Cannabis as a Complementary Treatment in Multiple Sclerosis

Inclusion Criteria: Participants must meet the following criteria: 1. Diagnosed with MS (any subtype), for at least six months, by a MS neurologist, according to the recent version of the McDonald criteria; 2. Spasticity due to MS of at least one-month duration and not relieved with current therapy, at a level of 4 or more on the numerical rating scale (NRS); 3. Stable dose of standard therapies for at least 30 days prior to the screening visit and willingness for these to be maintained for the duration of the study; 4. Aged 21 years or older; 5. Ability (in the investigator's opinion) and willingness to comply with all study requirements; 6. Ability to speak and read French or English (grade-nine level of language required); Exclusion Criteria: Participants will be excluded if any of the following criteria are met: 1. Concomitant disease with symptoms of spasticity, or that may have influenced their level; 2. Received a botulinum toxin injection within four months prior to the screening visit or unwillingness to stop receiving botulinum toxin injections for the duration of the study; 3. Use of cannabis or cannabinoid-based medications within 7 days of study entry and unwillingness to abstain for the duration of the study; 4. History of schizophrenia, other psychotic illness or other significant psychiatric disorder other than anxiety or depression associated with their underlying condition; 5. Alcohol or substance use disorder other than nicotine; 6. History of epilepsy or recurrent seizures; 7. Hypersensitivity to cannabinoids or any of the excipients of the study medication; 8. Clinically relevant cardiac dysfunction within the last 12 months or had a cardiac disorder that, in the opinion of the investigator would put the subject at risk of a clinically relevant arrhythmia or myocardial infarction; 9. Impaired renal function i.e., serum creatinine clearance lower than 50 ml/min; 10. Significantly impaired hepatic function, at visit 1, in the investigator's opinion and/or had liver function tests of equal to or greater than three times the upper limit of normal; 11. Pregnancy or breastfeeding; 12. Men with history of fertility problems and who plan to conceive at any time in the future; 13. Any participant who plans to conceive either at screening or while enrolled in the study; 14. Inability (or unwillingness) of women of childbearing potential and men to use a medically acceptable form of contraception throughout the study duration; 15. Inability to use a medically acceptable form of contraception throughout the study duration; m) any other significant disease or disorder which, in the opinion of the investigator, may either put the subject at risk because of participation in the study, may influence the result of the study, or the subject's ability to participate in the study; 16. Intention to travel internationally, or to donate blood during the study.