“The Dravet syndrome is a complex childhood epilepsy disorder that is associated with drug-resistant seizures and a high mortality rate. We studied cannabidiol for the treatment of drug-resistant seizures in the Dravet syndrome. Among patients with the Dravet syndrome, cannabidiol resulted in a greater reduction in convulsive-seizure frequency than placebo and was associated with higher rates of adverse events. The importance of this study is that, unlike most other antiseizure medication trials, it assesses a treatment in a specific epilepsy syndrome with a known genetic basis. CBD resulted in a significant decrease of convulsive seizures and seizures of all types in Dravet syndrome, a pharmacoresistant epilepsy known to be associated with high mortality rates.” http://epilepsycurrents.org/doi/10.5698/1535-7597.17.5.281?code=amep-site
Category Archives: Epilepsy
Cannabinoids for epilepsy: What do we know and where do we go?
“Over the past decade there has been an increasing interest in using cannabinoids to treat a range of epilepsy syndromes following reports of some remarkable responses in individual patients.
The situation is complicated by the fact that these agents do not appear to work via their attachment to endogenous cannabinoid receptors. Their pharmacokinetics are complex, and bioavailability is variable, resulting in difficulty in developing a suitable formulation for oral delivery. Drug interactions also represent another complication in their everyday use.
Nevertheless, recent randomized, placebo-controlled trials with cannabidiol support its efficacy in Dravet and Lennox-Gastaut syndromes.
Further placebo-controlled studies are underway in adults with focal epilepsy using cannabidivarin. The many unanswered questions in the use of cannabinoids to treat epileptic seizures are briefly summarized in the conclusion.”
https://www.ncbi.nlm.nih.gov/pubmed/29214639
http://onlinelibrary.wiley.com/doi/10.1111/epi.13973/abstract
Inhibition of monoacylglycerol lipase terminates diazepam-resistant status epilepticus in mice and its effects are potentiated by a ketogenic diet.
“Status epilepticus (SE) is a life-threatening and commonly drug-refractory condition. Novel therapies are needed to rapidly terminate seizures to prevent mortality and morbidity.
Monoacylglycerol lipase (MAGL) is the key enzyme responsible for the hydrolysis of the endocannabinoid 2-arachidonoylglycerol (2-AG) and a major contributor to the brain pool of arachidonic acid (AA). Inhibiting of monoacylglycerol lipase modulates synaptic activity and neuroinflammation, 2 mediators of excessive neuronal activation underlying seizures.
We studied the effect of a potent and selective irreversible MAGL inhibitor, CPD-4645, on SE that was refractory to diazepam, its neuropathologic sequelae, and the mechanism underlying the drug’s effects.
SIGNIFICANCE:
MAGL represents a novel therapeutic target for treating status epilepticus and improving its sequelae. CPD-4645 therapeutic effects appear to be predominantly mediated by modulation of neuroinflammation.”
Cannabidiol as a treatment for epilepsy
“Despite an increasing number of anti-epileptic drugs (AEDs), the proportion of drug-resistant cases of epilepsy has remained fairly static at around 30% and the search for new and improved AEDs continues.
Cannabis has been used as a medical treatment for epilepsy for thousands of years; it contains many active compounds, the most important being tetrahydrocannabinol, which has psychoactive properties, and cannabidiol, which does not.
Animal models and clinical data to date have suggested that cannabidiol is more useful in treating epilepsy; there is limited evidence that tetrahydrocannabinol has some pro-convulsant effects in animal models. The mechanism by which cannabidiol exerts its anti-convulsant properties is currently unclear.
Conclusion. The evidence is increasing that cannabidiol is an effective treatment option for childhood onset severe treatment-resistant epilepsies with a tolerable side effect and safety profile. Further evidence is needed before cannabidiol can be considered in more common or adult onset epilepsies. Longer-term safety data for cannabidiol, particularly considering its effects on the developing brain, are also required.”
https://link.springer.com/article/10.1007%2Fs00415-017-8663-0
Single-Dose Pharmacokinetics of Oral Cannabidiol Following Administration of PTL101: A New Formulation Based on Gelatin Matrix Pellets Technology.
“Cannabidiol (CBD) is the main nonpsychoactive component of the cannabis plant. It has been associated with antiseizure, antioxidant, neuroprotective, anxiolytic, anti-inflammatory, antidepressant, and antipsychotic effects.
PTL101 is an oral gelatin matrix pellets technology-based formulation containing highly purified CBD embedded in seamless gelatin matrix beadlets. Study objectives were to evaluate the safety and tolerability of PTL101 containing 10 and 100 mg CBD, following single administrations to healthy volunteers and to compare the pharmacokinetic profiles and relative bioavailability of CBD with Sativex oromucosal spray (the reference product) in a randomized, crossover study design.
Administration of PTL101 containing 10 CBD, led to a 1.7-fold higher Cmax and 1.3-fold higher AUC compared with the oromucosal spray. Tmax following both modes of delivery was 3-3.5 hours postdosing. CBD exhibited about a 1-hour lag in absorption when delivered via PTL101. A 10-fold increase in the dose resulted in an ∼15-fold increase in Cmax and AUC. Bioavailability of CBD in the 10-mg PTL101 dose was 134% relative to the reference spray.
PTL101 is a pharmaceutical-grade, user-friendly oral formulation that demonstrated safe and efficient delivery of CBD and therefore could be an attractive candidate for therapeutic indications.”
https://www.ncbi.nlm.nih.gov/pubmed/29125702
http://onlinelibrary.wiley.com/doi/10.1002/cpdd.408/abstract
Efficacy and safety of cannabis for treating children with refractory epilepsy.
“The aim of this literature review was to examine the evidence base for the safety and efficacy of cannabis in treating children with refractory epilepsy. Clinical and medical databases were searched and four articles were included in the final analysis, which included retrospective reviews and open-label trials with a total sample size of 424. One clinical trial included administration of cannabidiol, the non-psychoactive compound of cannabis, while the other three articles stated that the compound administered to participants contained tetrahydrocannabidiol, the psychoactive constituent of cannabis.
Cannabis may reduce seizures in some children and young people with refractory epilepsy, however, its success may be affected by aetiology of the epilepsy or concomitant anti-epileptic drug use, and a therapeutic dose has not been found. Positive side effects were also found including improved sleep, alertness and mood. More research is needed on this subject, including randomised controlled trials. Nurses who are aware of patients and families wishing to trial cannabis for refractory epilepsy should have full and frank discussions.”
Cannabinoid receptor 1/2 double-knockout mice develop epilepsy.
“The endocannabinoid system has gained attention as an important modulator of activity in the central nervous system. Initial studies focused on cannabinoid receptor 1 (CB1), which is widely expressed in the brain, but recent work also implicates cannabinoidreceptor 2 (CB2) in modulating neuronal activity.
Both receptors are capable of reducing neuronal activity, generating interest in cannabinoid receptor agonists as potential anticonvulsants.
CB1 (Cnr1) and CB2 (Cnr2) single-knockout mice have been generated, with the former showing heightened seizure sensitivity, but not overt seizures. Given overlapping and complementary functions of CB1 and CB2 receptors, we queried whether double-knockout mice would show an exacerbated neurological phenotype.
Strikingly, 30% of double-knockout mice exhibited provoked behavioral seizures, and 80% were found to be epileptic following 24/7 video-electroencephalographic monitoring. Single-knockout animals did not exhibit seizures. These findings highlight the importance of the endocannabinoid system for maintaining network stability.”
https://www.ncbi.nlm.nih.gov/pubmed/29105060
http://onlinelibrary.wiley.com/doi/10.1111/epi.13930/abstract
The use of cannabidiol for seizure management in patients with brain tumor-related epilepsy.
“Epilepsy, commonly encountered by patients with brain tumors, is often refractory to standard therapies. Our aim was to examine the safety and efficacy of pharmaceutical grade cannabidiol (CBD; Epidiolex, GW Pharmaceuticals) in those patients with epilepsy with concomitant tumors enrolled in The University of Alabama at Birmingham CBD Program (NCT02700412 and NCT02695537). Of the three patients with refractory seizures and a history of a primary brain tumor, two had improvement in seizure frequency and all three had improvement in seizure severity. These pilot results suggest that CBD should be further studied for the treatment of brain tumor-related epilepsy.”
https://www.ncbi.nlm.nih.gov/pubmed/29063814
http://www.tandfonline.com/doi/abs/10.1080/13554794.2017.1391294?journalCode=nncs20
Medical Cannabinoids in Children and Adolescents: A Systematic Review
“CONTEXT: Legalization of medical marijuana in many states has led to a widening gap between the accessibility and the evidence for cannabinoids as a medical treatment.
OBJECTIVE: To systematically review published reports to identify the evidence base of cannabinoids as a medical treatment in children and adolescents.
RESULTS: Evidence for benefit was strongest for chemotherapy-induced nausea and vomiting, with increasing evidence of benefit for epilepsy.” http://pediatrics.aappublications.org/content/early/2017/10/19/peds.2017-1818
“Limited data on medical cannabis use in children. Strongest evidence supports use to reduce seizures, side effects of chemotherapy.” https://www.sciencedaily.com/releases/2017/10/171023094606.htm
“Marijuana Can Help Children with Seizures, Cancer Nausea” https://www.healthline.com/health-news/marijuana-can-help-children-with-seizures-cancer-nausea
“Medical Marijuana Reduces CINV, Seizures in Children” https://www.medscape.com/viewarticle/887616
The Role of BK Channels in Antiseizure Action of the CB1 Receptor Agonist ACEA in Maximal Electroshock and Pentylenetetrazole Models of Seizure in Mice.
“The anticonvulsant effect of cannabinoid compound has been shown in various models of seizure. On the other hand, there are controversial findings about the role of large conductance calcium-activated potassium (BK) channels in the pathogenesis of epilepsy. Also, there is no data regarding the effect of co-administration of cannabinoid type 1 (CB1) receptor agonists and BK channels antagonists in the acute models of seizure in mice.
In this study, the effect of arachidonyl-2′-chloroethylamide (ACEA), a CB1 receptor agonist, and a BK channel antagonist, paxilline, either alone or in combination was investigated.
Both pentylenetetrazole (PTZ) and maximal electroshock (MES) acute models of seizure were used to evaluate the protective effects of drugs. Mice were randomly selected in different groups: (i) control group; (ii) groups that received different doses of either paxilline or ACEA; and (iii) groups that received combinations of ACEA and paxillin at different doses. In MES model, prevention of hindlimb tonic extension (HLTE) was considered as protective effect. In PTZ model, the required dose of PTZ (mg/kg) to induce tonic-clonic seizure with loss of righting reflex was considered as seizure threshold. In PTZ model, while administration of ACEA per se (5 and 10 mg/kg) caused protective effect against seizure; however, co-administration of ACEA and ineffective doses of paxilline attenuated the antiseizure effects of paxilline. In MES model, while pretreatment by ACEA showed protective effects against seizure; however, co-administration of paxilline and ACEA caused an antagonistic interaction for their antiseizure properties.
Our results showed a protective effect of ACEA in both PTZ and MES acute models of seizure. This effect was attenuated by co-administration with paxilline, suggesting the involvement of BK channels in antiseizure activity of ACEA.”