Cannabis touted as opioid option, more data needed
Seeking clarity ‘on efficacy as well as safety’
As doctors struggle to contain the opioid crisis in Canada, a new study on chronic pain suggests that medicinal cannabis may offer alternative relief.
Funded by Toronto-based Apollo Applied Research, it tracked the experiences of more than 300 chronic pain patients over a period of three years.
More than one- third of participants had been prescribed a regimen of opioids, such as oxycodone and fentanyl, which come with a high risk of addiction and potentially fatal overdose.
Dosages and deliver y mechanisms varied for each patient, but surveys of participants in Apollo’s study — observational in nature rather than experimental — found that 45 per cent of opiate users reduced their dos- age after starting cannabis treatment, and another 35 per cent stopped taking opiates altogether.
Medicinal cannabis, which generally lacks the “high” of recreational pot because of lower levels of THC, is most often prescribed for low-level pain management, particularly for patients with chronic pain. The drug is also prescribed for glaucoma, posttraumatic stress disorder ( PTSD), Parkinson’s- related tremors and for pain stemming from irritable bowel syndrome and Crohn’s disease.
But Health Canada only approved its first experimental trial in 2015 — a randomized, double- blind study by researchers at McGill University on the efficacy of cannabis treatment for osteoarthritic knee pain.
Last month, a group of 10 medical professionals published a peer-reviewed guideline in the journal Canadian Family Physician, suggesting limited medical cannabinoid use because of “a lack of highlevel research.”
“I think we’re in a desperate need for information at the moment,” says Mark Ware, a renowned pain specialist and associate profes- sor at McGill who took part in the osteoarthritis study. “Obviously, we need information on both efficacy as well as safety. Does the drug work for a particular condition? Is it safe for patients to use?”
Long-term overuse of marijuana has been linked to decreased memory capacity and impaired cognitive functions, as well as bronchitis. Rigorous scientific evidence is still needed around potential health benefits.
For Apollo’s study, each participant was given a treatment plan by their own doctor. Researchers then had them fill out standardized surveys (created using certified methodologies for scoring subjective experience) to see whether they had any reductions in the intensity and frequency of pain, as well as other improvements to quality of life.
Overall, participants reported a 20 per cent reduc- tion in the severity of symptoms, and a dramatic reduction in opiate use. “In total it was close to about 75 per cent to 80 per cent of (opioid users) that stopped or reduced their opioid use,” says Genane Loheswaran, the company’s director of clinical research.
Apollo’s researchers have also been looking into cannabis effects among patients suffering from post-traumatic stress disorder, and Lohes- waran says the results there are similarly promising.
But neither study has been published by a peer-reviewed journal at this stage. And Apollo Applied Research, which has spent in excess of $1 million on this study, earns a profit from its relationship with licensed cannabis producers — it’s the science division of Apollo Cannabis Clinics, which runs a national referral service for medical marijuana and two dedicated clinics in Toronto.
Company president Bryan Hendin, who began researching cannabis efficacy in 2013 as a way of bringing legitimacy to the field, doesn’t shy away from perceived conflict of interest: “If you look at it for Pfizer, to get a medication out, they’re not asking someone else to pay for their clinical trial,” he says. “At the end of the day, this data will speak for itself.”
Ware’s own research on osteoarthritis pain was funded by industry producers Prairie Plant Systems and CanniMed. He believes what’s more important is that studies are reviewed by an ethics board and that findings are submitted for peer review within a credible journal.
Apollo has submitted its chronic pain study for peer review. Whether it holds up to scrutiny remains to be seen. But Ware says there are strong signals that cannabis has the potential to influence opioid use patterns in chronic pain.
“I think we still have got a long way to go before we can make recommendations,” he says, “but it’s an area that deserves very serious and very careful attention.”
I THINK WE STILL HAVE GOT A LONG WAY TO GO BEFORE WE CAN MAKE RECOMMENDATIONS, BUT IT’S AN AREA THAT DESERVES VERY SERIOUS AND VERY CAREFUL ATTENTION.
— MARK WARE, PAIN SPECIALIST AND ASSOCIATE PROFESSOR AT McGILL UNIVERSITY
Prescription pills containing oxycodone and acetaminophen.