Epilepsy is a chronic disease characterized by recurrent unprovoked seizures. Up to 30% of children with epilepsy will be refractory to standard anticonvulsant therapy, and those with epileptic encephalopathy can be particularly challenging to treat. The endocannabinoid system can modulate the physiologic processes underlying epileptogenesis. The anticonvulsant properties of several cannabinoids, namely Δ-tetrahydrocannabinol and cannabidiol (CBD), have been demonstrated in both in vitro and in vivo studies. Cannabis-based therapies have been used for millennia to treat a variety of diseases including epilepsy. Several studies have shown that CBD, both in isolation as a pharmaceutical-grade preparation or as part of a CBD-enriched cannabis herbal extract, is beneficial in decreasing seizure frequency in children with treatment-resistant epilepsy. Overall, cannabis herbal extracts appear to provide greater efficacy in decreasing seizure frequency, but the studies assessing cannabis herbal extract are either retrospective or small-scale observational studies. The two large randomized controlled studies assessing the efficacy of pharmaceutical-grade CBD in children with Dravet and Lennox-Gastaut syndromes showed similar efficacy to other anticonvulsants. Lack of data regarding appropriate dosing and pediatric pharmacokinetics continues to make authorization of cannabis-based therapies to children with treatment-resistant epilepsy challenging.
At the maximum tested dose (10–12 mg/kg per day), CHE led to an average seizure reduction across all children of 74%, with three being seizure free.
Data on the first seven children, four with Dravet syndrome and three with Lennox-Gastaut, enrolled at the University of Saskatchewan’s clinical site made up this report.
A team led by researchers at University of Saskatchewan, Canada, are conducting an open-label Phase 1 clinical study (NCT03024827) called CARE-E. Scientists are exploring the safety and impact of increasing doses of CBD-enriched cannabis herbal extract (CHE) used as add-on therapy in up 28 children (ages 1 to 10) with epileptic encephalopathy resistant to standard anticonvulsant therapy. The mixture, called CanniMed 1:20, contains 1 mg/ml of THC and 20 mg/ml of CBD.
Data also showed the treatment was generally safe and well-tolerated.
“Some of the improvements in quality of life were really dramatic with some of the children having huge improvements in their ability to communicate with their families. Some of these children started to talk or crawl for the first time. They became more interactive with their families and loved ones,” Huntsman said.
All started CHE treatment with an initial CBD dose of 2–3 mg/kg per day. Over the following three months, the dose was increased every four weeks up to a maximum of 10–12 mg/kg per day. Children were then weaned off CHE over their final month of trial participation.
Better quality of life was also reported, with greatest improvements being on the cognitive, social and emotional functioning subscales of the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-55).
When conventional treatments do not work to control seizures, as is the case for roughly 30% of people with epilepsy, it is not unreasonable to consider CBD oil. However, this should only be considered after a thorough evaluation at a specialized epilepsy center to look at whether all possible treatments (including FDA-approved new and add-on medicines, dietary therapy, devices, and surgery) have been reasonably tried.
The use of cannabis to treat epilepsy and other neurological conditions has been studied for a number of years. It has been hotly debated too.
NEJM May 2018
Should a person with epilepsy pursue medical cannabis if all other medications do not work?
*The Agriculture and Nutrition Act of 2018 (H.R. 2) legalizes hemp and hemp-derived CBD. The bill changes the definition of hemp to encompass any plant or product derived from the plant that contain less than 0.3% THC by dry weight and classifies them as exempt from the controlled substance restrictions applied to marijuana. The law further amends the Controlled Substances Act to exempt hemp from Schedule I drugs.
The FDA approval and Drug Enforcement Administration (DEA) scheduling of Epidiolex brings to market the first plant-based drug derived from the cannabis plant in the U.S.
A summary of the Epidiolex clinical trials is found below:
The Journal of Child Neurology hosted a special report podcast about cannabis on March 6, 2017. In the report, Dr. Alison Christy interviews Dr. Jackie Gofshteyn, a resident in pediatric neurology at Children’s Hospital of Philadelphia, about her article, “Cannabidiol as a Potential Treatment for Febrile Infection-Related Epilepsy Syndrome (FIRES) in the Acute and Chronic Phases.” Dr. Christy also speaks with epilepsy.com’s medical cannabis editor, Dr. Anup Patel of Nationwide Children’s Hospital, about his article, “Medical Marijuana in Pediatric Neurological Disorders.” Margo Roemeling, a third year medical student at Oregon Health and Sciences University, shares the learning topic on the history and use of marijuana in the treatment of pediatric neurologic conditions.