A Double-blind, Randomized, Placebo-controlled Crossover Pilot Trial of Medical Cannabis in Adults with Tourette Syndrome

Grant Type
Grant Year
Institution Location
Institution Organization Name
Toronto Western Hospital Canada
Investigators Name
Sandor, Paul, MD

Summary: The number of effective pharmacological options for the treatment of tics is very limited. A substantial proportion of patients are not satisfied with the currently available medications due to limited efficacy or significant side-effects. New therapeutic strategies are needed for TS patients, especially for those who have not benefitted from available treatments. Two small controlled trials of short duration have investigated the effect of oral delta-9-tetrahydrocannabinol (THC), a principal psychoactive ingredient of cannabis, in TS patients. While these trials have shown promising results, the effect sizes were not as large and consistent as patients report with inhaled cannabis (smoked or vaporized). Indeed, based on our clinical experience and a retrospective study we are currently completing, patients have much greater improvement in their symptoms using inhaled cannabis than using cannabinoid pharmaceuticals. However, there have been no controlled trials of inhaled medical cannabis for TS to date. Furthermore, various medical cannabis products are authorized in Canada with different content of THC and cannabidiol (CBD), another primary cannabinoid. No data exist regarding the dosing, efficacy and safety of these products in the treatment of TS. We are thus planning to carry out a double-blind, randomized, crossover pilot clinical trial comparing three vaporized medical cannabis products with different THC and CBD content and placebo in adults with TS. The goals of this study are to: 1.Compare the efficacy of single doses of three vaporized medical cannabis products and placebo in reducing tics in adults with TS. 2.Compare the tolerability of three vaporized medical cannabis products in adults with TS. 3.Characterize the PK/PD profile of THC, 11-OH-THC (the psychoactive metabolite of THC) and CBD of three vaporized medical cannabis products and the correlation of PK/PD profile with tic symptoms. Lay Summary: For many individuals with Tourette syndrome (TS), available medications do not help with their symptoms, or cause significant side effects. There is some evidence that inhaled cannabis can be helpful and well-tolerated in adults with TS, but this has not been well studied. Our goal is to carry out a study of vaporized cannabis for tics in adults with TS. We will compare three different types of medical cannabis in terms of how much they help tics, and how much they cause side effects. Paul Sandor, M.D.; Elia Abi-Jaoude, M.D.; Lei Chen, Ph.D. Toronto Western Hospital, Toronto, Ontario M5T 2S8, Canada Award: $75,000 Tourette Association of America Inc. – Research Grant Award 2015-2016