Grant: Project Grant - Priority Announcement: Integrated Cannabis Research Strategy

Close to 30% of adults with intellectual and developmental disabilities (IDD) have behavioural problems of aggression. These behavioural problems lead to reduced quality of life and burden to this population and their families. Unfortunately, current medical treatments for managing aggression are associated with a high risk of side effects in people with IDD and are inadequately studied. Anecdotal reports suggest that medical cannabinoids are a potentially viable option for reducing aggression in adults with IDD. But empirical data on tolerability, safety, and efficacy is scarce. Our preliminary findings from our ongoing pilot open-label trial suggest that nabilone, a 9-tetrahydrocannabinol (THC) analogue and a medical cannabinoid, may be quite effective in reducing aggressive behavioural problems in adults with IDD. We plan to study adults with IDD who have aggressive behaviours to test nabilone's ability to improve behavioural problems. Participants will be randomly assigned to take either nabilone or a placebo ("dummy") over 6 weeks. Neither patients nor study personnel know if a placebo or nabilone is being given. All participants will have their aggressive behaviours and adverse events measured at each visit and will receive assessments of direct observation of behaviours, global clinical state, quality of life, anxiety, cognitive performance, and their caregivers' distress levels at both the start and the end of the study. After the trial is over, all participants will be given a choice to continue taking nabilone for an additional 6 weeks. We believe that the patients taking nabilone will have a greater reduction in aggressive behaviours than those who are given the placebo, leading to improvements in anxiety, quality of life, and caregiver's distress level.