CANnabinoids in Pediatric ONCology

Inclusion Criteria: 1. Ages 4-17 years old at the time of enrollment 2. Diagnosed with relapsed or refractory solid or hematologic malignancy including brain tumours 3. Currently receiving active cancer treatment or supportive and palliative care 4. Estimated survival of at least 4 months at the time of enrollment Exclusion Criteria: 1. History of cardiovascular disease, severe hepatic or renal impairment defined by alanine transaminase (ALT)/ aspartate aminotransferase (AST) more than 5x upper limit of normal (ULN), creatinine more than 5x ULN or glomerular filtration rate (GFR less than) \<60 mL/min/1.73 m273m2, unstable/unmanaged arrhythmias, uncontrolled hypertension with blood pressure above 99th centile for age or history of myocardial infarction 2. Nabilone or other cannabis-based products use (including for recreational purposes) within the past 2 weeks or planned nabilone use for the duration of their enrollment in the trial. Current use/continued use of recreational cannabis, or not willing to abstain from recreational cannabis use during the trial 3. Anyone who is pregnant or breast/chest-feeding throughout the duration of the study or has the intention to become pregnant within 3 months of study completion 4. Participation in other clinical trials that prohibit the concurrent use of cannabis 5. Children with a personal or family history of schizophrenia or psychotic disorders, substance use disorder or allergy to cannabinoids or cannabis 6. Unwilling or unable to use effective form of contraception and refrain from driving motorized vehicles (cars, motorcycles, boats, etc.) throughout the study period 7. Anyone who is currently receiving cell therapies or immune checkpoint inhibitors