Dosage Related Efficacy and Tolerability of Cannabidiol in Children With Treatment-Resistant Epileptic Encephalopathy: Preliminary Results of the CARE-E Study

Purpose: There is uncertainty regarding the appropriate dose of Cannabidiol (CBD) for childhood epilepsy. We present the preliminary data of seven participants from the Cannabidiol in Children with Refractory Epileptic Encephalopathy (CARE-E) study. Methods: The study is an open-label, prospective, dose-escalation trial. Participants received escalating doses of a Cannabis Herbal Extract (CHE) preparation of 1:20 Δ⁹-tetrahydrocannabinol (THC): CBD up to 10-12 mg CBD/kg/day. Seizure frequency was monitored in daily logs, participants underwent regular electroencephalograms, and parents filled out modified Quality of Life in Childhood Epilepsy (QOLCE) and Side Effect rating scale questionnaires. Steady-state trough levels (C_{ss, Min}) of selected cannabinoids were quantified. Results: All seven participants tolerated the CHE up to 10-12 mg CBD/kg/day and had improvements in seizure frequency and QOLCE scores. C_{SS, Min} plasma levels for CBD, THC, and cannabichromene (CBC) showed dose-independent pharmacokinetics in all but one participant. C_{SS, Min} CBD levels associated with a >50% reduction in seizures and seizure freedom were lower than those reported previously with purified CBD. In most patients, C_{SS, Min} levels of THC remained lower than what would be expected to cause intoxication. Conclusion: The preliminary data suggest an initial CBD target dose of 5-6 mg/kg/day when a 1:20 THC:CBD CHE is used. Possible non-linear pharmacokinetics of CBD and CBC needs investigation. The reduction in seizure frequency seen suggests improved seizure control when a whole plant CHE is used. Plasma THC levels suggest a low risk of THC intoxication when a 1:20 THC:CBD CHE is used in doses up to 12 mg/kg CBD/kg/day.

Cannabis for the treatment of paediatric epilepsy? An update for Canadian paediatricians

The plant Cannabis sativa produces over 140 known cannabinoids. These chemicals generate considerable interest in the medical research community for their possible application to several intractable disease conditions. Recent reports have prompted parents to strongly consider Cannabis products to treat their children with drug resistant epilepsy. Physicians, though, are reluctant to prescribe Cannabis products due to confusion about their regulatory status and limited clinical data supporting their use. We provide the general paediatrician with a brief review of cannabinoid biology, the literature regarding their use in children with drug resistant epilepsy, the current Health Canada and Canadian Paediatric Society recommendations and also the regulations from the physician regulatory bodies for each province and territory. Given the complexities of conducting research on Cannabis products for children with epilepsy, we also discuss outstanding research objectives that must be addressed to support Cannabis products as an accepted treatment option for children with refractory epilepsy.

The protocol for the Cannabidiol in children with refractory epileptic encephalopathy (CARE-E) study: a phase 1 dosage escalation study

BACKGROUND

Initial studies suggest pharmaceutical grade cannabidiol (CBD) can reduce the frequency of convulsive seizures and lead to improvements in quality of life in children affected by epileptic encephalopathies. With limited access to pharmaceutical CBD, Cannabis extracts in oil are becoming increasingly available. Physicians show reluctance to recommend Cannabis extracts given the lack of high quality safety data especially regarding the potential for harm caused by other cannabinoids, such as Δ9-tetrahydrocannabinol (Δ9-THC). The primary aims of the study presented in this protocol are (i) To determine whether CBD enriched Cannabis extract is safe and well-tolerated for pediatric patients with refractory epilepsy, (ii) To monitor the effects of CBD-enriched Cannabis extract on the frequency and duration of seizure types and on quality of life.

METHODS

Twenty-eight children with treatment resistant epileptic encephalopathy ranging in age from 1 to 10 years will be recruited in four Canadian cities into an open-label, dose-escalation phase 1 trial. The primary objectives for the study are (i) To determine if the CBD-enriched Cannabis herbal extract is safe and well-tolerated for pediatric patients with treatment resistant epileptic encephalopathy and (ii) To determine the effect of CBD-enriched Cannabis herbal extract on the frequency and duration of seizures. Secondary objectives include (i) To determine if CBD-enriched Cannabis herbal extracts alter steady-state levels of co-administered anticonvulsant medications. (ii) To assess the relation between dose escalation and quality of life measures, (iii) To determine the relation between dose escalation and steady state trough levels of bioactive cannabinoids. (iv) To determine the relation between dose escalation and incidence of adverse effects.

DISCUSSION

This paper describes the study design of a phase 1 trial of CBD-enriched Cannabis herbal extract in children with treatment-resistant epileptic encephalopathy. This study will provide the first high quality analysis of safety of CBD-enriched Cannabis herbal extract in pediatric patients in relation to dosage and pharmacokinetics of the active cannabinoids.

TRIAL REGISTRATION

http://clinicaltrials.gov [Internet]. Bethesda (MD): National Library of Medicine (US). 2016 Dec 16. Identifier NCT03024827, Cannabidiol in Children with Refractory Epileptic Encephalopathy: CARE-E; 2017 Jan 19 [cited 2017 Oct]; Available from: http://clinicaltrials.gov/ct2/show/NCT03024827.

Quantitative phenotypic and network analysis of 1q44 microdeletion for microcephaly

As genome wide techniques become more common, an increasing proportion of patients with intellectual disability (ID) are found to have genetic defects allowing genotype-phenotype correlations. Previously, AKT3 deletion was suggested to be responsible for microcephaly in patients with 1q43-q44 deletion syndrome, but this does not correspond to all cases. We report a case of a de novo 1q44 deletion in an 8-year-old boy with microcephaly in whom AKT3 is not deleted. We used a systematic review of the literature, our patient, and network analysis to gain a better understanding of the genetic basis of microcephaly in 1q deletion patients. Our analysis showed that while AKT3 deletion is associated with more severe (≤3 SD) microcephaly in 1q43-q44 deletion patients, other genes may contribute to microcephaly in AKT3 intact patients with microcephaly and 1q43-44 deletion syndrome. We identified a potential role for HNRNPU, SMYD3, NLRP3, and KIF26B in microcephaly. Overall, our study highlights the need for network analysis and quantitative measures reporting in the phenotypic analysis of a complex genetic syndrome related to copy number variation.

Inflammasome induction in Rasmussen's encephalitis: cortical and associated white matter pathogenesis

Background

Rasmussen’s encephalitis (RE) is an inflammatory encephalopathy of unknown cause defined by seizures with progressive neurological disabilities. Herein, the pathogenesis of RE was investigated focusing on inflammasome activation in the brain.

Methods

Patients with RE at the University of Alberta, Edmonton, AB, Canada, were identified and analyzed by neuroimaging, neuropsychological, molecular, and pathological tools. Primary human microglia, astrocytes, and neurons were examined using RT-PCR, enzyme-linked immunosorbent assay (ELISA), and western blotting.

Results

Four patients with RE were identified at the University of Alberta. Magnetic resonance imaging (MRI) disclosed increased signal intensities in cerebral white matter adjacent to cortical lesions of RE patients, accompanied by a decline in neurocognitive processing speed (P <0.05). CD3ϵ, HLA-DRA, and TNFα together with several inflammasome-associated genes (IL-1β, IL-18, NLRP1, NLRP3, and CASP1) showed increased transcript levels in RE brains compared to non-RE controls (n = 6; P <0.05). Cultured human microglia displayed expression of inflammasome-associated genes and responded to inflammasome activators by releasing IL-1β, which was inhibited by the caspase inhibitor, zVAD-fmk. Major histocompatibility complex (MHC) class II, IL-1β, caspase-1, and alanine/serine/cysteine (ASC) immunoreactivity were increased in RE brain tissues, especially in white matter myeloid cells, in conjunction with mononuclear cell infiltration and gliosis. Neuroinflammation in RE brains was present in both white matter and adjacent cortex with associated induction of inflammasome components, which was correlated with neuroimaging and neuropsychological deficits.

Conclusion

Inflammasome activation likely contributes to the disease process underlying RE and offers a mechanistic target for future therapeutic interventions.

A clinical and etiologic profile of spastic diplegia

To identify the clinical and etiologic profile of children with spastic diplegia, the medical records of patients with spastic diplegia in a single practice over a 12-year period were systematically and retrospectively reviewed. Clinical factors and possible etiology based on investigations were identified. Univariate and binomial logistical regression analyses were undertaken to identify factors correlating with an etiologic determination. Chart review identified 54 children with spastic diplegia. There were 31 (57.4%) preterm children and 23 (42.6%) term children. Periventricular leukomalacia was diagnosed in 24 (44.4%) children (26.1% of term children, 58.1% of preterm children). An etiology was not identified in 25 (46.3%) children: 14 (60.9%) term children and 11 (35.5%) preterm children. Periventricular leukomalacia among all children correlated with a birth weight less than 2000 gm (P = 0.037), history of neonatal resuscitation (P = 0.004), and gestation less than 33 weeks (P = 0.001). Factors specifically associated with periventricular leukomalacia in term children were a problematic perinatal history (P = 0.011), a history of neonatal resuscitation (P = 0.011), and a history of neonatal respiratory distress (P = 0.046). Regression analysis revealed a correlation between an abnormal perinatal history and an etiology of periventricular leukomalacia among term children (odds ratio 8.67, 95% confidence interval 2.51-29.97, P = 0.001). Approximately half of all children with spastic diplegia encountered in clinical practice will have an etiology identified.

Outcomes in pediatric epilepsy: seeing through the fog

To identify clinical and predictive features of outcome in cryptogenic epilepsy in pediatric neurology practice, the medical records of all patients with cryptogenic epilepsy (as defined by the International League Against Epilepsy) in a single pediatric neurology practice over a 12-year interval with at least 2 years of follow-up were systematically and retrospectively reviewed. Review revealed 60 children with cryptogenic epilepsy: 32 (53.3%) males, 11 (18.3%) prior febrile seizure, 9 (15.0%) developmental delay at onset, and 38 (63.3%) placement in regular classes. Twenty-two (35.7%) had generalized seizures. Mean follow-up after initiating antiepileptic medication was 53 months (range 24-128 months). Four (6.7%) were intractable; 4 (6.7%) had very poor outcomes; 8 (13.3%) had poor outcomes; 44 (73.3%) were well controlled. Sixteen (26.7%) and 31 (51.7%) had seizure recurrence within the last 12 and 24 months, respectively. Twenty-nine (48.3%) were seizure-free for at least 24 months. Factors associated with a poor outcome include seizure recurrence in the 6- to 12-month interval after therapy initiation (P = 0.006) and developmental delay at onset (P = 0.023). This case series suggests that children with cryptogenic epilepsy tend to have a favorable outcome. Seizure recurrence in the first months after therapy initiation and developmental delay apparent at onset are predictive of poor outcome.

The human steroidogenic acute regulatory (StAR) gene is expressed in the urogenital system and encodes a mitochondrial polypeptide

The first enzymatic step in the biosynthesis of steroid hormones occurs in the mitochondrial inner membrane and is dependent on the mobilization of cholesterol from cellular stores. We report on the isolation of a human cDNA which encodes a mitochondrial protein called steroidogenic acute regulatory (StAR) protein, implicated in transport of cholesterol into mitochondria. Nucleotide and predicted amino acid sequence analyses indicate that the human and murine polypeptides are highly conserved, sharing 87% identity with an overall homology of 92%. Analysis of the distribution of StAR mRNA transcripts in human tissues by Northern blotting reveals several mRNA species, the most abundant of which is a 1.8 kb mRNA transcript present in testes, ovaries and kidneys. Using in vitro translated protein, we demonstrate that the StAR gene product can be efficiently imported into exogenously added mitochondria.

Hereditary sensory neuropathy: a case with pain and temperature dissociation

A case of hereditary sensory neuropathy is described resembling Dyck's Type I hereditary sensory neuropathy. Sensory testing revealed marked pain impairment in feet and hands shading at mid calf to normal at mid thigh and shading above the wrist to normal at the elbow. Other sensory modalities including temperature were intact except painful heat and painful cold and they produced very little if any discomfort. Stimuli at 0 degrees C or 45 degrees to 70 degrees C elicited a temperature response but not pain. Sural nerve biopsy findings (including electromicroscopy) were consistent with a diagnosis of Type I hereditary sensory neuropathy, but also showed evidence of abortive axonal regeneration and profound Schwann cell vacuolation.