Page 1 - Cannabis for the Management of Pain: Assessment of Safety Study

The Journal of Pain, Vol 16, No 12 (December), 2015: pp 1233-1242
Available online at www.jpain.org and www.sciencedirect.com

Original Reports

Cannabis for the Management of Pain: Assessment of Safety Study

(COMPASS)

{
,y
z
Mark A. Ware,* Tongtong Wang, Stan Shapiro, z,x and Jean-Paul Collet for the
1
COMPASS STUDY TEAM
y
Departments of *Anesthesia, Family Medicine, Epidemiology, Biostatistics and Occupational Health, McGill
z
University, Montreal, Quebec, Canada.
Centre for Clinical Epidemiology, Jewish General Hospital, Montreal, Quebec, Canada.
x
Department of Pediatrics, University of British Columbia; Child and Family Research Institute, Vancouver, British
{
Columbia, Canada.
Abstract: Cannabis is widely used as a self-management strategy by patients with a wide range of
symptoms and diseases including chronic non-cancer pain. The safety of cannabis use for medical
purposes has not been systematically evaluated. We conducted a prospective cohort study to
describe safety issues among individuals with chronic non-cancer pain. A standardized herbal
cannabis product (12.5% tetrahydrocannabinol) was dispensed to eligible individuals for a 1-year
period; controls were individuals with chronic pain from the same clinics who were not cannabis
users. The primary outcome consisted of serious adverse events and non-serious adverse events.
Secondary safety outcomes included pulmonary and neurocognitive function and standard
hematology, biochemistry, renal, liver, and endocrine function. Secondary efficacy parameters
included pain and other symptoms, mood, and quality of life. Two hundred and fifteen individuals
with chronic pain were recruited to the cannabis group (141 current users and 58 ex-users) and
216 controls (chronic pain but no current cannabis use) from 7 clinics across Canada. The median daily
cannabis dose was 2.5 g/d. There was no difference in risk of serious adverse events (adjusted
incidence rate ratio = 1.08, 95% confidence interval = .57–2.04) between groups. Medical cannabis
users were at increased risk of non-serious adverse events (adjusted incidence rate ratio = 1.73,
95% confidence interval = 1.41–2.13); most were mild to moderate. There were no differences in
secondary safety assessments. Quality-controlled herbal cannabis, when used by patients with
experience of cannabis use as part of a monitored treatment program over 1 year, appears to have
a reasonable safety profile. Longer-term monitoring for functional outcomes is needed.
Study registration: The study was registered with www.controlled-trials.com (ISRCTN19449752).

1
Received January 25, 2015; Revised July 18, 2015; Accepted July 28, 2015. Aline Boulanger, MD, Department d’anesthesie, Universit e de Montreal,
The study was funded by the Canadian Institutes of Health Research Montreal, Quebec, Canada; John M. Esdaile, MD, Division of
(MOL-66262). M.A.W. receives salary support from the FRQS and the Rheumatology, University of British Columbia, Vancouver, British
Louise and Alan Edwards Foundation and has a research grant to his insti- Columbia, Canada; Allan Gordon, MD, Division of Neurology, Mount
tution from CanniMed. M.L. is a founding board member of Panag Pharm Sinai Hospital and University of Toronto, Toronto, Ontario, Canada; Mary
Inc, a start-up company researching topical non-psychotropic cannabi- Lynch, MD, Departments of Anesthesia, Psychiatry and Pharmacology,
noids for pain and inflammation, a medical advisor to Abide Therapeutics Dalhousie University, Halifax, Nova Scotia, Canada; Dwight E. Moulin,
researching agents to modulate the endocannabinoid system for the MD, Departments of Clinical Neurological Sciences and Oncology,
treatment of pain, and a co-investigator on a clinical trial sponsored by Western University, London, Ontario, Canada; Colleen O’Connell, MD,
Prairie Plant Systems. D.E.M. has received speaker’s honoraria and/or Department of Physical Medicine and Rehabilitation, Stan Cassidy Centre
consulting fees from Pfizer Canada, Eli Lilly Canada Inc, Janssen Pharma- for Rehabilitation, Fredericton, New Brunswick, Canada.
ceuticals, and Purdue Pharma Canada. A.B. discloses consultancies or 1526-5900
advisory boards to Bedrocan, CanniMed, Jansen, Johnson & Johnson,
Lilly, Merck, Mettrum, Pfizer, and Purdue Pharma. T.W., S.S., J.-P.C., ª 2015 The Authors. Published by Elsevier Inc. on behalf of the Amer-
A.G., C.O., and J.M.E. report no conflicts. ican Pain Society. This is an open access article under the CC BY-NC-
ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Supplementary data accompanying this article are available online at
www.jpain.org and www.sciencedirect.com. http://dx.doi.org/10.1016/j.jpain.2015.07.014
Address reprint requests to Dr. Mark A. Ware, MBBS, MRCP, MSc, A5.140
Montreal General Hospital, 1650 Cedar Avenue, Montreal, Quebec H3G
1A4, Canada. E-mail: mark.ware@mcgill.ca
1233