SCN1A, encoding the alpha 1 subunit of the sodium channel, is associated with several epilepsy syndromes and a range of other diseases. SCN1A represents the archetypal channelopathy associated with a ...wide phenotypic spectrum of epilepsies ranging from genetic epilepsy with febrile seizures plus (GEFS+), to developmental and epileptic encephalopathies (DEEs). SCN1A disorders also result in other diseases such as hemiplegic migraine and autism spectrum disorder (ASD). Dravet syndrome (DS) is the prototypic DEE with an early onset of febrile status epilepticus, hemiclonic or generalized tonic‐clonic seizures, and later onset of additional seizure types. Electroencephalography (EEG) and magnetic resonance imaging (MRI) are normal at onset. Development is normal in the first year of life but plateaus rapidly, with most patients ultimately having intellectual disability. Epilepsy is drug‐resistant and necessitates polytherapy. Most pathogenic variants occur de novo in the affected child, but they are inherited from mosaic affected or unaffected parents in rare cases. The molecular finding of haploinsufficiency is consistent with a loss‐of‐function defect in cells and animal models. Although seizures are the most commonly reported symptom in DS, many additional issues critically affect patients’ cognitive and behavioral functioning. Hemiplegic migraine (HM) is a rare form of migraine with aura, characterized by the emergence of hemiparesis as part of the aura phase. All SCN1A mutations reported in sporadic/familial HM3 are missense mutations. Most of the experimental results show that they cause a gain of function of NaV1.1 as opposed to the loss of function of the epileptogenic NaV1.1 mutations. SCN1A and SCN2A pathogenic variants have been identified in genetic studies of cohorts of patients with ASD. In addition, ASD features are often reported in patients with Dravet syndrome and other DEEs.
Summary
Idiopathic hemiconvulsion hemiplegia and epilepsy syndrome (IHHE) and febrile infection–related epilepsy syndrome (FIRES) are rare epileptic syndromes characterized by the occurrence of ...status epilepticus in a previously healthy child during or closely after a febrile episode. In both syndromes, there is no evidence of central nervous system infection (encephalitis) and the etiology remains unclear. Treatment is disappointing, particularly in FIRES, except for a response to ketogenic diet (KD) in half of patients. In IHHS, children develop hemispheric brain atrophy with contralateral hemiplegia, epilepsy, and a variable degree of cognitive deficit. Patients with FIRES develop refractory epilepsy with severe cognitive deficit affecting the temporal and frontal lobe functions. The role of inflammation is hypothesized with a vicious circle involving inflammation and seizure activity facilitated by brain maturation putting them under the concept of “acute encephalopathy with inflammation‐mediated status epilepticus.”
The Dravet syndrome is a complex childhood epilepsy disorder that is associated with drug-resistant seizures and a high mortality rate. We studied cannabidiol for the treatment of drug-resistant ...seizures in the Dravet syndrome.
In this double-blind, placebo-controlled trial, we randomly assigned 120 children and young adults with the Dravet syndrome and drug-resistant seizures to receive either cannabidiol oral solution at a dose of 20 mg per kilogram of body weight per day or placebo, in addition to standard antiepileptic treatment. The primary end point was the change in convulsive-seizure frequency over a 14-week treatment period, as compared with a 4-week baseline period.
The median frequency of convulsive seizures per month decreased from 12.4 to 5.9 with cannabidiol, as compared with a decrease from 14.9 to 14.1 with placebo (adjusted median difference between the cannabidiol group and the placebo group in change in seizure frequency, -22.8 percentage points; 95% confidence interval CI, -41.1 to -5.4; P=0.01). The percentage of patients who had at least a 50% reduction in convulsive-seizure frequency was 43% with cannabidiol and 27% with placebo (odds ratio, 2.00; 95% CI, 0.93 to 4.30; P=0.08). The patient's overall condition improved by at least one category on the seven-category Caregiver Global Impression of Change scale in 62% of the cannabidiol group as compared with 34% of the placebo group (P=0.02). The frequency of total seizures of all types was significantly reduced with cannabidiol (P=0.03), but there was no significant reduction in nonconvulsive seizures. The percentage of patients who became seizure-free was 5% with cannabidiol and 0% with placebo (P=0.08). Adverse events that occurred more frequently in the cannabidiol group than in the placebo group included diarrhea, vomiting, fatigue, pyrexia, somnolence, and abnormal results on liver-function tests. There were more withdrawals from the trial in the cannabidiol group.
Among patients with the Dravet syndrome, cannabidiol resulted in a greater reduction in convulsive-seizure frequency than placebo and was associated with higher rates of adverse events. (Funded by GW Pharmaceuticals; ClinicalTrials.gov number, NCT02091375 .).
Over the last decade, advances in genetics, neuroimaging and EEG have enabled the aetiology of epilepsy to be identified earlier in the disease course than ever before. At the same time, progress in ...the study of experimental models of epilepsy has provided a better understanding of the mechanisms underlying the condition and has enabled the identification of therapies that target specific aetiologies. We are now witnessing the impact of these advances in our daily clinical practice. Thus, now is the time for a paradigm shift in epilepsy treatment from a reactive attitude, treating patients after the onset of epilepsy and the initiation of seizures, to a proactive attitude that is more broadly integrated into a 'P4 medicine' approach. This P4 approach, which is personalized, predictive, preventive and participatory, puts patients at the centre of their own care and, ultimately, aims to prevent the onset of epilepsy. This aim will be achieved by adapting epilepsy treatments not only to a given syndrome but also to a given patient and moving from the usual anti-seizure treatments to personalized treatments designed to target specific aetiologies. In this Review, we present the current state of this ongoing revolution, emphasizing the impact on clinical practice.
Over time, with careful delineation of Dravet syndrome, we have gained experience in treatments most likely to lead to improvement in seizures, as well as those that should be avoided. Sodium ...valproate, clobazam, stiripentol, and topiramate are all medications that may lead to benefit, as well as the ketogenic diet. Bromides may be utilized in resistant cases. However, equally important are outlining prompt rescue treatment for prolonged seizures and avoidance of precipitants. Newer agents including cannabidiol and fenfluramine have been demonstrated to be of benefit in clinical trials. We propose an algorithm for management, but appreciate that the positioning of newer agents is yet to be established.
Summary Background Everolimus, a mammalian target of rapamycin (mTOR) inhibitor, has been used for various benign tumours associated with tuberous sclerosis complex. We assessed the efficacy and ...safety of two trough exposure concentrations of everolimus, 3–7 ng/mL (low exposure) and 9–15 ng/mL (high exposure), compared with placebo as adjunctive therapy for treatment-resistant focal-onset seizures in tuberous sclerosis complex. Methods In this phase 3, randomised, double-blind, placebo-controlled study, eligible patients aged 2–65 years with tuberous sclerosis complex and treatment-resistant seizures (≥16 in an 8-week baseline phase) receiving one to three concomitant antiepileptic drugs were recruited from 99 centres across 25 countries. Participants were randomly assigned (1:1:1), via permuted-block randomisation (block size of six) implemented by Interactive Response Technology software, to receive placebo, low-exposure everolimus, or high-exposure everolimus. Randomisation was stratified by age subgroup (<6 years, 6 to <12 years, 12 to <18 years, and ≥18 years). Patients, investigators, site personnel, and the sponsor's study team were masked to treatment allocation. The starting dose of everolimus depended on age, body-surface area, and concomitant use of cytochrome 3A4/P-glycoprotein inducers. Dose adjustments were done to attain target trough ranges during a 6-week titration period, and as needed during a 12-week maintenance period of core phase. Patients or their caregivers recorded events in a seizure diary throughout the study. The primary endpoint was change from baseline in the frequency of seizures during the maintenance period, defined as response rate (the proportion of patients achieving ≥50% reduction in seizure frequency) and median percentage reduction in seizure frequency, in all randomised patients. This study is registered with ClinicalTrials.gov , number NCT01713946. Findings Between July 3, 2013, and May 29, 2015, 366 patients were enrolled and randomly assigned to placebo (n=119), low-exposure everolimus, (n=117), or high-exposure everolimus (n=130). The response rate was 15·1% with placebo (95% CI 9·2–22·8; 18 patients) compared with 28·2% for low-exposure everolimus (95% CI 20·3–37·3; 33 patients; p=0·0077) and 40·0% for high-exposure everolimus (95% CI 31·5–49·0; 52 patients; p<0·0001). The median percentage reduction in seizure frequency was 14·9% (95% CI 0·1–21·7) with placebo versus 29·3% with low-exposure everolimus (95% CI 18·8–41·9; p=0·0028) and 39·6% with high-exposure everolimus (95% CI 35·0–48·7; p<0·0001). Grade 3 or 4 adverse events occurred in 13 (11%) patients in the placebo group, 21 (18%) in the low-exposure group, and 31 (24%) in the high-exposure group. Serious adverse events were reported in three (3%) patients who received placebo, 16 (14%) who received low-exposure everolimus, and 18 (14%) who received high-exposure everolimus. Adverse events led to treatment discontinuation in two (2%) patients in the placebo group versus six (5%) in the low-exposure group and four (3%) in the high-exposure group. Interpretation Adjunctive everolimus treatment significantly reduced seizure frequency with a tolerable safety profile compared with placebo in patients with tuberous sclerosis complex and treatment-resistant seizures. Funding Novartis Pharmaceuticals Corporation.
Summary
We report the proceedings of the First International new‐onset refractory status epilepticus (NORSE) and febrile infection‐related epilepsy syndrome (FIRES) Symposium. To promote awareness of ...this condition and foster research efforts, we conveyed the First International new‐onset refractory status epilepticus (NORSE) and febrile infection‐related epilepsy syndrome (FIRES) Symposium. The conference was supported by The NORSE Institute (http://www.norseinstitute.org). This article summarizes the discussions that were held during the Symposium and presents our strategy to unravel the cause of these disorders and to improve patient care. The standardized definitions for these disorders that have been developed, are required to improve communication and facilitate the development of multicenter registries and biobanks. A distinction between childhood‐ and adult‐onset forms of the syndrome is not supported by strong scientific evidence and it is argued that both should be studied together. Although the pathophysiology remains elusive, nascent evidence suggests a role for a postinfectious cytokine‐mediated mechanism, which should be further investigated. It also appears important to develop tools for their early recognition and prompt treatment. Recent evidence suggests that specific electroencephalography (EEG) features might be helpful. The optimal treatment options remain to be determined; immune therapies are usually disappointing, but the ketogenic diet has proved effective in uncontrolled trials. NORSE and FIRES represent a very delicate clinical situation with specific communication issues between physicians and with patients and families. Standardized consensus definitions and a multidisciplinary multicenter strategy will help research efforts and improve clinical care for patients with NORSE and FIRES.
Objective
This study was undertaken to gain consensus from experienced physicians and caregivers regarding optimal diagnosis and management of Dravet syndrome (DS), in the context of recently ...approved, DS‐specific therapies and emerging disease‐modifying treatments.
Methods
A core working group was convened consisting of six physicians with recognized expertise in DS and two representatives of the Dravet Syndrome Foundation. This core group summarized the current literature (focused on clinical presentation, comorbidities, maintenance and rescue therapies, and evolving disease‐modifying therapies) and nominated the 31‐member expert panel (ensuring international representation), which participated in two rounds of a Delphi process to gain consensus on diagnosis and management of DS.
Results
There was strong consensus that infants 2–15 months old, presenting with either a first prolonged hemiclonic seizure or first convulsive status epilepticus with fever or following vaccination, in the absence of another cause, should undergo genetic testing for DS. Panelists agreed on evolution of specific comorbidities with time, but less agreement was achieved on optimal management. There was also agreement on appropriate first‐ to third‐line maintenance therapies, which included the newly approved agents. Whereas there was agreement for recommendation of disease‐modifying therapies, if they are proven safe and efficacious for seizures and/or reduction of comorbidities, there was less consensus for when these should be started, with caregivers being more conservative than physicians.
Significance
This International DS Consensus, informed by both experienced global caregiver and physician voices, provides a strong overview of the impact of DS, therapeutic goals and optimal management strategies incorporating the recent therapeutic advances in DS, and evolving disease‐modifying therapies.
Summary
We convened an international group of experts to standardize definitions of New‐Onset Refractory Status Epilepticus (NORSE), Febrile Infection‐Related Epilepsy Syndrome (FIRES), and related ...conditions. This was done to enable improved communication for investigators, physicians, families, patients, and other caregivers. Consensus definitions were achieved via email messages, phone calls, an in‐person consensus conference, and collaborative manuscript preparation. Panel members were from 8 countries and included adult and pediatric experts in epilepsy, electroencephalography (EEG), and neurocritical care. The proposed consensus definitions are as follows: NORSE is a clinical presentation, not a specific diagnosis, in a patient without active epilepsy or other preexisting relevant neurological disorder, with new onset of refractory status epilepticus without a clear acute or active structural, toxic or metabolic cause. FIRES is a subcategory of NORSE, applicable for all ages, that requires a prior febrile infection starting between 2 weeks and 24 hours prior to onset of refractory status epilepticus, with or without fever at onset of status epilepticus. Proposed consensus definitions are also provided for Infantile Hemiconvulsion‐Hemiplegia and Epilepsy syndrome (IHHE) and for prolonged, refractory and super‐refractory status epilepticus. This document has been endorsed by the Critical Care EEG Monitoring Research Consortium. We hope these consensus definitions will promote improved communication, permit multicenter research, and ultimately improve understanding and treatment of these conditions.
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