798 (p<0.001). Lin's coefficient was 0.82 (95% CI 0.63 to 0.92). The Bland and Altman analysis showed a bias of 0.32 mg/L, and the concordance limits were between -3.80 and 4.44.

CONCLUSIONS

The calculated equation adequately predicts FVPA concentration, with a high degree of correlation between the variables. Despite Lin's coefficient outcome, Bland and Altman analysis showed a minimum bias that slightly underestimates FVPA concentration, positioning the calculated equation as a useful and validated estimation tool in hypoalbuminaemic patients with normal renal function.

Developmental Toxicity Study of DL-4-Hydroxy-4-Phenylhexanamide (DL-HEPB) in Rats

Antiepileptic drugs affect embryonic development when administered during pregnancy, generating severe alterations, such as as cleft lip, spina bifida, heart abnormalities, or neuronal alterations. The compound DL-4-hydroxy-4-phenylhexanamide (DL-HEPB), a phenyl alcohol amide structurally different from known anticonvulsants, has shown good anticonvulsant effects in previous studies. However, its effects on intrauterine development are unknown. So, the purpose of this study was to determine the potential of DL-HEPB to produce alterations in conceptus. Pregnant Wistar rats were orally exposed to 0, 50, 100, and 200 mg/kg of DL-HEPB during organogenesis, and their food consumption and weight gain were measured. On gestation day 21, pregnant females were euthanized to analyze the fetuses for external, visceral, and skeletal malformations. A significant decrease in food consumption and body weight was observed in mothers, without any other manifestation of toxicity. In fetuses, no external malformations, visceral, or skeletal abnormalities, were observed under the dose of 100 mg/kg, while the dose of 200 mg/kg caused malformations in low frequency in brain and kidneys. In view of the results obtained, DL-HEPB could be a good starting point for the design of new highly effective anticonvulsant agents, with much lower developmental toxicity than that shown by commercial anticonvulsants.

GluN2B subunit selective N-methyl-D-aspartate receptor ligands: Democratizing recent progress to assist the development of novel neurotherapeutics

N-methyl-D-aspartate receptors (NMDARs) play essential roles in vital aspects of brain functions. NMDARs mediate clinical features of neurological diseases and thus, represent a potential therapeutic target for their treatments. Many findings implicated the GluN2B subunit of NMDARs in various neurological disorders including epilepsy, ischemic brain damage, and neurodegenerative disorders such as Parkinson's disease, Alzheimer's disease, Huntington's chorea, and amyotrophic lateral sclerosis. Although a large amount of information is growing consistently on the importance of GluN2B subunit, however, limited recent data is available on how subunit-selective ligands impact NMDAR functions, which blunts the ability to render the diagnosis or craft novel treatments tailored to patients. To bridge this gap, we have focused on and summarized recently reported GluN2B selective ligands as emerging subunit-selective antagonists and modulators of NMDAR. Herein, we have also presented an overview of the structure-function relationship for potential GluN2B/NMDAR ligands with their binding sites and connection to CNS functionalities. Understanding of design rules and roles of GluN2B selective compounds will provide the link to medicinal chemists and neuroscientists to explore novel neurotherapeutic strategies against dysfunctions of glutamatergic neurotransmission.

Multi-Mechanistic Approaches to the Treatment of Traumatic Brain Injury: A Review

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. Despite extensive research efforts, the majority of trialed monotherapies to date have failed to demonstrate significant benefit. It has been suggested that this is due to the complex pathophysiology of TBI, which may possibly be addressed by a combination of therapeutic interventions. In this article, we have reviewed combinations of different pharmacologic treatments, combinations of non-pharmacologic interventions, and combined pharmacologic and non-pharmacologic interventions for TBI. Both preclinical and clinical studies have been included. While promising results have been found in animal models, clinical trials of combination therapies have not yet shown clear benefit. This may possibly be due to their application without consideration of the evolving pathophysiology of TBI. Improvements of this paradigm may come from novel interventions guided by multimodal neuromonitoring and multimodal imaging techniques, as well as the application of multi-targeted non-pharmacologic and endogenous therapies. There also needs to be a greater representation of female subjects in preclinical and clinical studies.

Possible Interaction of Opioidergic and Nitrergic Pathways in the Anticonvulsant Effect of Ivermectin on Pentylenetetrazole-Induced Clonic Seizures in Mice

Ivermectin (IVM) is an antiparasitic drug that primarily works by the activation of GABA_A receptors. The potential pharmacological pathways behind the anti-convulsant effect of IVM haven't yet been identified. In this study, intravenous injection of pentylenetetrazole (PTZ)-induced clonic seizure in mice was investigated in order to assess the possible influence of IVM on clonic seizure threshold (CST). We also look at the function of the Opioidergic and nitrergic pathways in IVM anticonvulsant action on clonic seizure threshold. IVM (0.5, 1, 5, and 10 mg/kg, i.p.) raised the PTZ-induced CST, according to our findings. Furthermore, the ineffective dose of nitric oxide synthase inhibitors (L-NAME 10 mg/kg, i.p.), and (7-NI 30 mg/kg, i.p.) or opioidergic system agonist (morphine 0.25 mg/kg, i.p.) were able to amplify the anticonvulsive action of IVM (0.2 mg/kg, i.p.). Moreover, the anticonvulsant effect of IVM was reversed by an opioid receptor antagonist (naltrexone 1 mg/kg, i.p.). Furthermore, the combination of the ineffective dose of morphine as an opioid receptor agonist with either L-NAME (2 mg/kg, i.p.) or 7-NI (10 mg/kg, i.p.) and with an ineffective dose of IVM (0.2 mg/kg, i.p.) had a significant anticonvulsant effect. Taken together, IVM has anticonvulsant activity against PTZ-induced clonic seizures in mice, which may be mediated at least in part through the interaction of the opioidergic system and the nitric oxide pathway.

A simple and easy non-derivatization gas chromatography-mass spectrometry method for simultaneous quantification of valproic acid, gabapentin, pregabalin, and vigabatrin in human plasma

Immunoassays are currently not available in commercial kits for the quantification of valproic acid, vigabatrin, pregabalin, and gabapentin, which also cannot suffer the limitations of interferences of substances with similar structures. Chromatography is a good alternative to immunoassay. In this study, a simple and robust non-derivatization gas chromatography-mass spectrometry method for simultaneous determination of the above four drugs in human plasma was developed and validated for therapeutic drug monitoring purposes. This method employed benzoic acid as the internal standard with hydrochloric acid for plasma acidification and ACN for precipitate protein. The supernatant was directly injected into gas chromatography-mass spectrometry for analysis. Good linearity was obtained with linear correlation coefficients of the four analytes of 0.9988-0.9996. Extraction recoveries of valproic acid, vigabatrin, pregabalin, and gabapentin were respectively in the ranges of 91.3%-94.5%, 90.0%-90.9%, 90.0%-92.1%, and 88.0%-92.2% with the relative standard deviation values less than 12.6%. Intra- and inter-batch precision and accuracy, and stability assays were all acceptable. Taken together, the novel method developed in this study provided easy plasma pretreatment, good extraction yield, and high chromatographic resolution, which has been successfully validated through the quantification of valproic acid in the plasma of 46 patients with epilepsy.

Carbamazepine-induced renal toxicity may be associated with oxidative stress and apoptosis in male rat

Carbamazepine (CBZ) is the antiepileptic drug used in epilepsy and some psychiatric disorders. Besides its widely used, many adverse effects have been reported including hematotoxicity, hepatotoxicity, endocrine disorders, and testicular damages due to oxidative stress. However, the role of CBZ on renal toxicity is not fully known. In this study, we attempted to explain the connected mechanisms by focusing on the metabolism of CBZ-induced renal toxicity in rats. Twenty male Wistar-Albino rats were randomized into 2 groups (n = 10); control (1 mL/day distilled water, orally) and CBZ (25 mg/kg/day CBZ, orally) groups. After 60 days, TAS (total oxidant status) and TOS (total oxidant status) levels, histopathological features, some genes involved in apoptosis, 8-hydroxy-2-deoxyguanosine (8-OHdG) activity, and apoptotic cells were assessed of kidney tissue. The oxidative stress index (OSI) was measured from TAS and TOS levels. TOS levels and OSI significantly increased, while TAS levels decreased in the CBZ group relative to the control group. Histopathological observations, Caspase-3 (Casp3), Poly [ADP-ribose] polymerase-1 (PARP-1), 8-OHdG immunoreactivities, and apoptotic cells markedly raised in the CBZ group compared with the control group. Also, mRNA expression of Cytochrome c (Cytc) and CASP3 significantly increased in the CBZ group compared to the control group. In conclusion, long-term use of CBZ may promote renal damage in rats by inducing oxidative stress and apoptosis.

Eslicarbazepine acetate is porphyrogenic and should be used with caution in patients with the acute hepatic porphyrias

Eslicarbazepine acetate, a third-generation antiepileptic drug (AED), has shown improved clinical response and safety in comparison to older generation AEDs for patients with partial-onset seizures. It is currently not known whether eslicarbazepine acetate is safe to use in patients with the acute hepatic porphyrias (AHPs) since a few first-generation AEDs, such as phenobarbital and carbamazepine, are known porphyrogenic agents. In this study, we used a recently published in vitro fluorescence-based screening assay to screen for porphyrogenicity in various agents. The assay confirmed that among the tested compounds used, allyl isopropyl acetamide, carbamazepine, eslicarbazepine acetate, and phenobarbital were porphyrogenic. Thus, eslicarbazepine acetate should be avoided if possible in patients with the AHPs, but if initiated, patients should be closely monitored and the drug should be discontinued if a porphyric exacerbation occurs.

Prescription trends in anti-seizure medications for adult patients with epilepsy in Japan: A retrospective cohort study using the database of health insurance claims between 2015 and 2019

OBJECTIVE

To investigate whether newer anti-seizure medications (ASMs) are widely prescribed for a range of adult patients in Japan, including patients with previously and newly diagnosed epilepsy, or with focal and generalized epilepsies.

METHODS

A retrospective cohort study was conducted using the Japanese insurance claims database including 8.4 million people to identify adults (≥16 years of age) with epilepsy diagnosis code identified between January 2015 and December 2018. Patients were included in the prevalent population if epilepsy was already diagnosed at baseline, and in the incident population if prior baseline data for at least 12 months included no epilepsy diagnosis code or ASM prescription. Patients were followed up from the month when the initial oral ASM was prescribed for up to 4 years until the end of 2019 as long as at least one ASM was prescribed. Proportions of prescribed oral ASMs were analyzed by population with epilepsy (prevalent vs. incident) and classification (focal vs. generalized). Anti-seizure medications were classified into older vs. newer ASMs according to the date of approval before and after 1990, respectively.

RESULTS

A total of 24,691 patients fulfilled the eligibility criteria for the analysis. Of these, 21,046 and 3,645 were included in the prevalent and incident populations, respectively. The proportion of older ASMs significantly decreased, whereas the proportion of newer ASMs significantly increased (p < 0.0001) during the study period. This trend was more apparent in the population with incident epilepsy than in that with prevalent epilepsy, and was also apparent in the subgroup of focal epilepsy, but not in that of generalized epilepsy. Levetiracetam was the most frequently prescribed of the newer ASMs.

CONCLUSION

Newer ASMs became more widely prescribed throughout the study period in populations with both prevalent and incident epilepsies, as well as the subpopulation with focal epilepsy. The advantages of newer ASMs such as better safety profiles may have led to the increasing proportions of prescriptions and newer ASMs may increase the treatment options for patients.

The real-world effectiveness and safety of perampanel in Europe: A scoping review

In order to characterize the real-world effectiveness and safety of perampanel during clinical use in Europe, we conducted a structured literature search and scoping review of real-world studies conducted in Europe in adolescents (aged ≥ 12 years) or adults who were prescribed perampanel for focal epilepsy or primary generalized tonic-clonic seizures in the context of idiopathic generalized epilepsy, published between January 2016 and July 2021. We identified 29 relevant studies (20 retrospective and 9 prospective) in 3608 patients; median study duration was 12 months. Most patients (76.1%) were receiving two or more antiseizure drugs (ASDs) when perampanel was initiated. The maintenance perampanel dose ranged from 2 to 16 mg/day (most commonly 6 mg/day). Retention rate at 12 months ranged from 46% to 90.5% (median 71.1%). The proportion of patients who were free of seizures during perampanel ranged from 1.8% to 84.6%, but were consistently below 20% in studies where patients had received an average of ≥5 prior ASDs and above 20% where patients had received an average of <5 prior ASDs. The proportion of patients who achieved ≥50% reduction in seizures during perampanel ranged from 20.0% to 85.7%. Across all studies, the incidence of adverse events (AEs) ranged from 18.2% to 67.4% (median 37.1%) and discontinuation due to AEs from 6.2% to 56% (median 12.5%). Discontinuation rates tended to be higher in UK studies than in studies from Italy or Spain. The most commonly reported individual AEs were dizziness/vertigo (median incidence 13.7%), somnolence (median 11.9%), aggression (median 9.8%), irritability (median 9.1%), and cognitive deficits (median 7.0%). There was no relationship between the overall rate of AEs and perampanel dose, perampanel plasma levels, or number of concomitant medications. Our global overview of European observational studies with perampanel provides evidence that this agent is effective and safe in clinical practice in a range of countries, patients, and settings.

Fruits for Seizures? A Systematic Review on the Potential Anti-Convulsant Effects of Fruits and their Phytochemicals

Epilepsy is a devastating neurological disorder. Current anti-convulsant drugs are only effective in about 70% of patients, while the rest remain drug-resistant. Thus, alternative methods have been explored to control seizures in these drug-resistant patients. One such method may be through the utilization of fruit phytochemicals. These phytochemicals have been reported to have beneficial properties such as anti-convulsant, anti-oxidant, and anti-inflammatory activities. However, some fruits may also elicit harmful effects. This review aims to summarize and elucidate the anti- or pro-convulsant effects of fruits used in relation to seizures in hopes of providing a good therapeutic reference to epileptic patients and their carers. Three databases, SCOPUS, ScienceDirect, and PubMed, were utilized for the literature search. Based on the PRISMA guidelines, a total of 40 articles were selected for critical appraisal in this review. Overall, the extracts and phytochemicals of fruits managed to effectively reduce seizure activities in various preclinical seizure models, acting mainly through the activation of the inhibitory neurotransmission and blocking the excitatory neurotransmission. Only star fruit has been identified as a pro-convulsant fruit due to its caramboxin and oxalate compounds. Future studies should focus more on utilizing these fruits as possible treatment strategies for epilepsy.

Acute symptomatic seizures and status epilepticus in older adults: A narrative review focusing on management and outcomes

A clear narrative of acute symptomatic seizures (ASyS) in older adults is lacking. Older adults (≥60 years) have the highest incidence of seizures of all age groups and necessitate a tailored approach. ASyS has a bimodal peak in infancy and old age (82.3–123.2/100,000/year after 65 years of age). ASyS can represent half of the new-onset seizures in older adults and can progress to acute symptomatic status epilepticus (ASySE) in 52–72% of the patients. Common etiologies for ASyS in older adults include acute stroke and metabolic disturbances. For ASySE, common etiologies are acute stroke and anoxic brain injury (ABI). Initial testing for ASyS should be consistent with the most common and urgent etiologies. A 20-min electroencephalogram (EEG) is less sensitive in older adults than in younger adults and might not help predict chronic epilepsy. The prolonged postictal phase is an additional challenge for acute management. Studies note that 30% of older adults with ASyS subsequently develop epilepsy. The risk of wrongly equating ASyS as the first seizure of epilepsy is higher in older adults due to the increased long-term challenges with chronic anti-seizure medication (ASM) treatment. Specific challenges to managing ASyS in older adults are related to their chronic comorbidities and polypharmacy. It is unclear if the prognosis of ASyS is dependent on the underlying etiology. Short-term mortality is 1.6 to 3.6 times higher than younger adults. ASySE has high short-term mortality, especially when it is secondary to acute stroke. An acute symptomatic etiology of ASySE had five times increased risk of short-term mortality compared to other types of etiology.

Analysis of signal components < 500 Hz in brain organoids coupled to microelectrode arrays: A reliable test-bed for preclinical seizure liability assessment of drugs and screening of antiepileptic drugs

Brain organoids with three-dimensional structure and tissue-like function are highly demanded for brain disease research and drug evaluation. However, to our knowledge, methods for measuring and analyzing brain organoid function have not been developed yet. This study focused on the frequency components of an obtained waveform below 500 Hz using planner microelectrode array (MEA) and evaluated the response to the convulsants pentylenetetrazol (PTZ) and strychnine as well as the antiepileptic drugs (AEDs) perampanel and phenytoin. Sudden and persistent seizure-like firing was observed with PTZ administration, displaying a concentration-dependent periodic activity with the frequency component enhanced even in one oscillation characteristic. On the other hand, in the administration of AEDs, the frequency of oscillation decreased in a concentration-dependent manner and the intensity of the frequency component in one oscillation also decreased. Interestingly, at low doses of phenytoin, a group of synchronized bursts was formed, which was different from the response to the perampanel. Frequency components contained information on cerebral organoid function, and MEA was proven useful in predicting the seizure liability of drugs and evaluating the effect of AEDs with a different mechanism of action. In addition, frequency component analysis of brain organoids using MEA is an important analysis method to perform in vitro to in vivo extrapolation in the future, which will help explore the function of the organoid itself, study human brain developments, and treat various brain diseases.

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Frequency analysis <500 Hz was performed in brain organoids coupled to planner microelectrode arrays (MEA).

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Concentration-dependent changes in frequency components were detected in responses to convulsants and antiepileptic drugs (AEDs).

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Analysis of signal components <500 Hz in brain organoids is a useful method for preclinical seizure liability assessment of drugs and screening of antiepileptic drugs.

Acute liver failure with thrombotic microangiopathy due to sodium valproate toxicity: A case report

BACKGROUND

Sodium valproate is widely used in the treatment of epilepsy in clinical practice. Most adverse reactions to sodium valproate are mild and reversible, while serious idiosyncratic side effects are becoming apparent, particularly hepatotoxicity. Herein, we report a case of fatal acute liver failure (ALF) with thrombotic microangiopathy (TMA) caused by treatment with sodium valproate in a patient following surgery for meningioma.

CASE SUMMARY

A 42-year-old man who received antiepileptic treatment with sodium valproate after surgery for meningioma exhibited extreme fatigue, severe jaundice accompanied by oliguria, soy sauce-colored urine, and ecchymosis. His postoperative laboratory values indicated a rapid decreased platelet count and hemoglobin level, severe liver and kidney dysfunction, and disturbance of the coagulation system. He was diagnosed with drug-induced liver failure combined with TMA. After plasma exchange combined with hemoperfusion, pulse therapy with high-dose methylprednisolone, and blood transfusion, his liver function deteriorated, and finally, he died.

CONCLUSION

ALF with TMA is a rare and fatal adverse reaction of sodium valproate which needs to be highly valued.

Risk of ischaemic stroke associated with antiepileptic drugs: a population-based case-control study in Catalonia

BACKGROUND

Cerebrovascular disorders have occurred more frequently in some Central Nervous System (CNS) disorders, such as epilepsy. Some CNS drugs have been associated with increased stroke risk. Our aim was to estimate the risk of ischaemic stroke in patients exposed to antiepileptic drugs (AED).

METHODS

Population-based matched case-control study using SIDIAP database, based in electronic health records from primary healthcare from Catalonia, Spain. Cases were those patients with a registered diagnosis of first stroke during 2009-2014. Up to 10 controls were selected for each case and matched by sex, age, and geographic area and without a prior diagnosis of stroke. We considered global drug exposure to AED, past and current exposure and exposure in monotherapy to each AED.

RESULTS

2,865 cases and 19,406 controls were exposed to AED during the study period. Global exposure to levetiracetam [(OR_adj3.3, CI95 % 2.8-4.0)], phenytoin [OR_adj1.5, CI95 % 1.2-41.9)], and valproic acid [(OR_adj 1.3, CI95 % 1.1-1.6)], showed significantly association to ischaemic stroke that was also maintained with current exposure of levetiracetam [OR_adj4.1, CI95 % 3.3-5.2)] and valproic acid [OR_adj1.4, CI95 % 1.1-1.9)]. Current levetiracetam monotherapy showed a very high risk of ischaemic stroke [(OR_adj 5.1, CI95 % 3.7-6.9)].

CONCLUSIONS

Drugs used for other conditions than epilepsy (pregabalin, gabapentin) were the most used AED and both did not show a risk. Levetiracetam shows a risk for stroke even when assessed in current monotherapy. The lack of data regarding the link with diagnosis and severity in our study makes it necessary to conduct further studies to confirm or dismiss our results, focussing on levetiracetam.

Conifers Phytochemicals: A Valuable Forest with Therapeutic Potential

Conifers have long been recognized for their therapeutic potential in different disorders. Alkaloids, terpenes and polyphenols are the most abundant naturally occurring phytochemicals in these plants. Here, we provide an overview of the phytochemistry and related commercial products obtained from conifers. The pharmacological actions of different phytochemicals present in conifers against bacterial and fungal infections, cancer, diabetes and cardiovascular diseases are also reviewed. Data obtained from experimental and clinical studies performed to date clearly underline that such compounds exert promising antioxidant effects, being able to inhibit cell damage, cancer growth, inflammation and the onset of neurodegenerative diseases. Therefore, an attempt has been made with the intent to highlight the importance of conifer-derived extracts for pharmacological purposes, with the support of relevant in vitro and in vivo experimental data. In short, this review comprehends the information published to date related to conifers' phytochemicals and illustrates their potential role as drugs.

Seizures in systemic lupus erythematosus: A scoping review

Systemic lupus erythematosus is a systemic autoimmune disease that affects the central nervous system, either by direct neuronal damage, injury to brain vessels, or by pathogenic mechanisms indirectly induced by immune mechanisms related to the production and deposition of immune complexes. The prevalence of explicit episodes of seizures among SLE patients, varies from 2 to 8%. In some cases, patients with positivity for antiphospholipid or anti-β2 glycoprotein antibodies are found to be more prone to exhibit seizures compared to seronegative patients, other subjects at risk are carries of gene abnormalities codifying for ion channels. The exclusion of vasculitis or thrombosis is required for accurate treatment, imaging studies and alternative sequences are mandatory in patients with known SLE who present with a seizure. Several statements regarding SLE-related seizure remain to be decoded. In this scoping review we analyzed published information about prevalence, pathogenesis, clinical characteristics, diagnostic and therapeutic SLE patients that manifest a seizure, our objective is to provide with useful information for prompt diagnosis and individualized treatment.

Association between antiseizure medication use and risk of urinary tract infection: A case-control study

AIM

The aim of this study was to analyze the association between antiseizure medication (ASM) and the risk of urinary tract infections (UTI) in patients with epilepsy treated in general practices in Germany.

METHODS

This study includes a total of 2201 patients (mean age: 61.4) whose first documented UTI diagnosis occurred between January 2015 and December 2019 (index date) and who were prescribed at least one ASM in 1198 general practices in Germany within one year prior to the index date. Based on a case-control design, the association between predefined criteria and UTI was investigated by matching (1:1) controls without UTI to cases with UTI by sex, age, and codiagnoses. Logistic regression models were used to analyze the association between ASM use and UTI risk.

RESULTS

In the first regression model, phenytoin (PHT), primidone, carbamazepine (CBZ), and valproate (VPA) were associated with an increased risk of UTI. In the second model, these associations were confirmed with effects per prescription for PHT, primidone, CBZ, and VPA use. Additionally, the effect per prescription was significant for oxcarbazepine (OXC), topiramate, and gabapentin.

CONCLUSION

The study found that PHT, primidone, CBZ, and VPA in particular are associated with an increased risk of infections of the urinary tract. Oxcarbazepine, topiramate, and gabapentin are also associated with increased risk of UTI, albeit to a less significant extent. In general, the immunological and hematological side effects of these molecules may play an important role in the development of UTI under anticonvulsant therapy.

Computer-aided identification of human carbonic anhydrase isoenzyme VII inhibitors as potential antiepileptic agents

Human carbonic anhydrase (hCA) belongs to a superfamily of metalloenzymes that reversibly catalyse the hydration of carbon dioxide to give bicarbonate (HCO₃^-) and proton (H⁺). As HCO₃^- ions play an important role in neuronal signalling hence, hCA enzymes are an attractive target for antiepileptic drugs. Out of all the isoforms, hCA VII is predominantly expressed in the brain cortex and hippocampus region, which are the most affected area during seizure activity. Hence, we have identified some hCA VII inhibitors employing computational tools like atom-based 3D quantitative structure-activity relationship (QSAR), auto-QSAR, pharmacophore-based virtual screening, molecular docking, and molecular dynamics (MD) simulations. Atom-based 3D QSAR modelling outperformed auto-QSAR with an R² and Q² value of 0.9634 and 0.9646, respectively. A four-feature pharmacophore model (AADR_1) was developed and a focussed library of around 3,00,000 compounds was screened. Compounds with a phase screen score >2.40 were selected for docking studies. The activity of the selected hits was predicted employing the developed 3D QSAR model. Finally, three compounds were taken up for the MD simulation studies which also suggest that the identified hits might form a stable complex with hCA VII enzyme. A comparative docking study was also done with other hCA isoforms like I, II, IV, IX, and XII to examine the selectivity of the identified hits towards hCA VII. Based on these studies, three hits have been identified as potential hCA VII inhibitor which is drug-like molecules. Further, in vitro studies are required to develop leads from these identified hits.Communicated by Ramaswamy H. Sarma.

Epilepsy management in pregnant HIV+ women in sub-Saharan Africa, clinical aspects to consider: a scoping review

BACKGROUND

Since the introduction of highly active antiretroviral therapy (HAART), acquired immune deficiency syndrome (AIDS) related mortality has markedly declined. As HAART is becoming increasingly available, the infection with human immunodeficiency virus (HIV+) in sub-Saharan Africa (SSA) is becoming a chronic condition. While pregnancy in HIV+ women in SSA has always been considered a challenging event for the mother and the fetus, for pregnant HIV+ women also diagnosed with epilepsy (WWE), there are additional risks as HIV increases the odds of developing seizures due to the vulnerability of the central nervous system to other infections, immune dysfunction, and overall metabolic disturbances. In light of a growing proportion of HIV+ WWE on HAART and an increasing number of pregnant women accessing mother-to-child transmission of HIV programs through provision of HAART in SSA, there is a need to develop contextualized and evidenced-based clinical strategies for the management of epilepsy in this population. In this study, we conduct a literature scoping review to identify issues that warrant consideration for clinical management.

RESULT

Twenty-three articles were retained after screening, which covered six overarching clinical aspects: status epilepticus (SE), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), dyslipidemia, congenital malformation (CM), chronic kidney disease (CKD), and neurological development. No studies for our population of interest were identified, highlighting the need for a cautionary approach to be employed when extrapolating findings.

CONCLUSION

High risks of CM and drug interactions with first-line antiepileptic drugs (AEDs) warrant measures to increase the accessibility and choices of safer second-line AEDs. To ensure evidence-based management of epilepsy within this population, the potential high prevalence of SE, CKD, dyslipidemia, and SJS/TEN and the cumulative effect of drug-drug interactions should be considered. Further understanding of the intersections between pregnancy and drug-drug interactions in SSA is needed to ensure evidenced-based management of epilepsy in pregnant HIV+ WWE. To prevent SE, the barriers for AED treatment adherence in pregnant HIV+ women should be explored. Our review underscores the need to conduct cohort studies of HIV+ WWE in reproductive age over time and across pregnancies to capture the cumulative effect of HAART and AED to inform clinical management.

Incidence rates of severe cutaneous adverse reactions due to antiseizure medication: A nationwide study using health claims data in Korea

OBJECTIVE

Antiseizure medications (ASMs) can rarely result in severe, sometimes fatal, cutaneous adverse reactions. To date, few studies have reported on the incidence rates (IRs) of severe cutaneous adverse reactions (SCARs) due to ASM use. This study aimed to determine the IRs of SCAR resulting from the use of seven commonly prescribed ASMs, carbamazepine (CBZ), phenytoin (PHT), oxcarbazepine (OXC), lamotrigine (LMT), zonisamide (ZNS), levetiracetam (LVT), and topiramate (TPM), and to compare the associated risks among the drugs.

METHODS

Using a nationwide health claims database, we selected all the patients prescribed with one of the target ASMs. We defined a SCAR case as the first hospitalization with one of three specific codes provided by the International Classification of Diseases, 10th revision (L511, L512, and L27). We then calculated the IR of SCARs according to each target ASM.

RESULTS

The IR of SCARs for each ASM was as follows: 870/1 000 000 person-years (PYs) for CBZ, 5750/1 000 000 PYs for PHT, 1490/1 000 000 PYs for OXC, 3860/1 000 000 PYs for LMT, 1540/1 000 000 PYs for ZNS, 830/1 000 000 PYs for LVT, and 400/1 000 000 PYs for TPM. Concomitant use of antibiotics and nonsteroidal anti-inflammatory drugs significantly increased the risk of SCARs with OXC, LVT, or TPM use. Comorbid skin disease was associated with a significantly higher IR of SCARs from CBZ, PHT, OXC, LMT, or LVT use.

SIGNIFICANCE

This is the first study in Asia to determine the IRs of SCARs for various ASMs and compare the rates across drugs using a large dataset. The results from this study should help clinicians select safer ASMs in practice.

Carbamazepine adversely altered the pituitary-testicular axis with resultant reproductive dysfunctions than levetiracetam or carbamazepine-levetiracetam adjuvant treatment in male Wistar rat

This study investigated the on-toward reactions of individual or adjunctive treatment with carbamazepine (CBZ) and levetiracetam (LEV) on the pituitary-testicular axis in male rats. Twenty-four male Wistar rats were randomised into 4 groups (n = 6) and received daily intraperitoneal (i.p) treatment of normal saline (0.1 ml/day); CBZ (25 mg/kg i.p); LEV (50 mg/kg i.p); or combination of CBZ (12.5 mg/kg) and LEV (25 mg/kg) for 4 weeks. The serum concentration of luteinising hormone (LH), follicle-stimulating hormone (FSH), and testosterone was determined. Also, the seminal profile and histomorphological status of the testis were determined. Data were analysed using descriptive and inferential statistics. The control and test groups were compared using Student's t test, analysis of variance (ANOVA), and Student-Newman-Keuls post hoc analysis where appropriate, while the results presented as mean ± SEM in graphs or tables. The level of significance was taken at p < .05. The percentage motility, viability, and concentration of FSH decreased significantly in all the treatment groups, while the testis was presented with various forms of histomorphological aberrations. This study concludes that CBZ, and CBZ + LEV adjunctive treatments alter the pituitary-testicular axis with evidence of hormonal deregulation and alteration in the reproductive functions' indices, while LEV treatment remains the safest.

Transcranial direct current stimulation (tDCS) affects neuroinflammation parameters and behavioral seizure activity in pentylenetetrazole-induced kindling in rats

Despite the introduction of new antiepileptic drugs, about 30 % of patients with epilepsy are refractory to drug therapy. Thus, the search for non-pharmacological interventions such as transcranial direct current stimulation (tDCS) may be an alternative, either alone or in combination with low doses of anticonvulsants. This study evaluated the effect of anodal (a-tDCS) and cathodal tDCS (c-tDCS) on seizure behavior and neuroinflammation parameters. Rats were submitted to the kindling model induced by pentylenetetrazole (PTZ) using diazepam (DZP) as anticonvulsant standard. tDCS groups were submitted to 10 sessions of a-tDCS or c-tDCS or SHAM-tDCS. Every 3 days they received saline (SAL), low dose of DZP (alone or in combination with tDCS) or effective dose of DZP 30 min before administration of PTZ, totaling 16 days of protocol. Neither a-tDCS nor c-tDCS reduced the occurrence of clonic forelimb seizures (convulsive motor seizures - stage 3 by the adapted Racine scale we based on). Associated with DZP, c-tDCS (c-tDCS/DZP0.15) increased the latency to first clonic forelimb seizure on the 10th and 16th days. Hippocampal IL-1β levels were reduced by c-tDCS and c-tDCS/DZP0.15. In contrast, these treatments induced an increase in cortical IL-1β levels. Hippocampal TNF-α levels were not altered by c-tDCS or a-tDCS, but c-tDCS and c-tDCS/DZP0.15 increased those levels in cerebral cortex. Cortical NGF levels were increased by c-tDCS and c-tDCS/DZP0.15. a-tDCS/DZP0.15 reduced hippocampal BDNF levels and c-tDCS/DZP0.15 increased these levels in cerebral cortex. In conclusion, c-tDCS alone or in combination with a low dose of DZP showed to affect neuroinflammation, improving central neurotrophin levels and decreasing hippocampal IL-1β levels after PTZ-induced kindling without statistically significant effect on seizure behavior.

Management of antiepileptic drug-induced nutrition-related adverse effects

Although antiepileptic drugs (AEDs) are mainstay of the treatment of epilepsy, they are associated with significant adverse effects. The present study reviews the adverse effects of AEDs on some of the nutrition-related issues, including bone health, body weight, glucose and lipid metabolism, vitamin homeostasis, antioxidant defense system, and pregnancy. This paper also provides some nutritional recommendations for people with epilepsy. Patients with epilepsy should be regularly evaluated with regard to their nutrition status and any possible nutritional problems. Daily intake of adequate amounts of all nutrients from various sources should be encouraged, especially for vulnerable groups such as children, adolescents, elderly, and pregnant women. When necessary, preventative or therapeutic supplementation with appropriate micronutrients could be helpful. Graphical abstract.

Levetiracetam add-on for drug-resistant focal epilepsy

BACKGROUND

Drug resistance is common in focal epilepsy. In this update, we summarised the current evidence regarding add-on levetiracetam in treating drug-resistant focal epilepsy. The original review was published in 2001 and last updated in 2012.

OBJECTIVES

To evaluate the effectiveness of levetiracetam when used as an add-on treatment for people with drug-resistant focal epilepsy.

SEARCH METHODS

We searched the Cochrane Register of Studies (CRS Web, which includes the Cochrane Epilepsy Group Specialized Register and CENTRAL), MEDLINE Ovid, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform (ICTRP) to November 2018. We contacted the manufacturers of levetiracetam and researchers in the field to seek any ongoing or unpublished trials.

SELECTION CRITERIA

Randomised, placebo-controlled trials of add-on levetiracetam treatment in people with drug-resistant focal epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trials for bias, extracted data, and evaluated the overall certainty of the evidence. Outcomes investigated included 50% or greater reduction in focal seizure frequency (response), treatment withdrawal, adverse effects (including a specific analysis of changes in behaviour), cognitive effects, and quality of life (QoL). Primary analysis was intention-to-treat. We performed meta-analysis for all outcomes using a Mantel-Haenszel approach and calculated risk ratios (RR), with 95% confidence intervals (CI) for all estimates apart from adverse effects (99% CIs). We assessed heterogeneity using a Chi² test and the I² statistic.

MAIN RESULTS

This update included 14 trials (2455 participants), predominantly possessing low risks of bias. Participants were adults in 12 trials (2159 participants) and children in the remaining two (296 participants). The doses of levetiracetam tested were 500 mg/day to 4000 mg/day in adults, and 60 mg/kg/day in children. Treatment ranged from 12 to 24 weeks. When individual doses were examined, levetiracetam at either 500 mg/day or 4000 mg/day did not perform better than placebo for the 50% or greater reduction in seizure frequency outcome (500 mg: RR 1.60, 95% CI 0.71 to 3.62; P = 0.26; 4000 mg: RR 1.64, 95% CI 0.59 to 4.57; P = 0.34). Levetiracetam was significantly better than placebo at all other individual doses (1000 mg to 3000 mg). RR was significantly in favour of levetiracetam compared to placebo when results were pooled across all doses (RR 2.37, 95% CI 2.02 to 2.78; 14 studies, 2455 participants; moderate-certainty evidence). Dose-response analysis demonstrated that the odds of achieving response (50% or greater reduction in seizure frequency) were increased by nearly 40% (odds ratio (OR) 1.39, 95% CI 1.23 to 1.58) for each 1000 mg increase in dose of levetiracetam. There were important levels of heterogeneity across multiple comparisons. Participants were not significantly more likely to experience treatment withdrawal with levetiracetam than with placebo (pooled RR 1.11, 95% CI 0.89 to 1.40; 13 studies, 2428 participants; high-certainty evidence). Somnolence was the most common adverse effect, affecting 13% of participants, and it was significantly associated with levetiracetam compared to placebo (pooled RR 1.62, 99% CI 1.19 to 2.20; 13 studies, 2423 participants; moderate-certainty evidence). Changes in behaviour were negligible in adults (1% affected; RR 1.79, 99% CI 0.59 to 5.41), but significant in children (23% affected; RR 1.90, 99% CI 1.16 to 3.11). Levetiracetam had a positive effect on some aspects of cognition and QoL in adults and worsened certain aspects of child behaviour.

AUTHORS' CONCLUSIONS

Overall, this review update finds that in both adults and children with drug-resistant focal epilepsy, levetiracetam added on to usual care is more effective than placebo at reducing seizure frequency, it is unlikely to be stopped by patients, and it has minimal adverse effects outside of potential worsening behaviour in children. These findings are unchanged from the previous review update in 2012. This review update contributes two key additional findings: 1. a 500 mg daily dose of levetiracetam is no more effective than placebo at reducing seizures; and 2. the odds of response (50% reduction in seizure frequency) are increased by nearly 40% for each 1000 mg increase in dose of levetiracetam. It seems reasonable to continue the use of levetiracetam in both adults and children with drug-resistant focal epilepsy.

Infrequent Monitoring of the Effects of Valproate and Carbamazepine Therapy in Patients With Epilepsy in Nigeria

Background

Carbamazepine and valproate are widely used in the treatment of epileptic seizures. However, these agents exhibit certain adverse effects including hematopoietic disorders (carbamazepine) and severe hepatotoxicity (valproate).

Purpose

To determine the extent of monitoring of the hematologic effects of carbamazepine as well as the extent of monitoring of the hepatic effects of valproate in patients with epilepsy receiving treatment with these agents.

Method

A cross-sectional antiepileptic drug use study using case notes of patients with epilepsy managed at the neurologic clinics of 2 tertiary medical facilities in Nigeria between January and December 2017.

Results

Carbamazepine was the most frequently prescribed antiepileptic drug (48.24%), followed by valproate (29.34%) and levetiracetam (9.24%). Pretreatment monitoring of hematologic effect was carried out in only 61.11% of patients placed on carbamazepine therapy while follow-up monitoring was done in 3.7% of these patients. Also, in patients placed on valproate therapy, pretreatment and follow-up monitoring of the hepatic effect was done in only 33.71% and 19.0% of the patients, respectively.

Conclusions

The extent of monitoring of the hematologic effects of carbamazepine, as well as the hepatic effects of valproate in the cohort studied, is poor.

Should Off Label Antiepileptic Drugs Be Used for Treatment of Infancy and Childhood Epilepsy? Discussions Based on a Dravet Syndrome Case Report

Epilepsy represents a burdensome neurological disorder with higher incidence before the age of 18 years. The treatment is medical and involves long-term administration of antiepileptic drugs (AED). There are known high-resistant syndromes with onset in infancy and childhood, Dravet syndrome, being one of them. It is a well-known fact that early seizures treatment prevents associated comorbidities, cognitive and motor disabilities, and improve long-term prognosis. There are several AEDs available but not all of them are approved for use in infants. This is due to the need for additional toxicology studies at this age and for development of suitable formulations.

A 14-month-old girl with Dravet syndrome was presented here. Prompt diagnosis was made based on clinical features and confirmed by the genetic tests. She partially responded to valproate and clobazam but continued to have prolonged febrile seizures. We added stiripentol after consulting reports of studies in infants younger than 2 years and after obtaining family consent. She responded well with decrease in episodes of status epilepticus and improvement in psychomotor development and stiripentol was tolerated well. Off label use of certain AEDs can benefit infants when there are no major pharmacokinetic differences in comparison to older children.

Cenobamate (YKP3089) as adjunctive treatment for uncontrolled focal seizures in a large, phase 3, multicenter, open-label safety study

Objective

During the development of cenobamate, an antiseizure medication (ASM) for focal seizures, three cases of drug reaction with eosinophilia and systemic symptoms (DRESS) occurred. To mitigate the rate of DRESS, a start‐low, go‐slow approach was studied in an ongoing, open‐label, multicenter study. Also examined were long‐term safety of cenobamate and a method for managing the pharmacokinetic interaction between cenobamate, a 2C19 inhibitor, and concomitant phenytoin or phenobarbital.

Methods

Patients 18‐70 years old with uncontrolled focal seizures taking stable doses of one to three ASMs were enrolled. Cenobamate 12.5 mg/d was initiated and increased at 2‐week intervals to 25, 50, 100, 150, and 200 mg/d. Additional biweekly 50 mg/d increases to 400 mg/d were allowed. During titration, patients taking phenytoin or phenobarbital could not have their cenobamate titration rate or other concomitant ASMs adjusted; phenytoin/phenobarbital doses could be decreased by 25%‐33%.

Results

At data cutoff (median treatment duration = 9 months), 1347 patients were enrolled, of whom 269 (20.0%) discontinued, most commonly due to adverse events (n = 137) and consent withdrawn for reason other than adverse event (n = 74); 1339 patients received ≥1 treatment dose (median modal dose = 200 mg). The most common treatment‐emergent adverse events (TEAEs) were somnolence (28.1%), dizziness (23.6%), and fatigue (16.6%). Serious TEAEs occurred in 108 patients (8.1%), most commonly seizure (n = 14), epilepsy (n = 5), and pneumonia, fall, and dizziness (n = 4 each). No cases of DRESS were identified. In the phenytoin/phenobarbital groups, 43.4% (36/114) and 29.7% (11/51) of patients, respectively, had their doses decreased. At the end of titration, mean plasma phenytoin/phenobarbital levels were generally comparable to baseline.

Significance

No cases of DRESS were identified in 1339 patients exposed to cenobamate using a start‐low (12.5 mg/d), go‐slow titration approach. Cenobamate was generally well tolerated in the long term, with no new safety issues found. Phenytoin/phenobarbital dose reductions (25%‐33%), when needed during cenobamate titration, maintained stable plasma levels.

Evaluation of adverse drug reaction profile of antiepileptic drugs in persons with epilepsy: A cross-sectional study

INTRODUCTION

Newer antiepileptic drugs (AEDs) are preferred over conventional AEDs with the perception of better safety profile and efficacy though there is a lack of confirmatory evidence. The present study assessed the adverse drug reactions' (ADRs) profile of AEDs prescribed in persons with epilepsy (PWE) as per the System Organ Class (SOC) and compared them on the basis of demographics and treatment pattern.

MATERIAL AND METHODS

This prospective, cross-sectional, and observational study was conducted in PWE attending Neurology Outpatient-Department from February 2016 to April 2019 who were presented with any ADR. World Health Organization-Uppsala Monitoring Centre (WHO-UMC) scale was used for the causality assessment of suspected ADRs.

RESULTS

Among the 1011 PWE on AEDs, male:female ratio was 622:389, adult:pediatric ratio 736:275, and conventional:newer AEDs ratio 624:387. Among monotherapy PWE (47.1%), commonly used AEDs were levetiracetam (34.4%), valproic acid (22.9%), carbamazepine (18.3%), phenytoin (11.9%), and other AEDs (12.5%). A total of 1990 ADRs (1.96 ADRs per PWE) were reported as per SOC; among them, newer vs. conventional AEDs did not reveal any significant difference; however, monotherapy vs. polytherapy showed differences in nervous system disorders (p = 0.01) and skin and subcutaneous tissue disorders (p = 0.005). Causality assessment revealed 0.3% certain, 27.3% probable, 61.3% possible, and 11.1% unlikely association of ADRs with AEDs. Depending on the ADRs, there was either withdrawal of AED (0.9%), reduction in dose (48.4%), or continuation in the same dose as before (50.7%).

CONCLUSION

The ADR analysis showed that newer AEDs were associated with a similar trend of ADRs as that of conventional AEDs. Thus, the choice among newer and conventional AEDs should preferably focus on the experience of better efficacy in addition to safety data.

Cannabidiol (CBD) Inhibited Rhodamine-123 Efflux in Cultured Vascular Endothelial Cells and Astrocytes Under Hypoxic Conditions

Despite the constant development of new antiepileptic drugs (AEDs), more than 30% of patients develop refractory epilepsy (RE) characterized by a multidrug-resistant (MDR) phenotype. The “transporters hypothesis” indicates that the mechanism of this MDR phenotype is the overexpression of ABC transporters such as P-glycoprotein (P-gp) in the neurovascular unit cells, limiting access of the AEDs to the brain. Recent clinical trials and basic studies have shown encouraging results for the use of cannabinoids in RE, although its mechanisms of action are still not fully understood. Here, we have employed astrocytes and vascular endothelial cell cultures subjected to hypoxia, to test the effect of cannabidiol (CBD) on the P-gp-dependent Rhodamine-123 (Rho-123) efflux. Results show that during hypoxia, intracellular Rho-123 accumulation after CBD treatment is similar to that induced by the P-gp inhibitor Tariquidar (Tq). Noteworthy, this inhibition is like that registered in non-hypoxia conditions. Additionally, docking studies predicted that CBD could behave as a P-gp substrate by the interaction with several residues in the α-helix of the P-gp transmembrane domain. Overall, these findings suggest a direct effect of CBD on the Rho-123 P-gp-dependent efflux activity, which might explain why the CBD add-on treatment regimen in RE patients results in a significant reduction in seizure frequency.

Novel effect of Arthrocen (avocado/soy unsaponifiables) on pentylenetetrazole-induced seizure threshold in mice: Role of GABAergic pathway

Arthrocen, an avocado/soy unsaponifiable (ASU)-containing agent, is now used in the clinic and has potentially to decrease joint inflammation and pain associated with mild to severe osteoarthritis. Phytosterols are the major component of Arthrocen with documented anti-inflammatory properties, antioxidant, and analgesic effects. Here, we evaluated ASU anticonvulsant effect by its oral administration in pentylenetetrazole (PTZ)-induced seizure threshold and Maximal Electroshock Seizure (MES) Models. Also, the involvement of N-methyl-d-aspartate (NMDA) receptor, benzodiazepine receptor, and nitric oxide (NO) pathway were studied in anticonvulsant effect of ASU in male NMRI mice. Acute administration of Arthrocen (150, 75, 30, 10 mg/kg) by oral gavage significantly (p < 0.001) increased the clonic seizure threshold induced by intravenous administration of PTZ. Nonspecific inducible NO synthase (NOS) inhibitor L-NAME (10 mg/kg) and a specific NMDA receptor antagonist MK-801 (0.05 mg/kg) did not affect the anticonvulsant effect of Arthrocen, while pretreatment with flumazenil (0.25 mg/kg), a selective benzodiazepine receptor antagonist, reversed this effect (p < 0.01). Also, Arthrocen treated mice did not affect tonic hindlimb extension in the MES model. The data showed that Arthrocen might produce its anticonvulsant effect by enhancing GABAergic neurotransmission and/or action in the brain.

Simultaneous Determination of Drugs Affecting Central Nervous System (CNS) in Bulk and Pharmaceutical Formulations Using Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS)

The quality of medications is important to maintain the overall health care of patients. This study aims to develop and validate a spectrophotometric method using multivariate curve resolution-alternating least squares (MCR-ALS) with correlation constraint for simultaneous resolution and quantification of selected drugs affecting the central nervous system (imipramine, carbamazepine, chlorpromazine, haloperidol, and phenytoin) in different pharmaceutical dosage forms. Figures of merit such as root-mean-square error of prediction, bias, standard error of prediction, and relative error of prediction for the developed method were calculated. High values of correlation coefficients ranged between 0.9993 and 0.9998 reflected high predictive ability of the developed method. The results are linear in the concentration range of 0.3-5 μg/mL for carbamazepine, 0.3-15 μg/mL for chlorpromazine, 0.5-10 μg/mL for haloperidol, 0.5-10 μg/mL for imipramine, and 3-20 μg/mL for phenytoin. The optimized method was successfully applied for the analysis of the studied drugs in their pharmaceutical products without any separation step. The optimized method was also compared with a reported HPLC method using Student's t test and F ratio at 95% confidence level, and the results showed no significant difference regarding accuracy and precision. The proposed chemometric method is fast, reliable, and cost-effective and can be used as an eco-friendly alternative to chromatographic techniques for the analysis of the studied drugs in commercial pharmaceutical products.

Efficacy and serum concentrations of perampanel for treatment of drug-resistant epilepsy in children, adolescents, and young adults: comparison of patients younger and older than 12 years

PURPOSE

Perampanel (PER) is a selective, non-competitive antagonist of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor. In Japan, PER is approved for patients with epilepsy who are at least 12 years old for the adjunctive treatment of primary generalised tonic-clonic seizures and partial-onset seizures (with or without secondary generalization). We surveyed the efficacy, adverse effects, and serum concentrations of PER, focusing especially on patients younger than 12 years of age.

METHODS

We retrospectively surveyed the clinical information of patients treated with PER and assessed the efficacy at 6 months after treatment initiation. We compared efficacy, adverse effects, and serum concentration in patients younger or older than 12 years of age. Responders were defined as those who experienced a ≥50% seizure reduction.

RESULTS

Eighty-four patients were enrolled. The average age of the younger group was 7.1 ± 3.3 (standard deviation) years compared to 16.4 ± 3.7 years in the older group. The responder rate was 42.9% (36/84). The responder rate did not differ between the two age groups (<12 years, 20/44, 45.4%; >12 years, 16/40, 40.0%; p = 0.78). The younger age group had a significantly lower concentration-to-dose (CD) ratio than the older age group (<12 years, 1849.8 ± 2209.3; >12 years, 3076.3 ± 3352.2, p = 0.02). Treatment-emergent adverse events (TEAEs) were observed in 22.6% (19/84) of patients, with the most common being somnolence (8/84, 9.5%).

CONCLUSION

PER may be an alternative to treat seizures in paediatric drug-resistant epilepsy. Serum concentrations of PER might be lower in patients younger than 12 years than in older patients.

An overview of structurally diversified anticonvulsant agents

There are several limited approaches to treat epilepsy in hospitals, for example, using medicines, surgery, electrical stimulation and dietary interventions. Despite the availability of all these new and old approaches, seizure is particularly difficult to manage. The quest for new antiepileptic molecules with more specificity and less CNS toxicity continues for medicinal chemists until a new and ideal drug arrives. This review covers new antiseizure molecules of different chemical classes, the exact mode of action of which is still unidentified. Newer agents include sulfonamides, thiadiazoles, semi- and thiosemicarbazones, pyrrolidine-2,5-diones, imidazoles, benzothiazoles and amino acid deriva tives. These new chemical entities can be useful for the design and development of forthcoming antiseizure agents.

MiR-206 inhibits epilepsy and seizure-induced brain injury by targeting CCL2

To determine the function of miR-206 in epilepsy. Epileptic rat model was established by intra-amygdala injection of kainic acid (KA). Expression levels of miR-206, C-C Motif Chemokine Ligand 2 (CCL2) and interleukin-1β (Il-1β) in hippocampus tissues was measured by reverse transcription-quantitative PCR (RT-qPCR) and western blot. Dual luciferase reporter assay was performed to determine the binding of miR-206 to 3' untranslated region (UTR) of CCL2. Finally, brain waves were recorded and Hematoxylin and eosin (HE) staining and Nissl's staining were performed on the epileptic rat injected with LPS, miR-206 agomir, adeno-associated virus (AAV) expressed CCL2 alone or in combination. Expression of miR-206 was specially decreased in hippocampus tissues compared to cortex in response to KA induced pathologic brain activity. Enforced expression of miR-206 by injection miR-206 agomir not only decreased seizure activity, but also protected KA-induced neuronal loss. And enforced expression of miR-206 suppressed increase of C-C Motif Chemokine Ligand 2 (CCL2) and interleukin-1β (Il-1β) which were induced by injection of KA or KA combined with lipopolysaccharide (LPS). Further more, results of dual luciferase reporter assay confirmed CCL2 was a target of miR-206. Finally, co-injection adeno-associated virus (AAV) expressed CCL2 with miR-206 agomir abolished the function of miR-206 agomir. Taken together, our results showed that expression of miR-206 could inhibit seizure-induced brain injury by targeting CCL2. Our results showed that expression of miR-206 could inhibit seizure-induced brain injury by targeting CCL2.

Effect of probiotic supplementation on seizure activity and cognitive performance in PTZ-induced chemical kindling

Epilepsy is one of the most common neurological disorders that severely affect life quality of many people worldwide. Ion transport in the neuronal membrane, inhibitory-excitatory mechanisms, and regulatory modulator systems have been implicated in the pathogenesis of epilepsy. A bidirectional communication is proposed between brain and gut where the brain modulates the gastrointestinal tract, and the gut can affect brain function and behavior. The gut microbiome takes an important role in health and disease where dysbiosis is involved in several neurological disorders. Probiotics as living microorganisms are beneficial to humans and animals when adequately administered. In the present work, we evaluated the effect of a probiotic bacteria mixture on seizure activity, cognitive function, and gamma-aminobutyric acid (GABA), nitric oxide (NO), malondealdehyde (MDA), and total antioxidant capacity (TAC) level of the brain tissue in the pentylenetetrazole (PTZ)-induced kindled rats. The Racine score and performance in water maze were considered as indices of the epileptic severity and the spatial learning and memory, respectively. We found that the probiotic supplementation substantially reduces seizure severity so that almost no probiotic-treated animals showed full kindling. The oral bacteriotherapy partially improved the spatial learning and memory in the kindled rats. The intervention decreased NO and MDA and increased TAC concentration of the brain. The probiotic treatment also increased the inhibitory neurotransmitter GABA. Our findings are the first preclinical report to show positive effect of probiotic bacteria on seizure-induced neurological disorders. Further investigation is required to answer the questions raised about the probable mechanisms involved.

Clinical Use and Monitoring of Antiepileptic Drugs

Background

Antiepileptic drugs (AEDs) have been used for the treatment of epilepsy and other neurological disorders since the late 19th century. There are currently several classes of AEDs available for epilepsy management, many of which are also used to treat migraines, bipolar disorder, schizophrenia, depression, and neuropathic pain. Because of their molecular and mechanistic diversity, as well as the potential for drug–drug interactions, AEDs are prescribed and monitored in a highly personalized manner.

Content

This review provides a general overview of the use of AEDs with a focus on the role of therapeutic drug monitoring. Discussed topics include mechanisms of action, guidelines on the clinical applications of AEDs, clinical tests available for AED monitoring, and genetic factors known to affect AED efficacy.

Summary

Implementation of AED therapies is highly individualized, with many patient-specific factors considered for drug and dosage selection. Both therapeutic efficacy and target blood concentrations must be established for each patient to achieve seizure mitigation or cessation. The use of an AED with any additional drug, including other AEDs, requires an evaluation of potential drug–drug interactions. Furthermore, AEDs are commonly used for nonepilepsy indications, often in off-label administration to treat neurological or psychiatric disorders.

Anticonvulsant and Antioxidant Effects of Musa sapientum Stem Extract on Acute and Chronic Experimental Models of Epilepsy

Background:

Musa sapientum (banana) plant extract has been shown to possess antioxidant activity in previous studies. Neuronal injury resulting from oxidative stress is an important factor involved in pathogenesis of epilepsy.

Objective:

The present study aimed to evaluate the anticonvulsant activity of M. sapientum stem extract (MSSE) in acute and chronic experimental models in mice and its effects on various markers of oxidative stress in the brain of pentylenetetrazole (PTZ)-kindled animals.

Material and Methods:

Maximal electroshock seizures (MES) and PTZ-induced convulsion models were used for acute studies. For the chronic study, the effect of MSSE on the development of kindling was studied. For the evaluation of the effects of MSSE on oxidative stress in brain, malondialdehyde (MDA) and reduced glutathione (GSH) levels were estimated in the brains of the kindled animals.

Results:

MSSE significantly increased the latency to onset of myoclonic jerks and the duration of clonic convulsions following PTZ administration. The MSSE pretreated group showed significantly reduced mean seizure score on PTZ-induced kindling. There was a significant increase in the brain MDA levels and decrease in GSH levels in response to PTZ-induced kindling. On MSSE pretreatment, there was a significant decrease in the MDA levels in the brains, though the increase in the GSH levels was not significant.

Conclusion:

The results from this study suggest the presence of significant anticonvulsant activity in MSSE, in both acute and chronic PTZ-induced seizure models, which could be due to its antioxidant activity, as is reflected by the change in oxidative stress markers in brain.

SUMMARY

Evaluation of the anticonvulsant activity of Musa sapientum and its effects on various markers of oxidative stress in the brain has not been done previously to the best of our knowledge

M. sapientum stem extract (MSSE) significantly increased the latency to onset of myoclonic jerks and the duration of clonic convulsions in the experimental models

The MSSE pretreated group showed significantly reduced mean seizure score on pentylenetetrazole (PTZ)-induced kindling

There was significant increase in the brain malondialdehyde (MDA) levels and decrease in glutathione (GSH) levels in response to PTZ-induced kindling

On MSSE pretreatment, there was a significant decrease in the MDA levels in the brain, though the increase in the GSH levels was not significant.

Abbreviations Used: MSSE: Musa sapientum stem extract, PTZ: Pentylenetetrazole, MES: Maximal electroshock seizures, MDA: Malondialdehyde, GSH: Glutathione, SOD: Superoxide dismutase, THLE: Tonic hindlimb extension

Pharmacodynamics and common drug-drug interactions of the third-generation antiepileptic drugs

INTRODUCTION

Anticonvulsants that belong to the third generation are considered as 'newer' antiepileptic drugs, including: eslicarbazepine acetate, lacosamide, perampanel, brivaracetam, rufinamide and stiripentol. Areas covered: This article reviews pharmacodynamics (i.e. mechanisms of action) and clinically relevant drug-drug interactions of the third-generation antiepileptic drugs. Expert opinion: Newer antiepileptic drugs have mechanisms of action which are not shared with the first and the second generation anticonvulsants, like inhibition of neurotransmitters release, blocking receptors for excitatory amino acids and new ways of sodium channel inactivation. New mechanisms of action increase chances of controlling forms of epilepsy resistant to older anticonvulsants. Important advantage of the third-generation anticonvulsants could be their little propensity for interactions with both antiepileptic and other drugs observed until now, making prescribing much easier and safer. However, this may change with new studies specifically designed to discover drug-drug interactions. Although the third-generation antiepileptic drugs enlarged therapeutic palette against epilepsy, 20-30% of patients with epilepsy is still treatment-resistant and need new pharmacological approach. There is great need to explore all molecular targets that may directly or indirectly be involved in generation of seizures, so a number of candidate compounds for even newer anticonvulsants could be generated.

Epilepsy treatment in adults and adolescents: Expert opinion, 2016

INTRODUCTION

There are over twenty anti-seizure medications and anti-seizure devices available commercially in the United States. The multitude of treatment options for seizures can present a challenge to clinicians, especially those who are not subspecialists in the epilepsy field. Many clinical questions are not adequately answered in double-blind randomized controlled studies. In the presence of a knowledge gap, many clinicians consult a respected colleague with acknowledged expertise in the field. Our survey was designed to provide expert opinions on the treatment of epilepsy in adults and adolescents.

METHOD

We surveyed a group of 42 physicians across the United States who are considered experts based on publication record in the field of epilepsy, or a leadership role in a National Association of Epilepsy Centers comprehensive epilepsy program. The survey consisted of 43 multiple-part patient scenario questions and was administered online using Redcap software. The experts provided their opinion on 1126 treatment options based on a modified Rand 9-point scale. The patient scenarios focused on genetically-mediated generalized epilepsy and focal epilepsy. The scenarios first focused on overall treatment strategy and then on specific pharmacotherapies. Other questions focused on treatment of specific patient populations (pregnancy, the elderly, patients with brain tumors, and post organ transplant patients), epilepsy patients with comorbidities (renal and hepatic disease, depression), and how to combine medications after failure of monotherapy. Statistical analysis of data used the expert consensus method.

RESULTS

Valproate was considered a drug of choice in all genetically-mediated generalized epilepsies, except in the population of women of child-bearing age. Ethosuximide was a drug of choice in patient with absence seizures, and levetiracetam was a drug of choice in patients with genetic generalized tonic-clonic seizures and myoclonic seizures. Lamotrigine, levetiracetam and oxcarbazepine were considered drugs of choice for initial treatment of focal seizures. Lamotrigine and levetiracetam were the drugs of choice for women of child-bearing age with either genetic generalized epilepsy or focal epilepsy. Lamotrigine and levetiracetam were the drugs of choice in the elderly population. Lamotrigine was preferred in patients with co-morbid depression. Levetiracetam was the drug of choice in treating patients with hepatic failure, or who have undergone organ transplantation. Compared to the 2005 and 2001 surveys, there was increased preference for the use of levetiracetam and lamotrigine, and decreased preference for the use of phenytoin, gabapentin, phenobarbital and carbamazepine.

DISCUSSION

The study presented here provides a "snapshot" of the clinical practices of experts in the treatment of epilepsy. The experts were very often in agreement, and reached consensus in 81% of the possible responses. However, expert opinion does not replace the medical literature; instead, it acts to supplement existing information. Using the study results is similar to requesting an expert consultation. Our findings suggest options that the clinician should consider to achieve best practice.

Thirty Years of Orphan Drug Legislation and the Development of Drugs to Treat Rare Seizure Conditions: A Cross Sectional Analysis

BACKGROUND

Epilepsy is a serious chronic health condition with a high morbidity impairing the life of patients and afflicted families. Many epileptic conditions, especially those affecting children, are rare disorders generating an urgent medical need for more efficacious therapy options. Therefore, we assessed the output of the US and European orphan drug legislations.

METHODS

Quantitative analysis of the FDA and EMA databases for orphan drug designations according to STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) criteria.

RESULTS

Within the US Orphan Drug Act 40 designations were granted delivering nine approvals, i.e. clobazam, diazepam viscous solution for rectal administration, felbamate, fosphenytoin, lamotrigine, repository corticotropin, rufinamide, topiramate, and vigabatrin. Since 2000 the EMA granted six orphan drug designations whereof two compounds were approved, i.e. rufinamide and stiripentol. In the US, two orphan drug designations were withdrawn. Orphan drugs were approved for conditions including Lennox-Gastaut syndrome, infantile spasms, Dravet syndrome, and status epilepticus. Comparing time to approval for rufinamide, which was approved in the US and the EU to treat rare seizure conditions, the process seems faster in the EU (2.2 years) than in the US (4.3 years).

CONCLUSION

Orphan drug development in the US and in the EU delivered only few molecular entities to treat rare seizure disorders. The development programs focused on already approved antiepileptic drugs or alternative pharmaceutical formulations. Most orphan drugs approved in the US are not approved in the EU to treat rare seizures although some were introduced after 2000 when the EU adopted the Orphan Drug Regulation.