MARIJUANA
ARTHRITIC PAIN
An upcoming clinical trial will test the safety and efficacy of using medical marijuana to manage arthritic pain.
An upcoming clinical trial from Saskatoon’s CanniMed Ltd. will test the safety and efficacy of using medical marijuana to manage arthritic pain, the first study of its kind.
Health Canada recently approved an application from Prairie Plant Systems, CanniMed’s parent company, to test the use of cannabis in patients with osteoarthritis of the knee. With scant medical evidence to back up anecdotal evidence, doctors are looking for reliable proof cannabis can help pain management, said company president and CEO Brent Zettl.
“There are clues, but they are not conclusive,” Zettl said in an interview. “Medical cannabis has been used for more than 4,000 years by human beings, but we’ve never really put our minds and effort toward proper, disciplined scientific study. We really want to look at the hard evidence that can hold up to scientific scrutiny.”
The randomized, doubleblind, placebo-controlled trial run by a third-party contractor will involve at least 60 patients and could last up to two years. It will use “vaporized” marijuana, and will test different strains with varying levels of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), two common active ingredients in cannabis.
Testing different strains — in this trial and others — could help researchers understand what ratios of THC and CBD work best for individuals and different ailments, Zettl said. Previous studies show pain receptors in the body’s joint and nervous-system tissue, immune cells and bones respond to cannabinoids in medical marijuana, he added.
Research such as this could lead to cheaper and more effective medical marijuana treatment, Zettl said.
“The only way to get there is to start at square one and prove it out,” he said. “Otherwise, what do the doctors have to go on?”
Zettl estimates one-third of Canada’s 38,000 licensed medical marijuana patients are using cannabis to treat arthritis, an ailment affecting up to 4.3 million Canadians. The use of marijuana to treat arthritis has never been tested in clinical trials, according to Health Canada’s website.
Clinical trials are needed because doctors are reluctant to prescribe a medication without fully understanding its safety and efficacy, said Bryan Salte, College of Physicians and Surgeons associate registrar and legal counsel
“One of our concerns is that (medical marijuana) hasn’t been effectively studied and to the extent that there are appropriate studies it’s very helpful to add to the body of evidence that would support or refute the use of marijuana for certain medical conditions,” Salte said.
He couldn’t comment on the specifics of the CanniMed study, but Salte said it could be helpful, whatever researchers find.
“If hypothetically it was found there is no benefit, or more risk than benefit, then we would have the basis to say to physicians this is bad medicine,” he said.
“On the other hand, if the evidence does come out that supports the use of medical marijuana, that’s an additional piece of information that should cause physicians to think seriously about using that as a possible treatment for arthritic pain in the knees.”
Before launching CanniMed, Prairie Plant Systems was the sole producer of cannabis for Health Canada under the old medical marijuana regulations. The rules changed on April 1, allowing other businesses, with Health Canada approval, to sell directly to patients with doctor prescriptions for cannabis. Currently, 13 companies across Canada are approved retailers.