Report from a Survey of Parents Regarding the Use of Cannabidiol (Medicinal cannabis) in Mexican Children with Refractory Epilepsy

Cannabinoids in epilepsy: clinical efficacy and pharmacological considerations

INTRODUCTION

Advances in the development of drugs with novel mechanisms of action have not been sufficient to significantly reduce the percentage of patients presenting drug-resistant epilepsy. This lack of satisfactory clinical results has led to the search for more effective treatment alternatives with new mechanisms of action.

DEVELOPMENT

The aim of this study is to examine epidemiological aspects of the use of cannabis-based products for the treatment of epilepsy, with particular emphasis on the main mechanisms of action, indications for use, clinical efficacy, and safety. We conducted a narrative review of articles gathered from the PubMed, EMBASE, and Google Scholar databases and from the reference sections of relevant publications.

CONCLUSIONS

In recent years there has been growing interest in the use of cannabis-based products for the treatment of a wide range of diseases, including epilepsy. The cannabis plant is currently known to contain more than 100 terpenophenolic compounds, known as cannabinoids. The 2 most abundant are delta-9-tetrahydrocannabinol and cannabidiol. Studies of preclinical models of epilepsy have shown that these cannabinoids have anticonvulsant properties, and 100% purified cannabidiol and cannabidiol-enriched cannabis extracts are now being used to treat epilepsy in humans. Several open-label studies and randomised controlled clinical trials have demonstrated the efficacy and safety of these products.

Use of non-medical cannabis in epilepsy: A scoping review

Objective

The use of medical cannabis among people with epilepsy (PWE) has been garnering increasing interest. In this scoping review, we aimed to summarize the literature on recreational/non-medical cannabis (NMC) use in PWE, focusing on the experience, habits, and beliefs of PWE regarding NMC.

Methods

Four databases (OVID Medline, OVID Embase, Ovid APA PsycInfo, and Web of Science) were searched for studies describing NMC use in PWE. NMC was defined as cannabis products procured from sources other than by prescription. Studies that consisted in original research and that detailed the experience, habits, and/or beliefs of PWE regarding NMC use were included in the analysis. Data pertaining to study identification, demographics, NMC use, and epilepsy characteristics were extracted. Descriptive statistical analyses and reflexive thematic analyses were performed to map these data.

Results

In total, 3,228 records were screened, and 66 were included for analysis: 45 had mainly adult samples, whereas 21 had mainly pediatric samples. Most studies were published after 2010, originated from the USA, and were cross-sectional. The median number of PWE using cannabis in these studies was 24.5 (1-37,945). No studies showcased elderly PWE, and most had predominantly Caucasian samples. The lifetime prevalence of NMC use in PWE was variable, ranging between 0.69 and 76.8%. Factors frequently associated with NMC use in PWE were male sex, younger adult age, and lower education status. Children with epilepsy took NMC primarily for seizure control, using high CBD/THC ratios, and only orally. Adults with epilepsy took NMC for various reasons including recreationally, using variable CBD/THC ratios, and predominantly through smoking. The majority of PWE across all studies perceived that NMC aided in seizure control. Other aspects pertaining to NMC use in PWE were rarely reported and often conflicting.

Conclusion

The literature on NMC use in PWE is sparse and heterogeneous, with many salient knowledge gaps. Further research is necessary to better understanding the experience, habits, and beliefs of PWE pertaining to NMC.

Children as voices and images for medicinal cannabis law reform

This article situates the movement for the legalisation of medicinal cannabis within the bigger picture of the impetus toward recreational cannabis legalisation. It describes the role played by children with epileptic syndromes in the medicinal cannabis law reform campaigns in the United Kingdom, and Queensland, New South Wales and Victoria in Australia. Noting the 'rule of rescue' and the prominence in media campaigns of children in Australian and English cases of parental disputation with clinicians about treatment for their children, it reviews whether paediatric epilepsy is a suitable test case for the legalisation of medicinal cannabis. Taking into account the vested commercial interests of Big Cannabis, the current medico-scientific knowledge of the efficacy of medicinal cannabis in controlling paediatric epileptic seizures, and issues of dignity, health privacy, and the enduring digital footprints of media coverage, the article commences discussion about the ethics of the media, parents, politicians and entrepreneurial doctors utilising parents' testimonials about the effects of medicinal cannabis as part of the cannabis law reform movement.

Mechanisms of Drug Resistance in the Pathogenesis of Epilepsy: Role of Neuroinflammation. A Literature Review

Epilepsy is a chronic neurological disorder characterized by recurring spontaneous seizures. Drug resistance appears in 30% of patients and it can lead to premature death, brain damage or a reduced quality of life. The purpose of the study was to analyze the drug resistance mechanisms, especially neuroinflammation, in the epileptogenesis. The information bases of biomedical literature Scopus, PubMed, Google Scholar and SciVerse were used. To obtain full-text documents, electronic resources of PubMed Central and Research Gate were used. The article examines the recent research of the mechanisms of drug resistance in epilepsy and discusses the hypotheses of drug resistance development (genetic, epigenetic, target hypothesis, etc.). Drug-resistant epilepsy is associated with neuroinflammatory, autoimmune and neurodegenerative processes. Neuroinflammation causes immune, pathophysiological, biochemical and psychological consequences. Focal or systemic unregulated inflammatory processes lead to the formation of aberrant neural connections and hyperexcitable neural networks. Inflammatory mediators affect the endothelium of cerebral vessels, destroy contacts between endothelial cells and induce abnormal angiogenesis (the formation of “leaky” vessels), thereby affecting the blood–brain barrier permeability. Thus, the analysis of pro-inflammatory and other components of epileptogenesis can contribute to the further development of the therapeutic treatment of drug-resistant epilepsy.

Family attitudes about and experiences with medical cannabis in children with cancer or epilepsy: an exploratory qualitative study

BACKGROUND

Cannabis is legal for recreational and medical use in Canada. Our aim was to explore family experiences using medical cannabis for children with severe conditions in the context of legalization.

METHODS

We conducted a qualitative study using semistructured interviews between April and July 2019. Participants were parents of children attending BC Children's Hospital oncology or palliative care clinics, recruited through posters, emails or referral. Participants were included if they spoke English and their child used any type of cannabis for medical purposes. Interviews included open-ended questions about the child's cannabis use. Interviews were recorded and transcribed, and thematic analysis was performed using qualitative description.

RESULTS

Ten interviews were completed with 9 mothers and 1 mother-father pair. The age range of the children was 22 months to 16 years. The primary reasons for cannabis use were epilepsy (6 children) or chemotherapy management (4 children). Five major themes were identified. 1) Child and family context, and cannabis as a last resort: children were seen as severely ill; parents sought cannabis out of desperation and responsibility to their child. 2) Varied information sources informed decision-making: parents lacked resources from health care providers and sought support from social media, industry and other families. 3) Cannabis as an ambiguous medicine: cannabis was viewed as both a serious drug that doctors should prescribe and as a natural alternative health product, safe to pursue alone. 4) Perceived effects: parents perceived medical benefits with few concerns about adverse effects. 5) Legal and financial challenges: parents were willing to obtain cannabis despite high costs and uncertain legality.

INTERPRETATION

Parents of children with severe conditions pursued medical cannabis despite obstacles and needed unbiased information to access alone. Scientific investigation is needed to develop pediatric medical guidelines to inform decisions.

Cannabis sativa subsp. sativa's pharmacological properties and health effects: A scoping review of current evidence

INTRODUCTION

Hemp (Cannabis sativa subsp. sativa), commonly used for industrial purposes, is now being consumed by the public for various health promoting effects. As popularity of hemp research and claims of beneficial effects rises, a systematic collection of current scientific evidence on hemp's health effects and pharmacological properties is needed to guide future research, clinical, and policy decision making.

OBJECTIVE

To provide an overview and identify the present landscape of hemp research topics, trends, and gaps.

METHODS

A systematic search and analysis strategy according to the preferred reporting items for systematic review and meta-analysis-ScR (PRISMA-ScR) checklist on electronic databases including MEDLINE, OVID (OVFT, APC Journal Club, EBM Reviews), Cochrane Library Central and Clinicaltrials.gov was conducted to include and analyse hemp research articles from 2009 to 2019.

RESULTS

65 primary articles (18 clinical, 47 pre-clinical) were reviewed. Several randomised controlled trials showed hempseed pills (in Traditional Chinese Medicine formulation MaZiRenWan) improving spontaneous bowel movement in functional constipation. There was also evidence suggesting benefits in cannabis dependence, epilepsy, and anxiety disorders. Pre-clinically, hemp derivatives showed potential anti-oxidative, anti-hypertensive, anti-inflammatory, anti-diabetic, anti-neuroinflammatory, anti-arthritic, anti-acne, and anti-microbial activities. Renal protective effects and estrogenic properties were also exhibited in vitro.

CONCLUSION

Current evidence on hemp-specific interventions are still preliminary, with limited high quality clinical evidence for any specific therapeutic indication. This is mainly due to the wide variation in test item formulation, as the multiple variants of this plant differ in their phytochemical and bioactive compounds. Future empirical research should focus on standardising the hemp plant for pharmaceutical use, and uniformity in experimental designs to strengthen the premise of using hemp in medicine.

Possible therapeutic applications of cannabis in the neuropsychopharmacology field

Cannabis use induces a plethora of actions on the CNS via its active chemical ingredients, the so-called phytocannabinoids. These compounds have been frequently associated with the intoxicating properties of cannabis preparations. However, not all phytocannabinoids are psychotropic, and, irrespective of whether they are psychotropic or not, they have also shown numerous therapeutic properties. These properties are mostly associated with their ability to modulate the activity of an intercellular communication system, the so-called endocannabinoid system, which is highly active in the CNS and has been found altered in many neurological disorders. Specifically, this includes the neuropsychopharmacology field, with diseases such as schizophrenia and related psychoses, anxiety-related disorders, mood disorders, addiction, sleep disorders, post-traumatic stress disorder, anorexia nervosa and other feeding-related disorders, dementia, epileptic syndromes, as well as autism, fragile X syndrome and other neurodevelopment-related disorders. Here, we gather, from a pharmacological and biochemical standpoint, the recent advances in the study of the therapeutic relevance of the endocannabinoid system in the CNS, with especial emphasis on the neuropsychopharmacology field. We also illustrate the efforts that are currently being made to investigate at the clinical level the potential therapeutic benefits derived from elevating or inhibiting endocannabinoid signaling in animal models of neuropsychiatric disorders.

Clinical Data for the Use of Cannabis-Based Treatments: A Comprehensive Review of the Literature

Objective:

To compile and synthesize the available literature describing medical cannabis use across various disease states.

Data Sources:

PubMed, EBSCO, and Google Scholar searches were conducted using MeSH and/or keywords.

Study Selection and Data Extraction:

Studies were included if they described the use of cannabis-based products and medications in the treatment of a predefined list of disease states in humans and were published in English. The extraction period had no historical limit and spanned through April 2019.

Data Synthesis:

Evidence was compiled and summarized for the following medical conditions: Alzheimer disease, amyotrophic lateral sclerosis, autism, cancer and cancer-associated adverse effects, seizure disorders, human immunodeficiency virus, inflammatory bowel disease, multiple sclerosis (MS), nausea, pain, posttraumatic stress disorder, and hospice care.

Relevance to Patient Care and Clinical Practice:

Based on identified data, the most robust evidence suggests that medical cannabis may be effective in the treatment of chemotherapy-induced nausea and vomiting, seizure disorders, MS-related spasticity, and pain (excluding diabetic neuropathy). Overall, the evidence is inconsistent and generally limited by poor quality. The large variation in cannabis-based products evaluated in studies limits the ability to make direct comparisons. Regardless of the product, a gradual dose titration was utilized in most studies. Cannabis-based therapies were typically well tolerated, with the most common adverse effects being dizziness, somnolence, dry mouth, nausea, and euphoria.

Conclusions:

As more states authorize medical cannabis use, there is an increasing need for high-quality clinical evidence describing its efficacy and safety. This review is intended to serve as a reference for clinicians, so that the risks and realistic benefits of medical cannabis are better understood.

Efficacy and safety of paediatric medicinal cannabis use: A scoping review

Introduction

The use of medicinal cannabis in the paediatric age group is increasing despite the lack of evidence for its efficacy or safety.

Objective

To map the available evidence on the efficacy and safety of medicinal cannabis in children and adolescents.

Methods

We conducted a scoping review and searched six electronic databases and grey literature. A study was eligible for inclusion when it investigated the efficacy or safety of medicinal cannabis for any condition, more than half of the participants were 0 to 18 years old, and had any study design except single case reports.

Results

We included 36 studies in our final analysis, 32 of which investigated the efficacy or safety of cannabis in treatment-resistant epilepsy. The remaining 4 studies examined patients with cancer, dysautonomia, Epidermolysis Bullosa, and motor disorders.

Conclusions

There is a lack of evidence on the efficacy and safety of medicinal cannabis in most paediatric conditions.

Cannabinoids in epilepsy: Clinical efficacy and pharmacological considerations

INTRODUCTION

Advances in the development of drugs with novel mechanisms of action have not been sufficient to significantly reduce the percentage of patients presenting drug-resistant epilepsy. This lack of satisfactory clinical results has led to the search for more effective treatment alternatives with new mechanisms of action.

DEVELOPMENT

The aim of this study is to examine epidemiological aspects of the use of cannabis-based products for the treatment of epilepsy, with particular emphasis on the main mechanisms of action, indications for use, clinical efficacy, and safety. We conducted a narrative review of articles gathered from the PubMed, EMBASE, and Google Scholar databases and from the reference sections of relevant publications.

CONCLUSIONS

In recent years there has been growing interest in the use of cannabis-based products for the treatment of a wide range of diseases, including epilepsy. The cannabis plant is currently known to contain more than 100 terpenophenolic compounds, known as cannabinoids. The 2 most abundant are delta-9-tetrahydrocannabinol and cannabidiol. Studies of preclinical models of epilepsy have shown that these cannabinoids have anticonvulsant properties, and 100% purified cannabidiol and cannabidiol-enriched cannabis extracts are now being used to treat epilepsy in humans. Several open-label studies and randomised controlled clinical trials have demonstrated the efficacy and safety of these products.

Genetic variations associated with pharmacoresistant epilepsy (Review)

Epilepsy is a common, serious neurological disorder worldwide. Although this disease can be successfully treated in most cases, not all patients respond favorably to medical treatments, which can lead to pharmacoresistant epilepsy. Drug-resistant epilepsy can be caused by a number of mechanisms that may involve environmental and genetic factors, as well as disease- and drug-related factors. In recent years, numerous studies have demonstrated that genetic variation is involved in the drug resistance of epilepsy, especially genetic variations found in drug resistance-related genes, including the voltage-dependent sodium and potassium channels genes, and the metabolizer of endogenous and xenobiotic substances genes. The present review aimed to highlight the genetic variants that are involved in the regulation of drug resistance in epilepsy; a comprehensive understanding of the role of genetic variation in drug resistance will help us develop improved strategies to regulate drug resistance efficiently and determine the pathophysiological processes that underlie this common human neurological disease.

Medical Cannabis for Intractable Epilepsy in Childhood: A Review

In recent years, cannabis has been gaining increasing interest in both the medical research and clinical fields, with regard to its therapeutic effects in various disorders. One of the major fields of interest is its role as an anticonvulsant for refractory epilepsy, especially in the pediatric population. This paper presents and discusses the current accumulated knowledge regarding artisanal cannabis and Epidiolex®, a United States Food and Drug Administration (FDA)-approved pure cannabidiol (CBD), in epilepsy management in pediatrics, by reviewing the literature and raising debate regarding further research directions.

Cannabis-based products for pediatric epilepsy: An updated systematic review

PURPOSE

To provide an up-to-date summary of the benefits and harms of cannabis-based products for epilepsy in children.

METHODS

We updated our earlier systematic review, by searching for studies published up to May 2019. We included randomized controlled trials (RCTs) and non-randomized studies (NRS) involving cannabis-based products administered to children with epilepsy. Outcomes were seizure freedom, seizure frequency, quality of life, sleep, status epilepticus, death, gastrointestinal adverse events, and emergency room visits.

RESULTS

Thirty-five studies, including four RCTs, have assessed the benefits and harms of cannabis-based products in pediatric epilepsy (12 since April 2018). All involved cannabis-based products as adjunctive treatment, and most involved cannabidiol. In the RCTs, there was no statistically significant difference between cannabidiol and placebo for seizure freedom (relative risk 6.77, 95 % confidence interval [CI] 0.36-128.38), quality of life (mean difference [MD] 0.6, 95 %CI -2.6 to 3.9), or sleep disruption (MD -0.3, 95 %CI -0.8 to 0.2). Data from both RCTs and NRS suggest that cannabidiol reduces seizure frequency and increases treatment response; however, there is an increased risk of gastrointestinal adverse events.

CONCLUSION

Newly available evidence supports earlier findings that cannabidiol probably reduces the frequency of seizures among children with drug-resistant epilepsy.

PROSPERO

CRD42018084755.

Effects of CBD-Enriched Cannabis sativa Extract on Autism Spectrum Disorder Symptoms: An Observational Study of 18 Participants Undergoing Compassionate Use

Autism Spectrum Disorders comprise conditions that may affect cognitive development, motor skills, social interaction, communication, and behavior. This set of functional deficits often results in lack of independence for the diagnosed individuals, and severe distress for patients, families, and caregivers. There is a mounting body of evidence indicating the effectiveness of pure cannabidiol (CBD) and CBD-enriched Cannabis sativa extract (CE) for the treatment of autistic symptoms in refractory epilepsy patients. There is also increasing data support for the hypothesis that non-epileptic autism shares underlying etiological mechanisms with epilepsy. Here we report an observational study with a cohort of 18 autistic patients undergoing treatment with compassionate use of standardized CBD-enriched CE (with a CBD to THC ratio of 75/1). Among the 15 patients who adhered to the treatment (10 non-epileptic and five epileptic) only one patient showed lack of improvement in autistic symptoms. Due to adverse effects, three patients discontinued CE use before 1 month. After 6-9 months of treatment, most patients, including epileptic and non-epileptic, showed some level of improvement in more than one of the eight symptom categories evaluated: Attention Deficit/Hyperactivity Disorder; Behavioral Disorders; Motor Deficits; Autonomy Deficits; Communication and Social Interaction Deficits; Cognitive Deficits; Sleep Disorders and Seizures, with very infrequent and mild adverse effects. The strongest improvements were reported for Seizures, Attention Deficit/Hyperactivity Disorder, Sleep Disorders, and Communication and Social Interaction Deficits. This was especially true for the 10 non-epileptic patients, nine of which presented improvement equal to or above 30% in at least one of the eight categories, six presented improvement of 30% or more in at least two categories and four presented improvement equal to or above 30% in at least four symptom categories. Ten out of the 15 patients were using other medicines, and nine of these were able to keep the improvements even after reducing or withdrawing other medications. The results reported here are very promising and indicate that CBD-enriched CE may ameliorate multiple ASD symptoms even in non-epileptic patients, with substantial increase in life quality for both ASD patients and caretakers.

Cannabis-based products for pediatric epilepsy: A systematic review

OBJECTIVE

To assess the benefits and harms of cannabis-based products for pediatric epilepsy.

METHODS

We identified in this living systematic review randomized controlled trials (RCTs) and nonrandomized studies (NRSs) involving children with epilepsy treated with cannabis-based products. We searched MEDLINE, Embase, PsycINFO, Cochrane Library, and gray literature (April 25, 2018). The primary outcome was seizure freedom; secondary outcomes were seizure frequency (total, ≥50% reduction), quality of life, sleep, status epilepticus, death, gastrointestinal adverse events, and visits to the emergency room. Data were pooled by random-effects meta-analysis. Risk of bias was assessed for each study, and GRADE was used to assess the quality of evidence for each outcome.

RESULTS

Four RCTs and 19 NRSs were included, primarily involving cannabidiol. All RCTs were at low risk of bias, whereas all NRSs were at high risk. Among RCTs, there was no statistically significant difference between cannabidiol and placebo in seizure freedom (relative risk [RR] = 6.77, 95% confidence interval [CI] = 0.36-128.38; 1 RCT), quality of life (mean difference = 0.6, 95% CI = -2.6 to 3.9; 3 RCTs), sleep disruption (mean difference = -0.3, 95% CI = -0.8 to 0.2; 3 RCTs), or vomiting (RR = 1.00, 95% CI = 0.51-1.96; 4 RCTs). There was a statistically significant reduction in the median frequency of monthly seizures with cannabidiol compared with placebo (-19.8%, 95% CI = -27.0% to -12.6%; 3 RCTs) and an increase in the number of participants with at least a 50% reduction in seizures (RR = 1.76, 95% CI = 1.07-2.88; 1 RCT) and diarrhea (RR = 2.25, 95% CI = 1.38-3.68; 3 RCTs). Death and status epilepticus were infrequently reported.

SIGNIFICANCE

Evidence from high-quality RCTs suggests that cannabidiol probably reduces seizures among children with drug-resistant epilepsy (moderate certainty). At this time, the evidence base is primarily limited to cannabidiol, and these findings should not be extended to all cannabis-based products.

Potential Clinical Benefits of CBD-Rich Cannabis Extracts Over Purified CBD in Treatment-Resistant Epilepsy: Observational Data Meta-analysis

This meta-analysis paper describes the analysis of observational clinical studies on the treatment of refractory epilepsy with cannabidiol (CBD)-based products. Beyond attempting to establish the safety and efficacy of such products, we also investigated if there is enough evidence to assume any difference in efficacy between CBD-rich extracts compared to purified CBD products. The systematic search took place in February/2017 and updated in December/2017 using the keywords "epilepsy" or "Dravet" or "Lennox-Gastaut" or "CDKL5" combined with "Cannabis," "cannabinoid," "cannabidiol," or "CBD" resulting in 199 papers. The qualitative assessment resulted in 11 valid references, with an average impact factor of 8.1 (ranging from 1.4 to 47.8). The categorical data of a total of 670 patients were analyzed by Fischer test. The average daily dose ranged between 1 and 50 mg/kg, with treatment length from 3 to 12 months (mean 6.2 months). Two thirds of patients reported improvement in the frequency of seizures (399/622, 64%). There were more reports of improvement from patients treated with CBD-rich extracts (318/447, 71%) than patients treated with purified CBD (81/175, 46%), [corrected] with statistical significance (p < 0.0001). Nevertheless, when the standard clinical threshold of a "50% reduction or more in the frequency of seizures" was applied, only 39% of the individuals were considered "responders," and there was no difference (p = 0.52) [corrected] between treatments with CBD-rich extracts (122/330, 37%) [corrected] and purified CBD (94/223, 42%). Patients treated with CBD-rich extracts reported lower average dose (6.0 mg/kg/day) [DOSAGE ERROR CORRECTED] than those using purified CBD (25.3 mg/kg/day). [DOSAGE ERROR CORRECTED] The reports of mild (158/216 76% vs. 148/447, 33% p < 0.001) and severe (41/155, 26% vs. 23/328, 7% p < 0.0001) [corrected] adverse effects were more frequent in products containing purified CBD than in CBD-rich extracts. CBD-rich extracts seem to present a better therapeutic profile than purified CBD, at least in this population of patients with refractory epilepsy. The roots of this difference is likely due to synergistic effects of CBD with other phytocompounds (aka Entourage effect), but this remains to be confirmed in controlled clinical studies.

Cannabidiol for Treatment of Childhood Epilepsy-A Cross-Sectional Survey

Background: The interest in cannabidiol (CBD) for treatment of epilepsy has been increasing over the last years. However, practitioner's attitudes concerning the use of CBD for epilepsy treatment appears to be divided and data about its clinical use in daily practice are not available. Objective: To improve the knowledge about the current use of CBD amongst European practitioners treating children and adolescents for epilepsy. Methods: Cross-sectional survey using an open-access online questionnaire for physicians treating children or adolescents for epilepsy within eight European countries from December 2017 to March 2018. Results: One-hundred fifty-five physicians participated in the survey. CBD is increasingly used by 45% (69/155) of participants, treating a mean (range) number of 3 (1-35) with CBD. Only 48% of the participants prescribing CBD are exclusively using purified CBD to treat children and adolescents with epilepsy, the remainder also applies preparations containing delta9-tetrahydrocannabinol (THC). Reported daily CBD doses range from < 10 to 50 mg/kg body weight. Management of CBD therapy in regard of monitoring side effects and adjusting concomitant therapy differs widely amongst participants. Their primary objective for commencing CBD is improving patient's quality of life. Participants frequently receive inquiries about CBD treatment but only 40% may actively suggest CBD as a treatment option. Of the 85 participants currently not using CBD for epilepsy treatment, 70% would consider using CBD if available in their country of practice or given the opportunity to become familiar with this treatment option. Conclusions: CBD is increasingly used by participating physicians but individual experience remains limited. There are very diverse opinions about the use of CBD to treat epilepsy in children and adolescents and widely differing views on how to manage the CBD treatment.

Evidence for cannabis and cannabinoids for epilepsy: a systematic review of controlled and observational evidence

Review evidence for cannabinoids as adjunctive treatments for treatment-resistant epilepsy. Systematic search of Medline, Embase and PsycINFO was conducted in October 2017. Outcomes were: 50%+ seizure reduction, complete seizure freedom; improved quality of life (QoL). Tolerability/safety were assessed by study withdrawals, adverse events (AEs) and serious adverse events (SAEs). Analyses were conducted in Stata V.15.0. 36 studies were identified: 6 randomised controlled trials (RCTs), 30 observational studies. Mean age of participants was 16.1 years (range 0.5-55 years). Cannabidiol (CBD) 20 mg/kg/day was more effective than placebo at reducing seizure frequency by 50%+(relative risk (RR) 1.74, 95% CI 1.24 to 2.43, 2 RCTs, 291 patients, low Grades of Recommendation, Assessment, Development and Evaluation (GRADE) rating). The number needed to treat for one person using CBD to experience 50%+ seizure reduction was 8 (95% CI 6 to 17). CBD was more effective than placebo at achieving complete seizure freedom (RR 6.17, 95% CI 1.50 to 25.32, 3 RCTs, 306 patients, low GRADE rating), and improving QoL (RR 1.73, 95% CI 1.33 to 2.26), however increased risk of AEs (RR 1.24, 95% CI 1.13 to 1.36) and SAEs (RR 2.55, 95% CI 1.48 to 4.38). Pooled across 17 observational studies, 48.5% (95% CI 39.0% to 58.1%) of patients reported 50%+ reductions in seizures; in 14 observational studies 8.5% (95% CI 3.8% to 14.5%) were seizure-free. Twelve observational studies reported improved QoL (55.8%, 95% CI 40.5 to 70.6); 50.6% (95% CI 31.7 to 69.4) AEs and 2.2% (95% CI 0 to 7.9) SAEs. Pharmaceutical-grade CBD as adjuvant treatment in paediatric-onset drug-resistant epilepsy may reduce seizure frequency. Existing RCT evidence is mostly in paediatric samples with rare and severe epilepsy syndromes; RCTs examining other syndromes and cannabinoids are needed.

PROSPERO REGISTRATION NUMBER

CRD42017055412.

Prospects of Cannabidiol for Easing Status Epilepticus-Induced Epileptogenesis and Related Comorbidities

The hippocampus is one of the most susceptible regions in the brain to be distraught with status epilepticus (SE) induced injury. SE can occur from numerous causes and is more frequent in children and the elderly population. Administration of a combination of antiepileptic drugs can abolish acute seizures in most instances of SE but cannot prevent the morbidity typically seen in survivors of SE such as cognitive and mood impairments and spontaneous recurrent seizures. This is primarily due to the inefficiency of antiepileptic drugs to modify the evolution of SE-induced initial precipitating injury into a series of epileptogenic changes followed by a state of chronic epilepsy. Chronic epilepsy is typified by spontaneous recurrent seizures, cognitive dysfunction, and depression, which are associated with persistent inflammation, significantly waned neurogenesis, and abnormal synaptic reorganization. Thus, alternative approaches that are efficient not only for curtailing SE-induced initial brain injury, neuroinflammation, aberrant neurogenesis, and abnormal synaptic reorganization but also for thwarting or restraining the progression of SE into a chronic epileptic state are needed. In this review, we confer the promise of cannabidiol, an active ingredient of Cannabis sativa, for preventing or easing SE-induced neurodegeneration, neuroinflammation, cognitive and mood impairments, and the spontaneous recurrent seizures.

Cannabinoids in the Treatment of Epilepsy: Hard Evidence at Last?

The interest in cannabis-based products for the treatment of refractory epilepsy has skyrocketed in recent years. Marijuana and other cannabis products with high content in Δ(9) - tetrahydrocannabinol (THC), utilized primarily for recreational purposes, are generally unsuitable for this indication, primarily because THC is associated with many undesired effects. Compared with THC, cannabidiol (CBD) shows a better defined anticonvulsant profile in animal models and is largely devoid of adverse psychoactive effects and abuse liability. Over the years, this has led to an increasing use of CBD-enriched extracts in seizure disorders, particularly in children. Although improvement in seizure control and other benefits on sleep and behavior have been often reported, interpretation of the data is made difficult by the uncontrolled nature of these observations. Evidence concerning the potential anti-seizure efficacy of cannabinoids reached a turning point in the last 12 months, with the completion of three high-quality placebo-controlled adjunctive-therapy trials of a purified CBD product in patients with Dravet syndrome and Lennox-Gastaut syndrome. In these studies, CBD was found to be superior to placebo in reducing the frequency of convulsive (tonic-clonic, tonic, clonic, and atonic) seizures in patients with Dravet syndrome, and the frequency of drop seizures in patients with Lennox-Gastaut syndrome. For the first time, there is now class 1 evidence that adjunctive use of CBD improves seizure control in patients with specific epilepsy syndromes. Based on currently available information, however, it is unclear whether the improved seizure control described in these trials was related to a direct action of CBD, or was mediated by drug interactions with concomitant medications, particularly a marked increased in plasma levels of N-desmethylclobazam, the active metabolite of clobazam. Clarification of the relative contribution of CBD to improved seizure outcome requires re-assessment of trial data for the subgroup of patients not comedicated with clobazam, or the conduction of further studies controlling for the confounding effect of this interaction.

The potential role of cannabinoids in epilepsy treatment

INTRODUCTION

Epilepsy is one of the world's oldest recognized and prevalent neurological diseases. It has a great negative impact on patients' quality of life (QOL) as a consequence of treatment resistant seizures in about 30% of patients together with drugs' side effects and comorbidities. Therefore, new drugs are needed and cannabinoids, above all cannabidiol, have recently gathered attention. Areas covered: This review summarizes the scientific data from human and animal studies on the major cannabinoids which have been of interest in the treatment of epilepsy, including drugs acting on the endocannabinoid system. Expert commentary: Despite the fact that cannabis has been used for many purposes over 4 millennia, the development of drugs based on cannabinoids has been very slow. Only recently, research has focused on their potential effects and CBD is the first treatment of this group with clinical evidence of efficacy in children with Dravet syndrome; moreover, other studies are currently ongoing to confirm its effectiveness in patients with epilepsy. On the other hand, it will be of interest to understand whether drugs acting on the endocannabinoid system will be able to reach the market and prove their known preclinical efficacy also in patients with epilepsy.