Growing the Evidence Base for Medical Cannabis

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With EMA’s opinion, the World back into research on vaccines for gains that have been made with insecti- Health Organization (WHO) will now malaria and other tropical diseases. In cidal nets.” convene its Strategic Advisory Group addition, it will donate 12.5 million Greenwood points out that, simi- of Experts on Immunization and the doses to PATH, an international non- larly, “in some of the HIV vaccine trials Malaria Policy Advisory Committee to profit health organization that was a there was concern that people would make a preliminary recommendation partner in developing the vaccine. stop using condoms, but that didn’t hap- on whether and how to use the vaccine Careful planning of vaccine imple- pen.” He thinks vaccine implementation by the end of October; a final WHO mentation in communities is the key requires “a proper community educa- policy recommendation is expected by to success, agree Gitani and Green- tion program” that clearly informs those November. Gitahi explains that wood. Both are concerned that the at risk, “Don’t stop using your bed net.” malaria-affected countries then must introduction of a vaccine could lead to Gitani hopes that use of the vaccine provide national regulatory approval, complacence about other prevention will lead to continued vaccine develop- which may be expedited through a measures. ment. “Following precedent in medicine WHO recommendation. “Once the vaccine is available, gov- and research, once there is one, and Procuring the vaccine is also a chal- ernments and organizations like ours once it is field-tested, the challenges are lenge for low-income countries. Glaxo- have to be very careful about the roll- easier to see. In a few years there will SmithKline has promised to make the out,” says Gitahi. “It should not be probably be vaccines that are improve- vaccine available at a reduced price — about the vaccine but about a two- or ments over this one.” — Carolyn although it hasn’t set that price yet — three-step ‘this-is-how-you-prevent- Brown, Ottawa, Ont. that would cover manufacturing costs malaria’ program. If you roll out [the plus a small return. Its profits will go vaccine] singularly, you could lose the CMAJ 2015. DOI:10.1503/cmaj.109-5132

Growing the evidence base for medical cannabis

necdotal reports of efficacy observational studies; one wants to vaporizer, as well as a placebo stripped from patients who use medi- enroll 1000 patients, another is aiming of the two main active compounds, tet- A cal marijuana aren’t enough for 3000. rahydrocannabinol and cannabidiol. to convince many physicians that can- This research is possible, in part, Leading the trial is Zach Walsh, the nabis is a viable therapeutic option, because the growing industry now wants codirector for the Centre for the but new industry-funded research in to show efficacy for its lucrative products Advancement of Psychological Science Canada may bring some science to the — and is willing to pony up the cash to and Law at UBC, who plans to recruit situation. obtain evidence. Also, there are many 40 patients who have served in the mil- Some of Canada’s 25 or so licensed more strains of cannabis to be tested than itary or as first responders, or have sur- producers under the federal medical even two years ago. Prior to 2013, there vived a sexual assault. He says existing marijuana program are investing in research to add credibility to their products. As of June 2015, Health Canada “We are catching up with patients had approved six clinical trials involv- ing patients who use dried cannabis; who have been leading the medical several others are pending approval. cannabis movement.” There are also a few large-scale observational studies, including a province- wide one in Quebec. was one government-approved producer treatments for a large number of people Medicinal marijuana is used for an and one strain of the plant. Now there are with PTSD are not effective, and many array of symptoms and conditions, hundreds of strains. are already using cannabis to ease their including multiple sclerosis, osteoar- Tilray, for example, has 55 strains in symptoms. “We are catching up with thritis, cancer and anxiety. It’s up to the its $30-million facility in Nanaimo, patients who have been leading the discretion of the physician to prescribe British Columbia. Three of those strains medical cannabis movement.” access, but the problem is the lack of will be used at the University of British Tilray is “in a unique position to be rigorous guidelines based on scientific Columbia (UBC) in Kelowna for what able to fund and support this kind of evidence. may become Canada’s first randomized research in a way that hasn’t happened Many licensed producers have been clinical trial on the use of cannabis for in North America in the past,” says collecting patient data, and some are posttraumatic stress disorder (PTSD). Philippe Lucas, the company’s vice now partnering with university-based Tilray is providing $400 000 and the president of patient research and ser- researchers to conduct large-scale dried bud for patients to use with a vices. Tilray is exploring other oppor-

studies sponsored by pharmaceutical companies, such a funding relationship engenders a risk of perceived bias. A few studies have found alternate funding — albeit still within the industry. In Ontario, a 1000-patient observational study is being supported by Can- vasRx, a medical cannabis patient education and counselling service. Prin- cipal investigator Dr. Hance Clarke says the study is similar to the Quebec registry, except that the patient fills out the questionnaire. He hopes to eventually combine data with the Quebec registry but will also look at other outcomes of using cannabis, such as quality of life, sleep and mood. Clarke, who is the director of the Pain Research Unit at the Toronto Gen-

Thom_Morri/iStock eral Hospital, says collecting broad data Licensed producers of cannabis are starting to invest in research. is the first step before designing randomized controlled trials that study dis- tunities to provide “research-grade can- The vice president of communica- ease-specific indications. “You really nabis” for studies. tions and corporate affairs at Bedrocan, need to have the comparison data to One of the eventual goals of the UBC Cam Battley, says that companies like make sure we’re sending people down study is to acquire Health Canada his are planning fairly rigorous clinical the appropriate path.” approval and an official drug identifica- programs. “We need to have more evi- A BC researcher is venturing down tion number for a cannabis product that is dence with respect to the potential bene- another research path. M-J Milloy, an shown to treat symptoms of PTSD. There fits of cannabis as well as the risks and infectious-disease epidemiologist with are currently only two cannabinoid phar- the side effects.” the British Columbia Centre for Excel- maceutical drugs approved by Health Ware hopes to recruit 2000–3000 lence in HIV/AIDS, began an observa- Canada, but the raw form of the drug, patients over the next few years, tional study in 1996 and found that either as a dried bud or oil derivative, has depending on how many doctors partic- patients with HIV who use cannabis yet to garner approval as a medicine. ipate in the 10-year observational study. daily had lower levels of the virus in Under the study parameters, the pre- their blood. The results were published Quebec’s registry scribing physician must monitor the in Drug and Alcohol Review in Novem- In 2014, Ottawa put physicians in the effects of the drug by filling out a form ber 2014. contentious position of prescribing detailing information about the disease In June, the cannabis producer, access to an untested drug. Quebec’s or condition being treated, symptoms National Green BioMed, offered Mil- college of physicians and surgeons saw and the cannabis strain and quantity. loy and UBC a $1-million grant for this is an opportunity to use these They must then follow up with the ongoing research in this area. “We were patients as the basis for a province-wide patient every three months. very lucky to receive support,” says registry and study. “In Quebec, when Ware is also leading a randomized Milloy, adding that the funding is arm’s you have to try a new medication or an controlled trial looking at vaporized can- length. “We have similar ideas with the experimental medication you can only nabis for patients with osteoarthritis of need to grow the evidence base for do that through a research program,” the knee; he started recruiting patients in medical marijuana.” says Dr. Charles Bernard, CEO of the June. “We’ve heard a lot of anecdotal The licensed producers — essen- Collège des médecins du Québec. evidence from patients with osteoarthri- tially Big Cannabis — are starting to The Quebec Cannabis Registry has tis who report that they get benefit from take advantage of their unique position arm’s-length funding from three using cannabis so we’re putting this to in the world. As Justin Dhaliwal, the licensed producers: Bedrocan Canada, the test,” he says. This trial has arm’s- CEO of BioMed, puts it: “At the end of Mettrum Ltd. and Tweed Marijuana length funding from Prairie Plant Sys- the day, if it’s a product that’s going to Inc., says Dr. Mark Ware, a pain medi- tems Inc. and CanniMed Ltd. improve the lives of Canadians, it’s our cine specialist at the Montreal General Some researchers say the biggest duty to go ahead and spend the money Hospital and the Montreal Neurological challenges around studying cannabis in research to show that evidence.” — Institute who is leading the study. “The are the lack of funding and the stigma. Shannon Lough, CMAJ idea is if we’re going to provide access Licensed producers seem to be the only we can at least learn something from it.” willing patrons, but Ware says that, like CMAJ 2015. DOI:10.1503/cmaj.109-5129