Cannabis Extract in Refractory Epilepsy Study

Background: Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) are the two major compounds found in the cannabis plant. Reports from patients, families, and the scientific community suggest that CBD (when used as an add-on therapy) decreases the number of convulsive seizures in children and adults with Dravet syndrome, Lennox-Gastaut syndrome, and Tuberous sclerosis complex. Trial design: Phase III, double-blind, randomized, placebo-controlled, parallel-group trial, followed by an open phase where treatment allocation will be revealed and all participants will either continue or begin receiving the active study drug. Participants: Adults (18 years of age and older) with drug-resistant epilepsy, including patients with Dravet and Lennox Gastaut syndromes, and patients with frequent convulsive seizures (e.g., tonic, tonic-clonic, atonic, drop attacks, and focal motor seizures). Interventions: Capsules containing a ratio of 16 CBD: 1 THC oil at a maximum total daily dose of approximately 300 mg of CBD per day, divided into equal doses in the morning and evening. Comparator: Placebo capsules containing high-oleic sunflower oil and no active or medicinal ingredients. Outcomes: Frequency of seizures; side effects; blood levels of AEDs, CBD, THC, and liver enzymes; impact on cognition and quality of life; genetics. Sample size: A total of 80 participants (40 assigned to treatment and 40 to control group) recruited from Toronto Western Hospital in Toronto, and University Hospital in London, Ontario. Time: Each participant will be enrolled for approximately 16 to 18 weeks, while the clinical trial is expected to take place over a period of two years.