Therapy For Refractory Epilepsy Research Articles

The cenobamate KORK study-A prospective monocenter observational study investigating cenobamate as an adjunctive therapy in refractory epilepsy, with comparisons to historical cohorts treated with add-on lacosamide, perampanel, and brivaracetam.

In Europe, cenobamate has been approved for use as an adjunctive therapy in adult patients with epilepsy (PWE) with focal-onset seizures (FOS) who have not responded satisfactorily to treatment with at least two antiseizure medications (ASMs). Pivotal trials and real-world observational studies have demonstrated a high efficacy of cenobamate, even in very difficult-to-treat epilepsies. Our aim was to investigate the efficacy of add-on cenobamate in adult PWE who were prospectively monitored. We compared these results with those previously obtained for add-on lacosamide, perampanel, and brivaracetam therapy. Patients were enrolled from the CENKORK study, which is a prospective, non-interventional, open-label, monocenter cohort study of adult PWE experiencing FOS. The titration of cenobamate was performed according to the guidelines outlined in the summary of product characteristics. The primary outcome measure was the retention rate at 6 months and 1 year. In addition, we assessed seizure-free rates, the proportion of patients achieving at least a 50% seizure reduction, adverse events, and the reasons for treatment discontinuation. These outcome measures were compared with historical controls treated with adjunctive lacosamide, perampanel, or brivaracetam at our center. Between June 2021 and 2022, 172 PWE with ongoing FOS were included. 22 cases were lost to follow-up, leaving 150 cases for the 1-year assessment. The retention rates at 6 months and 1 year were 88.7% and 80%, respectively. Seizure freedom was achieved in 14% of patients at both the 6-month and 1-year marks, while the ≥50% responder rates were 50% and 61%, respectively. The 6-month retention rate was significantly higher in cenobamate than in other ASMs (p < 0.001 for each comparator). Adverse events were significantly more common with perampanel (p < 0.001). Add-on cenobamate proved to be particularly efficacious compared to our experience with other recently introduced ASMs. This observational study was carried out in 172 adult patients with difficult-to-treat epilepsy who were treated with adjunctive cenobamate. After 1 year, the data of 150 patients could be analyzed. Seizure freedom, in the preceding 3 months, was achieved in 14%. The rate of PWE continuing cenobamate was 80%. In our hands, cenobamate showed promising efficacy and tolerability even when compared to other recently introduced antiseizure medications.

Vagus nerve stimulation for conservative therapy-refractive epilepsy and depression.

Numerous studies confirm that the vagus nerve stimulation (VNS) is an efficient, indirect neuromodulatory therapy with electrically induced current for epilepsy that cannot be treated by epilepsy surgery and is therapy-refractory and for drug therapy-refractory depression. VNS is an established, evidence-based and in the long-term cost-effective therapy in an interdisciplinary overall concept.Long-term data on the safety and tolerance of the method are available despite the heterogeneity of the patient populations. Stimulation-related side effects like hoarseness, paresthesia, cough or dyspnea depend on the stimulation strength and often decrease with continuing therapy duration in the following years. Stimulation-related side effects of VNS can be well influenced by modifying the stimulation parameters. Overall, the invasive vagus nerve stimulation may be considered as a safe and well-tolerated therapy option.For invasive and transcutaneous vagus nerve stimulation, antiepileptic and antidepressant as well as positive cognitive effects could be proven. In contrast to drugs, VNS has no negative effect on cognition. In many cases, an improvement of the quality of life is possible.iVNS therapy has a low probability of complete seizure-freedom in cases of focal and genetically generalized epilepsy. It must be considered as palliative therapy, which means that it does not lead to healing and requires the continuation of specific medication. The functional principle is a general reduction of the neuronal excitability. This effect is achieved by a slow increase of the effectiveness sometimes over several years. Responders are those patients who experience a 50% reduction of the seizure incidence. Some studies even reveal seizure-freedom in 20% of the cases. Currently, it is not possible to differentiate between potential responders and non-responders before therapy/implantation.The current technical developments of the iVNS generators of the new generation like closed-loop system (cardiac-based seizure detection, CBSD) reduce also the risk for SUDEP (sudden unexpected death in epilepsy patients), a very rare, lethal complication of epilepsies, beside the seizure severity.iVNS may deteriorate an existing sleep apnea syndrome and therefore requires possible therapy interruption during nighttime (day-night programming or magnet use) beside the close cooperation with sleep physicians.The evaluation of the numerous iVNS trials of the past two decades showed multiple positive effects on other immunological, cardiological, and gastroenterological diseases so that additional therapy indications may be expected depending on future study results. Currently, the vagus nerve stimulation is in the focus of research in the disciplines of psychology, immunology, cardiology as well as pain and plasticity research with the desired potential of future medical application.Beside invasive vagus nerve stimulation with implantation of an IPG and an electrode, also devices for transdermal and thus non-invasive vagus nerve stimulation have been developed during the last years. According to the data that are currently available, they are less effective with regard to the reduction of the seizure severity and duration in cases of therapy-refractory epilepsy and slightly less effective regarding the improvement of depression symptoms. In this context, studies are missing that confirm high evidence of effectiveness. The same is true for the other indications that have been mentioned like tinnitus, cephalgia, gastrointestinal complaints etc. Another disadvantage of transcutaneous vagus nerve stimulation is that the stimulators have to be applied actively by the patients and are not permanently active, in contrast to implanted iVNS therapy systems. So they are only intermittently active; furthermore, the therapy adherence is uncertain.

Sodium Valproate Combined With Topiramate vs. Sodium Valproate Alone for Refractory Epilepsy: A Systematic Review and Meta-Analysis.

Background: Among antiepileptic drugs (AEDs), sodium valproate alone or in the combination of topiramate (TPM) for treating refractory epilepsy was controversial. This meta-analysis aimed to systematically evaluate the clinical effects of these two regimens in this population.Methods: Relevant studies up to August 2021 were identified through systematic searches of CNKI, Wanfang, PubMed, and Embase databases. We assessed the effectiveness and the frequency of absence seizures, atonic seizures, and tonic–clonic seizures. The included literature's risk of bias was evaluated using the Cochrane Collaboration's Risk of Bias tool. Sensitivity analysis was conducted to confirm the results' stability. STATA 15.0 was utilized for all pooled analyses in the included studies.Results: Totally 10 articles were determined for our meta-analysis, involving 976 patients with epilepsy in total (combined group, n = 488; monotherapy group, n = 488). The results of this meta-analysis indicated that the total effective rate of sodium valproate combined with TPM was higher than that of sodium valproate alone (random-effect model: OR = 3.52; 95% CI 1.47 to 8.47; p < 0.001; I2 = 73.8%). The frequency of absence seizures in the combined group was lower (fixed-effect model: WMD = −6.02; 95% CI −6.50 to −5.54; I2 = 0.0%) than that in the monotherapy group, with a statistical difference (p < 0.05). The combined group had lower frequency of atonic seizures (WMD = −4.56, 95% CI −6.02 to −3.10; I2 = 82.6%) and lower frequency of tonic–clonic seizures (WMD = −3.32; 95% CI −4.75 to −1.89; I2 = 96.4%). In addition, the distinct difference of adverse events was non-existent between two groups.Conclusions: Sodium valproate combined with TPM was more effective than sodium valproate alone for epilepsy therapy. This meta-analysis provides feasibility data for a larger-scale study on AED therapy of refractory epilepsy and may contribute to better therapy strategies for epilepsy clinically.

Fluoxetine as adjunctive therapy in pediatric patients with refractory epilepsy: A retrospective analysis

Approximately 30 % of children with epilepsy develop refractory epilepsy, which has a major impact on neurodevelopmental processes, cognitive functioning, and daily life. Furthermore, children with highly refractory epilepsy are at particular risk of sudden unexpected death. Fluoxetine, a selective serotonin reuptake inhibitor (SSRI), has shown antiseizure action and was associated with a decreased severity of peri-ictal hypoxemia in adult patients with focal epilepsy. However, therapeutic studies on SSRI use in children are scarce — particularly in epileptic patients.We retrospectively recruited 14 pediatric patients; inclusion criteria were i) refractory epilepsy ii) frequent generalized or focal seizures (more than 1/week) iii) treated with fluoxetine as adjunctive therapy for one month at least. We analyzed their clinical outcome (efficacy and tolerance). The median age at fluoxetine initiation was 9.5 years (2–19), and fluoxetine was combined with a median number of 4 (2–6) anti-seizure medications. The median dose of fluoxetine at the last follow-up was 0.4 mg/kg/day (0.2−0.8).Among the 14 patients, we observed 6 (43 %) good responders. Complete freedom from seizures with cyanosis was reached in 3 (21 %) patients, and only one patient with early-onset epilepsy related to an FHF1 mutation was completely seizure-free. None of the recruited patients experienced seizure worsening, and 8 patients showed no effect on seizure frequency.Fluoxetine as adjunctive therapy in refractory epilepsy could be a beneficial therapeutic option. Future prospective, randomized and controlled studies are needed to study the efficacy of fluoxetine better.

A Volumetric Absorptive Microsampling Technique to Monitor Cannabidiol Levels in Epilepsy Patients.

Purpose: Interest in cannabis-based therapies has recently increased, due to the availability of cannabidiol (CBD) for the treatment of epilepsy without psychoactive effects. Therapeutic drug monitoring can prevent drug interactions and minimize drug toxicity. We evaluated a volumetric absorptive microsampling (VAMS) method combined with LC-MS/MS (liquid chromatography coupled to tandem mass spectrometry) for the quantification of CBD blood levels in patients with refractory epilepsy. Methods: Prospective observation of patients with Dravet syndrome receiving open-label, add-on GW-purified CBD (Epidyolex®) at different doses. CBD plasma samples were obtained from venipuncture and LC-MS/MS was used to measure CBD in venous and capillary blood samples collected by VAMS. Results: We enrolled five patients with a mean age of 13 (range: 4–27) years. CBD levels measured by VAMS on capillary blood did not differ from CBD levels measured in plasma by venipuncture (R 2 > 0.93). Conclusion: This proof-of-concept study suggests that VAMS allows monitoring of CBD plasma levels and can offer valuable support for personalized therapy in refractory epilepsy.

Deep Brain Stimulation for Epilepsy: Biomarkers for Optimization.

Two large-scale controlled clinical trials have provided Class I evidence for the benefit of deep brain stimulation (DBS) as a therapy for refractory epilepsy. However, the efficacy has been variable, with some patients not achieving any improvement in their seizure control. This disparity could be the result of suboptimal stimulation parameters/electrodes or alternatively a difference in the type of seizures being treated. This review presents the most recent clinical results with a focus on two major targets for DBS, the anterior nucleus of the thalamus (ANT) and the hippocampus. We detail the etiologies where DBS might work best, and provide evidence for the use of recorded neural responses for the optimization of stimulation parameters and closed-loop control of devices. Stimulation of the hippocampus may work well for both focal and generalized seizures, whereas ANT stimulation may be best for focal seizures only. Studies have demonstrated that changes in stimulation-evoked response shape can be used as a biomarker for stimulation efficacy. Furthermore, new biomarkers have been identified that could be used for closed-loop stimulation. Improvements in patient screening and stimulation optimization are needed for patients to achieve optimal seizure control. Furthermore, therapy should be adjusted to suit individual patient needs. Recording evoked responses during the application of DBS could be used to measure the effectiveness of DBS and titrate stimulation as needed.

Efficacy and Tolerability of Perampanel as Adjunctive Therapy in Refractory Epilepsy (P3.5-020)

Efficacy and Tolerability of Perampanel as Adjunctive Therapy in Refractory Epilepsy (P3.5-020)

COMPARATIVE STUDY OF CLOBAZAM USED AS AN ADD ON THERAPY WITH PHENYTION AND CARBAMAZEPINE IN REFRACTORY EPILEPSY.

Refractory epilepsy is a failure of two (2) appropriately used anti epileptics (AED). This study Is a comparative study of clobzam use as add on with phenytoin and carbarnazepine.&#x0D; Aims &amp; Objectives: Aim of this study is to know how much Clobazam is effective as add on therapy in refractory epilepsy.&#x0D; Material and Methods: In this study two refractory groups of epilepsy are selected. group - 1 is refractory with phenytoin and Group-II with Carbamazepine. Clobazam(10mg) was added to both refractory groups and follow up For 3 Years.&#x0D; Results: There is significant reduction in seizure frequency after addition of clobazam in both refractory groups and 25% Patients were becomes completely seizure free.&#x0D; Discussion: This study was conducted in ANMMCH, Gaya Patients were selected from both outdoor &amp; Indoor of Medicine department and found 77.16% reduction in seizure frequency in group —I i;e with phenytoin and clobazam 78.16% in Group-II z;e with carbamazepine and clobazam and 25% Patients becomes completely seizure free.&#x0D; Conclusion: Clobazam is a very effective and safe AED for add on Therapy.&#x0D; Keywords: Refractory epilepsy Add on therapy mean seizure frequency

Cervical vagal nerve stimulation impairs glucose tolerance and suppresses insulin release in conscious rats.

Previously, we reported that cervical vagal nerve stimulation (VNS) increases blood glucose levels and inhibits insulin secretion in anesthetized rats through afferent signaling. Since afferent signaling is also thought to mediate the therapeutic effects of VNS in patients with therapy‐refractory epilepsy and major depression, the question arises if patients treated with VNS develop impaired glucose tolerance. Thus, we hypothesized that cervical VNS impairs glucose tolerance in conscious rats. Rats (n = 7) were instrumented with telemetric blood pressure sensors and right‐ or left‐sided cervical vagal nerve stimulators (3 V, 5 Hz, 1 msec pulse duration, 1 h on 1 h off). Glucose tolerance tests (GTTs, 1.5 g dextrose/kg BW, i.p.) were performed after overnight fasting with the stimulators on or off (sham stimulation) in randomized order separated by 3–4 days. Overnight VNS did not alter mean levels of blood pressure or heart rate, but increased fasted blood glucose levels (140 ± 13 mg/dL vs. 109 ± 8 mg/dL, P < 0.05). The area under the blood glucose concentration curves of the GTTs was larger during VNS than sham stimulation (3499 ± 211 mg/dL*h vs. 1810 ± 234 mg/dL*h, P < 0.05). One hour into the GTTs, the serum insulin concentrations had decreased during VNS (−0.57 ± 0.25 ng/mL, P < 0.05) and increased during sham stimulation (+0.71 ± 0.15 ng/mL, P < 0.05) compared to the fasted baseline levels. These results demonstrate that chronic cervical VNS elevates fasted blood glucose levels and impairs glucose tolerance likely through inhibition of glucose‐induced insulin release in conscious rats. It remains to be determined if patients treated with VNS are at greater risk of developing glucose intolerance and type 2 diabetes.

Early vagal nerve stimulator implantation in children: personal experience and review of the literature.

Data concerning the benefit of vagal nerve stimulation (VNS) in children under the age of 12years is sparse. It was shown that reduction of seizure frequency and duration at an early age could lead to better psychomotor development. We therefore compare the outcome between early (≤ 5years of age) and late (> 5years of age) implantation of VNS in children. This study is a prospective review of patients analyzing primarily the reduction of seizure frequency and secondarily epilepsy outcome assessed by the McHugh and Engel classification, reduction of antiepileptic drugs (AED), psychomotor development measured by the Vineland Adaptive Behavior Scale (VABS), and quality of life using the caregiver impression (CGI) scale. Mean follow-up time was 36 and 31months in the early and late group, respectively. Out of 12 consecutive VNS implantations for therapy refractory epilepsy, 5 were early implantations and 7 late implantations. Reduction of seizure frequency, McHugh and Engel classification, quality of life, psychomotor development and reduction of AED were comparable in both groups. One patient in the late group suffered from a postoperative infection resulting in explanation of the VNS device and re-implantation on the opposite side, while mortality rate was 0%. VNS seems to be a safe and feasible therapy in children even under the age of 5years. Responder rate, quality of life, and psychomotor development do not seem to be influenced by the child's age at implantation; however, larger studies analyzing the outcome of early VNS implantation are warranted.

Spotlight on the August 15 issue

#### Notable in Neurology This issue features an article that explicates a genetic syndrome that combines myasthenic features and severe neurodegeneration with therapy-refractory epilepsy and another that identifies seizure semiology in children with absence epilepsy. A featured Views & Reviews article discusses the effects of exercise interventions on fitness, cardiometabolic health, and bone health in adults with spinal cord injury. ### Automatic measurement of prosody in behavioral variant FTD An automated speech analysis method can aid clinicians in diagnosing and monitoring patients with behavioral variant frontotemporal dementia (bvFTD). The authors …

Development and pilot testing of a parent-reported health-related quality of life measure for children on the ketogenic diet: The KetoQoL.

The aim of the present study was to develop a parent-reported tool that will measure health-related quality of life (HRQoL) in children following ketogenic diet (KD) therapies for refractory epilepsy once it has been pilot tested and analysed. Parents of children following KD therapies for epilepsy were recruited through a public hospital in Queensland, Australia, in 2012 and 2014. Qualitative semistructured interviews were conducted in 2012 with 13 parents who described changes seen in their child's HRQoL while on the KD. A quality of life tool (QoL) was developed by adapting the Quality of Life in Childhood Epilepsy tool based on results and themes analysed from the interviews. The KetoQoL was pilot tested with 18 parents recruited in 2014. Interrelationships between variables and questions were explored with exploratory factor analysis (EFA) to determine which questions had the greatest effect on QoL. The first iteration of the KetoQoL consisted of five main domains: physical, cognitive, social, intrapersonal and effects on the family. The domains were subdivided into 18 variables, totalling 54 items. EFA demonstrated that items from the physical and effects on the family domains had the greatest effect on QoL. KetoQoL is an HRQoL tool developed using a range of methods and assessed for both face and content validity. Further testing of KetoQoL is required to refine and confirm the factors. This work will enhance the evaluation of treatment effectiveness in children with epilepsy following the KD.

Design and Synthesis of New Selective P-gp Substrates and Inhibitors

P-glycoprotein is an ATP-binding cassette transporter involved in drug absorption, distribution and excretion. It pumps a wide range of xenobiotic compounds out of the cells and plays a crucial role in Multi Drug Resistance. Moreover, recent studies have demonstrated that changes in P-gp function and/or expression at the blood brain barrier are implicated in the pathogenesis of neurological disorders such as therapy-refractory epilepsy, Alzheimer's and Parkinson's disease. In the last decades the studies have been addressed to the discovery of potent P-gp inhibitors able to revert pharmacoresistance and to the development of PET tracers to detect P-gp activity and expression for an early diagnosis and therapy monitoring of neurodegenerative disease. However, clinical trials have reported only limited success in reversing MDR and radiolabeled ligands were not actually useful to study differences of transporter function in different brain regions due to their low brain uptake. The difficulties into the discovery of new ligands is due to the use of different experimental assays, to the fact that P-gp is highly flexible protein with different binging sites and available crystallographic structures for the protein have inadequate resolution. To overcome these limitations research groups prefer computational approaches such as homology models in their structure-based design or ligand-based methodologies. A recent approach aimed to identify ligands which can interrupt ATP-binding and hydrolysis by P-gp, by interacting at the NBDs of the protein. In this review results from radiolabeled, substrates and inhibitors, for monitoring the activity and expression of P-gp, respectively, are presented.

Clobazam higher-evening differential dosing as an add-on therapy in refractory epilepsy

PurposeClobazam treatment tailored to the timing of patient's seizures may improve seizure control. We aim to describe the safety and efficacy of higher-evening differential dose of clobazam as add-on therapy in patients with night-time/early morning seizures. MethodDifferential dosing with higher evening dosing was started based on a high proportion of seizures (>80%) at nighttime (6p.m. to 6a.m.). Differential dosing was defined as providing more than 50% of the total daily dose of clobazam after 6p.m. ResultsTwenty-seven patients were treated with clobazam differential dosing as an add-on therapy. The median age was 9.1 years, with 11 (40.7%) females and median of the first follow-up was 2.7 months. Patients with differential dosing tolerated a higher median total clobazam dose of 0.8mg/kg/d at first follow-up, as compared to 0.6mg/kg/d in controls. In differential dose, the median percentage of the total clobazam dose administered in the evening was 66.7%. Differential dose patients exhibited a median seizure reduction of 75% as compared to 50% in controls (p<0.005). Patients with generalized seizures benefited the most from differential dosing with a 77.5% median seizure reduction, as compared to 50% in controls (p=0.017). ConclusionHigher-evening differential dose of clobazam improved seizure control in patients with predominantly nighttime and early-morning seizures. Chronotherapy tailored to the patients’ seizure susceptibility patterns may improve care in epilepsy patients as differential dosing may allow for higher overall treatment doses at times of greatest seizure susceptibility without increased side effects at other times.

LRP12 silencing during brain development results in cortical dyslamination and seizure sensitization

Correct positioning and differentiation of neurons during brain development is a key precondition for proper function. Focal cortical dysplasias (FCDs) are increasingly recognized as causes of therapy refractory epilepsies. Neuropathological analyses of respective surgical specimens from neurosurgery for seizure control often reveal aberrant cortical architecture and/or aberrantly shaped neurons in FCDs. However, the molecular pathogenesis particularly of FCDs with aberrant lamination (so-called FCD type I) is largely unresolved. Lipoproteins and particularly low-density lipoprotein receptor-related protein 12 (LRP12) are involved in brain development. Here, we have examined a potential role of LRP12 in the pathogenesis of FCDs. In vitro knockdown of LRP12 in primary neurons results in impaired neuronal arborization. In vivo ablation of LRP12 by intraventricularly in utero electroporated shRNAs elicits cortical maldevelopment, i.e. aberrant lamination by malpositioning of upper cortical layer neurons. Subsequent epilepsy phenotyping revealed pentylenetetrazol (PTZ)-induced seizures to be aggravated in cortical LRP12-silenced mice. Our data demonstrates IUE mediated cortical gene silencing as an excellent approach to study the role of distinct molecules for epilepsy associated focal brain lesions and suggests LRP12 and lipoprotein homeostasis as potential molecular target structures for the emergence of epilepsy-associated FCDs.

Commentary: Breaking down the barriers to using dietary therapy for refractory epilepsy.

Commentary: Breaking down the barriers to using dietary therapy for refractory epilepsy.

Copy number variations in children with brain malformations and refractory epilepsy.

Brain malformations are a major cause of therapy-refractory epilepsy as well as neurological and developmental disabilities in children. This study examined the frequency and the nature of copy number variations among children with structural brain malformations and refractory epilepsy. The medical records of all children born between 1990 and 2009 in the epilepsy registry at the Astrid Lindgren's Children's Hospital were reviewed and 86 patients with refractory epilepsy and various brain malformations were identified. Array-CGH analysis was performed in 76 of the patients. Pathogenic copy number variations were detected in seven children (9.2%). In addition, rearrangements of unclear significance, but possibly pathogenic, were detected in 11 (14.5%) individuals. In 37 (48.7%) patients likely benign, but previously unreported, copy number variants were detected. Thus, a large proportion of our patients had at least one rare copy number variant. Our results suggest that array-CGH should be considered as a first line genetic test for children with cerebral malformations and refractory epilepsy unless there is a strong evidence for a specific monogenic syndrome.

The role of drug combinations in therapy of refractory epilepsy—Clinical observations

The role of drug combinations in therapy of refractory epilepsy—Clinical observations

Visual fMRI under General Anaesthesia in Children with Therapy Refractory Epilepsies

Introduction: Assessment of the visual field is an integral part of the clinical neurological examination of children with therapy refractory epilepsies. Especially in the field of epilepsy surgery, the evaluation of any preoperatively existing visual field defects is important with regards to surgical planning and the risk estimation of additional postoperative deficits. However, performing a formal perimetry or a clinical visual field examination using confrontation techniques is often not possible in children with therapy refractory epilepsies due to young age of the patients, cognitive impairment, or lack of cooperation. We report first experience with visual functional magnetic resonance imaging (fMRI) examinations under general anesthesia.

Blood–brain barrier P-glycoprotein activity in patients with therapy-refractory epilepsy before and after surgical focal resection assessed with (R)-[11C]verapamil and positron emission tomography

Blood–brain barrier P-glycoprotein activity in patients with therapy-refractory epilepsy before and after surgical focal resection assessed with (R)-[11C]verapamil and positron emission tomography