Efficacy of cannabidiol in convulsive and nonconvulsive seizure types associated with treatment-resistant epilepsies in the Expanded Access Program.

The cannabidiol (CBD) Expanded Access Program (EAP), initiated in 2014, provided CBD (Epidiolex) to patients with treatment-resistant epilepsy (TRE). In the final pooled analysis of 892 patients treated through January 2019 (median exposure = 694 days), CBD treatment was associated with a 46%-66% reduction in median monthly total (convulsive plus nonconvulsive) seizure frequency. CBD was well tolerated, and adverse events were consistent with previous findings. We used pooled EAP data to investigate the effectiveness of add-on CBD therapy for individual convulsive seizure types (clonic, tonic, tonic-clonic, atonic, focal to bilateral tonic-clonic), nonconvulsive seizure types (focal with and without impaired consciousness, absence [typical and atypical], myoclonic, myoclonic absence), and epileptic spasms. CBD treatment was associated with a reduction in the frequency of convulsive seizure types (median percentage reduction = 47%-100%), and nonconvulsive seizure types and epileptic spasms (median percentage reduction = 50%-100%) across visit intervals through 144 weeks of treatment. Approximately 50% of patients had ≥50% reduction in convulsive and nonconvulsive seizure types and epileptic spasms at nearly all intervals. These results show a favorable effect of long-term CBD use in patients with TRE, who may experience various convulsive and nonconvulsive seizure types. Future controlled trials are needed to confirm these findings.

Intraoperative Cortical Asynchrony Predicts Abnormal Postoperative Electroencephalogram.

BACKGROUND: Postoperative electroencephalograms (EEGs) can identify seizure activity and neurologic dysfunction in high-risk neonates requiring cardiac surgical procedures. Although intraoperative EEG monitoring is uncommon, variations in cerebral blood flow and temperature during antegrade cerebral perfusion (ACP) can manifest as cortical asynchrony during EEG monitoring. We hypothesized that intraoperative EEG cortical asynchrony would identify neonates at risk for abnormal postoperative EEG tracings. METHODS: Neonates requiring ACP for cardiac repair or palliation had continuous baseline, intraoperative, and postoperative hemodynamic and EEG monitoring. Synchronous and asynchronous cortical bursts were quantified during (1) cooling before ACP, (2) ACP, and (3) rewarming. Asynchronous bursts were defined as interhemispheric variations in electrical voltage or frequency. Neonates were divided into 2 groups, those with and without an abnormal postoperative EEG, which was defined as either persistent asynchrony for more than 2 hours or seizure activity on EEG. RESULTS: Among 40 neonates, 296 asynchronous bursts were noted, most commonly during rewarming. Eight (20%) neonates had an abnormal postoperative EEG (seizure activity, n = 3; persistent asynchrony, n = 5). Baseline demographics and intraoperative hemodynamics were similar between the groups. However, the total number of intraoperative asynchronous bursts was greater in neonates with an abnormal postoperative EEG (17 [11, IQR:24] vs 3 [IQR:1, 7]; P < .001). Multivariate analysis confirmed that the number of asynchronous bursts was independently associated with an abnormal postoperative EEG (odds ratio,1.35; confidence interval,:1.10, 1.65; P = .004). CONCLUSIONS: Neonates with a greater number of intraoperative asynchronous cortical bursts had an abnormal postoperative EEG.

Neurodevelopmental Delay After the Neonatal Repair of Coarctation and Arch Obstruction.

BACKGROUND: Although single ventricle physiology and cyanosis are known risk factors for neurodevelopmental delay (NDD), the impacts of isolated coarctation (Iso CoA) repair or arch reconstruction (AR) are less understood. METHODS: The Vineland Adaptive Behavior Scales, third edition, prospectively evaluated children without a genetic syndrome. An overall composite score, normalized to age and sex, was generated from individual domain scores. NDD was defined as a composite or domain score at least 1 SD less than the established mean. Iso CoA was repaired using a left thoracotomy, whereas AR was performed using a sternotomy and cardiopulmonary bypass. Children with a structurally normal heart and without previous surgery were used as control patients. RESULTS: Of 60 children, 50 required neonatal repair (12 for Iso CoA, 38 for AR), and 10 were control patients. From the entire cohort of children who required neonatal coarctation repair (Iso CoA + AR) composite (93.9 ± 15.9 vs 105.0 ± 7.4; P = .004) and all domain scores were significantly lower than control patients. NDD was present in 25 of 50 children after repair and in 0 of 10 control patients (P = .003). Similarly, the prevalence of NDD was significantly greater after Iso CoA repair (58.3% vs 0%; P = .005) and AR (47.3% vs 0%; P = .007) than in the control population, but no significant difference was found between the Iso CoA and AR groups (P = .74). CONCLUSIONS: In this small cohort, half of the neonates who required either Iso CoA repair or AR exhibit NDD at an intermediate-term follow-up.

Long-term safety and efficacy of cannabidiol in children and adults with treatment resistant Lennox-Gastaut syndrome or Dravet syndrome: Expanded access program results.

BACKGROUND: Since 2014, patients with severe treatment-resistant epilepsies (TREs) have been receiving add-on cannabidiol (CBD) in an ongoing, expanded access program (EAP), which closely reflects clinical practice. We conducted an interim analysis of long-term efficacy and tolerability in patients with Lennox-Gastaut syndrome (LGS) or Dravet syndrome (DS) who received CBD treatment through December 2016. METHODS: Children and adults with LGS/DS taking stable doses of antiepileptic drugs (AEDs) at baseline were included from 25 EAP sites across the United States. During the 4-week baseline period, parents/caregivers kept diaries of all countable seizure types. Patients received a pharmaceutical formulation of highly purified CBD (Epidiolex®; 100 mg/mL) in oral solution at 2-10 mg/kg/day, titrated until tolerability limit or a maximum dose of 25-50 mg/kg/day. Patient visits were every 2-4 weeks. The percentage change from baseline in median monthly convulsive (ie, major motor) and total seizures was evaluated at 12-week intervals through 96 weeks. The percentages of patients who had ≥50%, ≥75%, and 100% reduction in monthly seizures relative to the baseline period were also evaluated. Adverse events (AEs) were monitored and summarized for the safety analysis set (SAS) through 144 weeks. RESULTS: Of the 607 patients in the SAS, 58 had DS and 94 had LGS (N = 152); 455 patients had other TREs. Twenty-eight percent of LGS/DS patients withdrew, primarily owing to lack of efficacy (20%). LGS/DS patients were taking a median of 3 (0-10) concomitant AEDs. Median treatment duration was 78.3 (range, 4.1-146.4) weeks. Between weeks 12 and 96, median CBD dose ranged from 21 to 25 mg/kg/day. At 12 weeks, add-on CBD reduced median monthly major motor seizures by 50% and total seizures by 44%, with consistent reductions in both seizure types through 96 weeks. At 12 weeks, the proportions of patients with ≥50%, ≥75%, and 100% reductions in major motor seizures were 53%, 23%, and 6%; the proportions with corresponding reductions in total seizures were 46%, 26%, and 5%. Responder rates for both seizure types were consistent through 96 weeks. CBD had an acceptable safety profile; the most common AEs were somnolence (30%) and diarrhea (24%). CONCLUSIONS: Results from this interim analysis support add-on CBD as an effective long-term treatment option in LGS or DS.

Open-label use of highly purified CBD (Epidiolex®) in patients with CDKL5 deficiency disorder and Aicardi, Dup15q, and Doose syndromes.

OBJECTIVE: We studied our collective open-label, compassionate use experience in using cannabidiol (CBD) to treat epilepsy in patients with CDKL5 deficiency disorder and Aicardi, Doose, and Dup15q syndromes. METHODS: We included patients aged 1-30 years with severe childhood-onset epilepsy who received CBD for ≥10 weeks as part of multiple investigator-initiated expanded access or state access programs for a compassionate prospective interventional study: CDKL5 deficiency disorder (n = 20), Aicardi syndrome (n = 19), Dup15q syndrome (n = 8), and Doose syndrome (n = 8). These patients were treated at 11 institutions from January 2014 to December 2016. RESULTS: The percent change in median convulsive seizure frequency for all patients taking CBD in the efficacy group decreased from baseline [n = 46] to week 12 (51.4% [n = 35], interquartile range (IQR): 9-85%) and week 48 (59.1% [n = 27], IQR: 14-86%). There was a significant difference between the percent changes in monthly convulsive seizure frequency during baseline and week 12, χ2(2) = 22.9, p = 0.00001, with no difference in seizure percent change between weeks 12 and 48. Of the 55 patients in the safety group, 15 (27%) withdrew from extended observation by week 144: 4 due to adverse effects, 9 due to lack of efficacy, 1 withdrew consent, and 1 was lost to follow-up. SIGNIFICANCE: This open-label drug trial provides class III evidence for the long-term safety and efficacy of CBD administration in patients with treatment-resistant epilepsy (TRE) associated with CDKL5 deficiency disorder and Aicardi, Dup15q, and Doose syndromes. Adjuvant therapy with CBD showed similar safety and efficacy for these four syndromes as reported in a diverse population of TRE etiologies. This study extended analysis of the prior report from 12 weeks to 48 weeks of efficacy data and suggested that placebo-controlled randomized trials should be conducted to formally assess the safety and efficacy of CBD in these epileptic encephalopathies.

PLXNA1 developmental encephalopathy with syndromic features: A case report and review of the literature.

Developmental encephalopathies constitute a broad and genetically heterogeneous spectrum of disorders associated with global developmental delay, intellectual disability, frequent epilepsy, and other neurofunctional abnormalities. Here, we report a male presenting with infantile onset epilepsy and syndromic features resembling Dubowitz syndrome identified to have a de novo PLXNA1 variant by whole exome sequencing. This constitutes the second report of PLXNA1 sequence variation associated with early onset epilepsy, and the first to expand on the clinical features of this emerging disorder. This reports suggests that nonsynonymous de novo sequence variations in PLXNA1 are associated with a novel human phenotype characterized by intractable early onset epilepsy, intellectual disability, and syndromic features.

Developing a novel epileptic discharge localization algorithm for electroencephalogram infantile spasms during hypsarrhythmia.

Infantile spasms (ISS) is a devastating epileptic syndrome that affects children under the age of 1 year. The diagnosis of ISS is based on the semiology of the seizure and the electroencephalogram (EEG) background characterized by hypsarrhythmia (HYPS). However, even skilled electrophysiologists may interpret the EEG of children with ISS differently, and commercial software or existing epilepsy detection algorithms are not helpful. Since EEG is a key factor in the diagnosis of ISS, misinterpretation could result in serious consequences including inappropriate treatment. In this paper, we developed a novel algorithm to localize the relevant electrical abnormality known as epileptic discharges (or spikes) to provide a quantitative assessment of ISS in HYPS. The proposed algorithm extracts novel time-frequency features from the EEG signals and localizes the epileptic discharges associated with ISS in HYPS using a support vector machine classifier. We evaluated the proposed method on an EEG dataset with ISS subjects and obtained an average true positive and false negative of 98 and 7%, respectively, which was a significant improvement compared to the results obtained using the clinically available software. The proposed automated method provides a quantitative assessment of ISS in HYPS, which could significantly enhance our knowledge in therapy management of ISS.

Phenotype Differentiation of FOXG1 and MECP2 Disorders: A New Method for Characterization of Developmental Encephalopathies.

OBJECTIVE: To differentiate developmental encephalopathies by creating a novel quantitative phenotyping tool. STUDY DESIGN: We created the Developmental Encephalopathy Inventory (DEI) to differentiate disorders with complex multisystem neurodevelopmental symptoms. We then used the DEI to study the phenotype features of 20 subjects with FOXG1 disorder and 11 subjects with MECP2 disorder. RESULTS: The DEI identified core domains of fine motor and expressive language that were severely impaired in both disorders. Individuals with FOXG1 disorder were overall more severely impaired. Subjects with FOXG1 disorder were less able to walk, had worse fine motor skills, more disability in receptive language and reciprocity, and had more disordered sleep than did subjects with MECP2 disorder (P <.05). Covariance, cluster, and principal component analysis confirmed a relationship between impaired awareness, reciprocity, and language in both disorders. In addition, abnormal ambulation was a first principal component for FOXG1 but not for MECP2 disorder, suggesting that impaired ambulation is a strong differentiating factor clinically between the 2 disorders. CONCLUSIONS: We have developed a novel quantitative developmental assessment tool for developmental encephalopathies and propose this tool as a method to identify and illustrate core common and differential domains of disability in these complex disorders. These findings demonstrate clear phenotype differences between FOXG1 and MECP2 disorders.

Neurodevelopmental outcomes after neonatal cardiac surgery: Role of cortical isoelectric activity.

OBJECTIVES: Neonates with congenital heart disease are at risk for impaired neurodevelopment after cardiac surgery. We hypothesized that intraoperative EEG activity may provide insight into future neurodevelopmental outcomes. METHODS: Neonates requiring surgery had continuous intraoperative EEG and hemodynamic monitoring. The level of EEG suppression was classified as either: slow and continuous; moderate burst suppression; severe burst suppression; or isoelectric (no brain activity for >3 minutes). Follow-up neurodevelopmental outcomes were assessed using the Vineland Adaptive Behavior Scale II (Vineland-II). RESULTS: Twenty-one neonates requiring cardiac surgery developed a slow and continuous EEG pattern after general anesthesia. Ten neonates (48%) maintained continuous brain electrical activity with moderate burst suppression as the maximum level of EEG suppression. Eleven neonates (52%) developed severe burst suppression that progressed into an isoelectric state during the deep hypothermic period required for circulatory arrest. However, the duration of this state was significantly longer than circulatory arrest times (111.1 ± 50 vs 22.3 ± 17 minutes; P < .001). At a mean follow-up at 5.6 ± 1.0 years, compared with neonates with continuous brain electrical activity, neonates who developed an isoelectric state had lower Vineland-II scores in communication. There was an inverse relationship between composite Vineland-II scores and duration of isoelectric activity (R = -0.75, P = .01). Of neonates who experienced an isoelectric state, durations of >90 minutes were associated with the lowest Vineland-II scores (125.0 ± 2.6 vs 81.1 ± 12.7; P < .01). CONCLUSIONS: The duration of cortical isoelectric states seems related to neurodevelopmental outcomes. Strategies using continuous EEG monitoring to minimize isoelectric states may be useful during complex congenital heart surgery.

Characteristic Features of the Interictal EEG Background in 2 Patients With Malignant Migrating Partial Epilepsy in Infancy.

PURPOSE: To describe chronological electrographic features of the interictal EEG background observed in two patients with malignant migrating partial epilepsy in infancy from neonatal to early infantile period. METHODS: EEGs of two patients who fulfilled diagnostic criteria for malignant migrating partial epilepsy in infancy were acquired over the period of 6 months to monitor treatment efficacy and characterize seizures and other paroxysmal events. RESULTS: Both patients followed a similar sequential pattern. A distinctive evolution from a dysmature term neonatal EEG pattern to an asynchronous suppression burst pattern was observed before the interictal background becoming continuous. CONCLUSIONS: Physicians providing care to infants with intractable epilepsy and burst suppression EEG pattern should be alert to the possibility of malignant migrating partial epilepsy in infancy. An earlier diagnosis of malignant migrating partial epilepsy in infancy would help to guide diagnostic workup including genetic testing.

Automatic localization of epileptic spikes in eegs of children with infantile spasms.

A novel methodology is proposed for identifying epileptiform discharges associated with individuals exhibiting Infantile Spasms (ISS) also known as West Syndrome, which is characterized by electroencephalogram (EEG) recordings exhibiting hypsarrythmia (HYPS). The approach to identify these discharges consists of three stages: first - construct the time-frequency domain (TFD) of the EEG recording using matching pursuit TFD (MP-TFD), second - decompose the TFD matrix into two submatrices (W, H) using non-negative matrix factorization (NMF), and third - use the decomposed spectral and temporal vectors to locate the epileptiform discharges, referred to as spikes, during intervals of HYPS. The method was applied to an EEG dataset of five individuals and the identification of spike locations was compared with those which were visually identified by the epileptologists and those obtained using commercially available clinical analysis software. The MP-TFD method resulted in average true positive and false negative percentages of 86% and 14%, respectively, which represents a significant improvement over the clinical software, which achieved average true positive and false negative percentages of 4% and 96%, respectively.

Genetic disorders associated with postnatal microcephaly.

Several genetic disorders are characterized by normal head size at birth, followed by deceleration in head growth resulting in postnatal microcephaly. Among these are classic disorders such as Angelman syndrome and MECP2-related disorder (formerly Rett syndrome), as well as more recently described clinical entities associated with mutations in CASK, CDKL5, CREBBP, and EP300 (Rubinstein-Taybi syndrome), FOXG1, SLC9A6 (Christianson syndrome), and TCF4 (Pitt-Hopkins syndrome). These disorders can be identified clinically by phenotyping across multiple neurodevelopmental and neurobehavioral realms, and enough data are available to recognize these postnatal microcephaly disorders as separate diagnostic entities in their own right. A second diagnostic grouping, comprised of Warburg MICRO syndrome, Cockayne syndrome, and Cerebral-oculo-facial skeletal syndrome, share similar features of somatic growth failure, ophthalmologic, and dysmorphologic features. Many postnatal microcephaly syndromes are caused by mutations in genes important in the regulation of gene expression in the developing forebrain and hindbrain, although important synaptic structural genes also play a role. This is an emerging group of disorders with a fascinating combination of brain malformations, specific epilepsies, movement disorders, and other complex neurobehavioral abnormalities.

Epilepsy and outcome in FOXG1-related disorders.

OBJECTIVE: FOXG1-related disorders are associated with severe intellectual disability, absent speech with autistic features, and epilepsy. Children with deletions or intragenic mutations of FOXG1 also have postnatal microcephaly, morphologic abnormalities of the corpus callosum, and choreiform movements. Duplications of 14q12 often present with infantile spasms, and have subsequent intellectual disability with autistic features. Long-term epilepsy outcome and response to treatment have not been studied systematically in a well-described cohort of subjects with FOXG1-related disorders. We report on the epilepsy features and developmental outcome of 23 new subjects with deletions or intragenic mutations of FOXG1, and 7 subjects with duplications. METHODS: Subjects had either chromosomal microarray or FOXG1 gene sequencing performed as part of routine clinical care. Development and epilepsy follow-up data were collected from medical records from treating neurologists and through telephone parental interviews using standardized questionnaires. RESULTS: Epilepsy was diagnosed in 87% of the subjects with FOXG1-related disorders. The mean age of epilepsy diagnosis in FOXG1 duplications was significantly younger than those with deletions/intragenic mutations (p = 0.0002). All of the duplication FOXG1 children with infantile spasms responded to hormonal therapy, and only one required long-term antiepileptic therapy. In contrast, more children with deletions/intragenic mutations required antiepileptic drugs on follow-up (p < 0.0005). All subjects with FOXG1-related disorders had neurodevelopmental disabilities after 3 years of age, regardless of the epilepsy type or intractability of seizures. All had impaired verbal language and social contact, and three duplication subjects were formally diagnosed with autism. Subjects with deletion/intragenic mutations, however, had significantly worse ambulation (p = 0.04) and functional hand use (p < 0.0005). SIGNIFICANCE: Epilepsy and developmental outcome characteristics allow clinicians to distinguish among the FOXG1-related disorders. Further genotype-phenotype studies of FOXG1 may help to elucidate why children develop different forms of developmental epilepsy.

De novo mutations in the beta-tubulin gene TUBB2A cause simplified gyral patterning and infantile-onset epilepsy.

Tubulins, and microtubule polymers into which they incorporate, play critical mechanical roles in neuronal function during cell proliferation, neuronal migration, and postmigrational development: the three major overlapping events of mammalian cerebral cortex development. A number of neuronally expressed tubulin genes are associated with a spectrum of disorders affecting cerebral cortex formation. Such "tubulinopathies" include lissencephaly/pachygyria, polymicrogyria-like malformations, and simplified gyral patterns, in addition to characteristic extracortical features, such as corpus callosal, basal ganglia, and cerebellar abnormalities. Epilepsy is a common finding in these related disorders. Here we describe two unrelated individuals with infantile-onset epilepsy and abnormalities of brain morphology, harboring de novo variants that affect adjacent amino acids in a beta-tubulin gene TUBB2A. Located in a highly conserved loop, we demonstrate impaired tubulin and microtubule function resulting from each variant in vitro and by using in silico predictive modeling. We propose that the affected functional loop directly associates with the alpha-tubulin-bound guanosine triphosphate (GTP) molecule, impairing the intradimer interface and correct formation of the alpha/beta-tubulin heterodimer. This study associates mutations in TUBB2A with the spectrum of "tubulinopathy" phenotypes. As a consequence, genetic variations affecting all beta-tubulin genes expressed at high levels in the brain (TUBB2B, TUBB3, TUBB, TUBB4A, and TUBB2A) have been linked with malformations of cortical development.

Neonatal seizures in the era of therapeutic hypothermia: keeping it cool.

The neonatal brain is potentially wired for seizures based on the timing and severity of disease states in the context of vulnerabilities of the immature brain.(1) Seizures in neonates are often the presenting sign of potential brain injury from multiple etiologies, including asphyxia or hypoxic ischemic encephalopathy (HIE). Seizures may also result from diverse causes of neonatal encephalopathy, with those in the neonatal period portending a worse neurodevelopmental prognosis if associated with damage to the developing brain.(2) The diagnosis of seizures in the neonatal population, however, can be challenging. Seizures are often subtle; they may be associated with autonomic symptoms or fail to display clinical manifestations coincident with electrographic seizures.(3.)

Intraoperative electroencephalography predicts postoperative seizures in infants with congenital heart disease.

BACKGROUND: During the surgical repair of infants with congenital cardiac defects, there can be periods of decreased cerebral blood flow, particularly during deep hypothermic circulatory arrest. As a result, these infants are at increased risk for seizures and long-term neurodevelopmental difficulties. METHODS: Thirty-two infants with congenital heart disease had continuous video-electroencephalographic (EEG) monitoring pre-, intra-, and postoperatively for 48 hours after surgery. RESULTS: For patients requiring deep hypothermic circulatory arrest (n = 17) the EEG pattern for all patients became suppressed and eventually isoelectric below 25 °C. Two of the 32 infants had electrical seizures within the 48-hour monitoring period. Both required deep hypothermic circulatory arrest, and the burst pattern during recovery had rhythmic, sharp components that were high amplitude and often asynchronous between the hemispheres. The interval between the onset of seizure activity and initiation of the sharp burst pattern during surgery was 29 and 40 hours. This pattern was not observed during isoelectric recovery from infants who did not develop postoperative seizures. CONCLUSIONS: The EEG in infants during deep hypothermic circulatory arrest displayed predictable changes. We identified an electroencephalographic pattern following the isoelectric period that may predict seizure development in the subsequent 48 hours.