Study Shows that Cannabidiol (Epidiolex®) has Antiseizure Activity Independent of Its Interactions with Clobazam (Onfi®)

Abstract, published in Epilepsia

Four pivotal randomized placebo-controlled trials have demonstrated that “add-on” therapy with cannabidiol (CBD) improves seizure control in patients with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS). Between 47% and 68% of patients given CBD treatment in these trials were receiving clobazam (CLB), which shows complex interactions with CBD resulting in an increased in concentration of the active metabolite norclobazam. This raises concern as to the role played by these interactions when evaluating the reduction in seizure frequency in CBD-treated patients, and the question of whether CBD alone has clinically significant antiseizure effects.

This study appraised available evidence on the clinical consequences of the CBD-CLB interaction, focusing on subgroup analyses of seizure outcomes in patients on and off CLB comedication in the pivotal CBD trials. Evaluation of the results of individual trials clearly showed that improvement in seizure control over placebo was greater when CBD was added on to CLB than when it was added on to other medications. However, seizure control was also improved in patients off CLB, and despite the small sample size, the difference vs placebo was statistically significant in one of the two LGS trials.

Stronger evidence for an antiseizure effect of CBD independent of an interaction with CLB comes from analyses of seizure outcomes in the pooled population of LGS and DS patients not receiving CLB comedication. Although these results need to account for methodological limitations, they provide the best clinical evidence to date that CBD exerts therapeutic effects in patients with epilepsy that are independent of its interaction with CLB. Greater antiseizure effects and a greater burden of adverse effects, are observed when CBD is combined with CLB.

Neurologists’ Perspectives on Medical Cannabis for Pediatric Drug-Eesistant Epilepsy in Canada

Purpose: To understand the experiences with and perspectives of neurologists about the use of medical cannabis in the treatment of pediatric drug-resistant epilepsy.

Results: The 12 interviewed neurologists generally perceived medical cannabis as a viable treatment option for children with drug-resistant epilepsy; however, participants identified important gaps in the evidence and implications for their practices. Six themes were generated from the content of the interviews: learning about medical cannabis; perceptions about medical cannabis; discussing medical cannabis with parents; experiences with medical cannabis authorization; barriers to authorizing medical cannabis; and the impact of medical cannabis on clinical care. Of note, while some neurologists took on all aspects of the children’s care, including medical cannabis, others referred interested families to non-neurology health care professionals.

Conclusions: Researchers state that these findings highlight the diverse opinions and experiences of neurologists in Canada with medical cannabis for the treatment of drug-resistant epilepsy in children, including with the authorization process and caring for children using medical cannabis. Additional education about medical cannabis may be warranted, to better prepare neurologists to have informed and open conversations with parents about this treatment option and to provide care for children using medical cannabis.

A dropper adding liquid to an extract in a bottle with cannibals leafs in the background.

XPhyto Therapeutics Epilepsy Treatment Program

XPhyto is pleased to announce significant progress with respect to development of its cannabidiol (CBD) based epilepsy product. Further to the company’s press release, titled “Epilepsy Treatment to be Developed with XPhyto Therapeutics Thin Film Delivery System,” and based on recent positive product development results, XPhyto will be advancing the program to clinical studies immediately.

In the past three months, Vektor Pharma TF GmbH (“Vektor”), the Company’s wholly owned German subsidiary, has completed the initial stage of product development and established a number of critical parameters necessary for an efficient and well-defined dissolvable oral CBD dosage form. The Company is now finalizing the formulation and preparing for European-based clinical studies in Q2 and Q3 of 2020.

XPhyto’s thin film drug delivery system was developed by Vektor, a narcotics manufacturer, importer, and researcher located in the Upper Swabia region of the German state of Baden-Württemberg. Vektor’s previous development work has included narcotics delivery systems for conventional oncology and non-oncology pain treatment, such as Fentanyl, Hydromorphone, and Oxycodone, and more recently, the development of efficient cannabis delivery and dosage systems.

The Company’s CBD-based Epilepsy treatment program is one of several dissolvable oral drug delivery initiatives for 2020. Oral thin film drug delivery is a large and growing international industry which provides an alternative to conventional solid and liquid oral dosage forms. Transparency Market Research estimates that the global market for thin film drug manufacturing will be worth US$15.984 billion by 2024 and rising at a solid 9.0% CAGR between 2019 and 2024. XPhyto’s additional oral thin film drug delivery programs include both cannabinoid and non-cannabinoid products for pain, neurology and infectious disease.

Further to the Company’s press release on March 3, 2020, XPhyto is planning to announce, in due course, an update on its infectious disease programs, particularly as they relate to products relevant to the COVID-19 pandemic.

A dropper adding liquid to an extract in a bottle with cannibals leafs in the background.

Epilepsy and Cannabidiol: A Guide to Treatment

The growing interest in cannabidiol (CBD), specifically a pure form of CBD, as a treatment for epilepsy, among other conditions, is reflected in recent changes in legislation in some countries. Although there has been much speculation about the therapeutic value of cannabis-based products as an anti-seizure treatment for some time, it is only within the last two years that Class I evidence has been available for a pure form of CBD, based on placebo-controlled RCTs for patients with Lennox-Gastaut syndrome and Dravet syndrome.

However, just as we are beginning to understand the significance of CBD as a treatment for epilepsy, in recent years, a broad spectrum of products advertised to contain CBD has emerged on the market. The effects of these products are fundamentally dependent on the purity, preparation, and concentration of CBD and other components, and consensus and standardisation are severely lacking regarding their preparation, composition, usage and effectiveness.

This review aims to provide information to neurologists and epileptologists on the therapeutic value of CBD products, principally a purified form, in routine practice for patients with intractable epilepsy.

A dropper adding liquid to an extract in a bottle with cannibals leafs in the background.

The Other Side of the Leaf: Seizures Associated with Synthetic Cannabinoid Use

There has recently been a marked rise in the medicinal use of cannabis for epilepsy and multiple other conditions. While seizures have been reported in association with synthetic cannabinoids, the clinical features and prognosis have not been studied.

Thirty patients with a history of seizures occurring within 24 h of synthetic cannabinoid use were identified from a first seizure clinic database in Perth, Western Australia between 2011 and 2016. Eight had a prior history of seizures, three related to synthetic cannabinoid use, with an additional three patients having risk factors for seizures. The presenting event was a tonic-clonic seizure in 27 patients (90%). “Kronic” was the synthetic cannabinoid used by 16 patients. Absorption was via smoking in all cases, with seizures occurring within 30 min of inhalation in 14 patients (46%).

Electroencephalography (EEG) showed epileptiform abnormalities in 11%, and neuroimaging revealed epileptogenic lesions in 12%. Nine of 24 patients with follow-up had subsequent seizures, occurring in the setting of further synthetic cannabinoid use in two patients. This seizure recurrence rate is similar to seizures provoked by other acute systemic insults. In conclusion, smoking of some synthetic cannabinoids is associated with seizures, and this may relate to an intrinsic proconvulsant effect.

Study Finds Cannabidiol (Epidiolex®) Effective in Subjects with Refractory Epilepsy with or without Simultaneous Use of Clobazam

OBJECTIVE: To evaluate the efficacy of open-label, highly purified cannabidiol (CBD, Epidiolex®) in treating refractory epilepsy relative to the concomitant use of clobazam (CLB) as well as the clinical implications of changes in CLB and norclobazam (nCLB) levels.

METHODS: Data were examined retrospectively, in patients who either used CBD with concomitant CLB or without concomitant CLB after two months of treatment with CBD and at the point of best seizure control within the first year of treatment with CBD. Responder rates (percentage of subjects with a 50 % or greater reduction in weekly seizures from their baseline) and mean reduction in weekly seizure frequency were calculated and compared between those who concomitantly used CLB and those who did not. The relationship between the change in CLB and nCLB levels and change in mean weekly seizure frequency was also investigated within the group of subjects using concomitant CLB and CBD.

RESULTS: Researchers analyzed data from 47 subjects between the ages of 2.5-51 years. There was no significant difference between the concomitant CLB (n = 32) and no concomitant CLB (n = 15) groups in terms of demographics (age (p = 0.4344), race (p = 1.0000), sex (p = 0.7507)) or most epilepsy characteristics (underlying condition (all p > 0.05), mean baseline seizure frequency (p = 0.6483)). There was only one significant difference between groups regarding seizure types (more subjects with epileptic spasms in concomitant CLB group (p = 0.0413)). Concomitant AED usage was not significantly different in the two groups (all p > 0.05). Mean reduction in weekly seizure frequency was greater at the best point of seizure control within the first year than at two months of treatment with CBD, regardless of concomitant CLB usage (all p > 0.05). There was no significant difference in reduction of mean weekly seizure frequency between those who took concomitant CLB and those who did not at either time point (all p > 0.05). There was a significantly greater responder rate for subjects taking CBD and CLB than those taking CBD without CLB only at the point of best seizure control within the first year of CBD treatment (p = 0.0240). There was no strong, significant correlation between change in nCLB or CLB levels and change in seizure frequency at either time point (all p < 0.22).

SIGNIFICANCE: With or without concomitant clobazam, cannabidiol can be effective in reducing seizure frequency. Changes in norclobazam and clobazam levels do not have a clinically significant correlation with changes in weekly seizure frequency for those taking cannabidiol with clobazam.

A dropper adding liquid to an extract in a bottle with cannibals leafs in the background.

Study Provides Insights on the Effects of Cannabidiol on Severe Form of Epilepsy, LGS

Results from a study published in the British Journal of Clinical Pharmacology may help explain why cannabidiol (CBD)—a chemical component of marijuana with no psychoactive properties—reduces the frequency of seizures in patients with a severe form of epilepsy. The effect may be explained by a drug-drug interaction between cannabidiol and the anti-seizure medication clobazam.

The form of epilepsy examined in the study is called Lennox–Gastaut syndrome. Investigators conducted clinical trial simulations for the effect of 20 mg/kg/day cannabidiol on seizure frequency in patients with this syndrome.

“The effects of cannabidiol on seizure frequency in Lennox-Gastaut patients could be explained entirely through estimated elevations of blood levels of clobazam, which might mean that cannabidiol in itself may not have any, or at best limited, antiepileptic effects,” said senior author Geert Jan Groeneveld, MD, PhD, of the Centre for Human Drug Research, in The Netherlands.

Cannabis-based Zygel Helps Reduce Seizures in Childhood Epilepsy Syndromes, Trial Reports

A cannabis-based gel formulation developed by Zynerba Pharmaceuticals can significantly reduce seizures by up to six months in children and adolescents with developmental and epileptic encephalopathies, according to Phase 2 trial data.

Developmental and epileptic encephalopathies, or DEE, is an umbrella term that includes a heterogeneous group of rare pediatric epilepsy syndromes, such as Dravet and Lennox-Gastaut syndrome, among others.

The open-label BELIEVE 1 clinical trial was designed to explore the long-term safety and efficacy of Zygel in children and adolescents with DEE. To date, the study has enrolled, by invitation, 48 participants between 3 and 16 years old, who had confirmed DEE as classified by the International League Against Epilepsy.

The participants were initially dosed daily with 250 or 500 mg of Zygel, based on their weight, but the dosage could be increased up to a maximum of 1,000 mg daily. The treatment was directly applied to the skin (transdermal delivery) on the shoulders and upper arms.

Zygel was generally well-tolerated, and the safety profile was consistent with data from previous clinical studies.

A dropper adding liquid to an extract in a bottle with cannibals leafs in the background.

Prospective Evaluation of Oral Cannabis Extracts in Children with Epilepsy Shows

PURPOSE: Interest in the use of artisanal cannabinoids in pediatric epilepsy has increased but safety and utility data are lacking. The aim of this study was to prospectively characterize the use of oral cannabis extracts (OCE) in a refractory pediatric epilepsy population.

METHODS: Families considering the use of an OCE were enrolled in a prospective observational study. Baseline seizure frequency was assessed over a period of 4 weeks. Seizure frequency, CBD and THC-COOH levels were assessed every 4 weeks during a 12-week treatment period. Response was defined as at least a 50% reduction in seizure frequency over the final 8 weeks of the study relative to baseline.

RESULTS: Consent was obtained in 32 children; 11 were excluded from analysis (3 failed to complete baseline data, 3 started OCE before completing baseline period and 5 did not start OCE) leaving 21 to be included in subsequent analyses. Median age was 10.3 years (IQR 6.8-12.6), 13 (62%) were male and median seizure frequency was 2.7 seizures/day during the baseline period. The median of the high dose of CBD that was administered during the observation period was of 0.9 (0.6-2.2) mg/kg/day. Of the 21 subjects who were included in the analysis, 5 (24%) were responders. OCE was stopped early in 3 subjects (14%) due to a perceived increase in seizures. THC-COOH and CBD blood levels did not have a significant association with response status (p = 0.95 CBD, p = 0.53 THC-COOH, N = 14).

CONCLUSION: The observed response rate [at least a 50% reduction in seizure frequency over the final 8 weeks of the study relative to baseline] in this study is similar to placebo rates in prospective randomized trials of pharmaceutical grade products and the withdrawal rate is greater than rates obtained with retrospective methods. Doses of oral cannabis extracts administered were lower than doses used in randomized trials.

Oral Cannabidiol Epidyolex Approved in Europe as Add-on Treatment for Dravet, Lennox-Gastaut Syndromes

The European Commission has approved Epidyolex (cannabidiol) as an add-on therapy to clobazam (brand names Onfi and Sympazan) for the treatment of seizures associated with Dravet syndrome and Lennox?Gastaut syndrome (LGS) in patients 2 and older.

This decision, which follows the favorable opinion of the Committee for Medicinal Products for Human Use — an arm of the European Medicines Agency (EMA) — is valid in all 28 E.U. member countries, along with Norway, Iceland, and Liechtenstein. The U.S. Food and Drug Administration had reached a similar decision to approve the treatment, under the brand name Epidiolex, in June 2018.

GW Pharmaceuticals’ Epidyolex is a purified and oral form of cannabidiol (CBD), the most common non-psychoactive cannabinoid compound in the cannabis plant. CBD is able to mimic natural compounds by acting on brain receptors, which may cause seizures when faulty.