Center for Medicinal Cannabis Research
Also this summer, California ended state funding for the Center for Medicinal Cannabis Research (CMCR), which spent $8.7 million since 2000 for preclinical and clinical studies assessing the therapeutic value of marijuana.
CMCR’s latest study came out in May, when it published results in the Canadian Medical Association Journal on a clinical study of 30 adult patients with multiple sclerosis at the University of California, San Diego School of Medicine. The study concluded that smoked cannabis may be an effective treatment for spasticity, and did result in reduced perception of pain, though participants also reported short-term increased fatigue and adverse cognitive effects.
Igor Grant, M.D., CMCR’s director, told GEN that, while its work is finished, the center still could pursue funding or provide consultation in the future if government agencies, big pharma, or other entities wanted to further medical study of cannabis. Industry interest has largely been limited to smaller companies like Medical Marijuana and Cannabis Sciences, both publicly-traded.
“I think the next step really is to see whether the work that we’ve accomplished leads to any kind of either changes in policy, or at the very least, interest on the part of funding agencies to do this kind of work,” said Dr. Grant, who is also executive vice-chair of the department of psychiatry at the University of California, San Diego School of Medicine. “I don’t think this kind of work can be done just at the state level. I think the next phase is really larger, multisite clinical trials that are countrywide rather than specific to the state.”
That would suggest continuing the work of CMCR through a federal office, or at least a multi-site consortium. A federal office seems logical, but appears unlikely given deep division among medical officials on the therapeutic value of cannabis, as well as between supportive researchers and antidrug abuse officials opposed to any relaxation in enforcement of marijuana laws.
A Yale School of Medicine study published Aug. 21 online in the Journal of Adolescent Health gives medical marijuana foes some ammunition, linking previous use of cannabis to an increased likelihood of subsequent prescription opioid abuse during young adulthood in men and women.
Given the current election season, Washington is unlikely to embrace any change in the status quo. Yet some new research has found federal support. NIH’s National Institute of Drug Abuse is funding a third study by UC San Diego researcher Barth Wilsey, M.D., on the ability of cannabis to deliver pain relief without leaving patients stoned.
“We are actively enrolling subjects who have pain related to spinal cord injury or disease,” Dr. Wilsey told GEN.
The first study, published 2008 in the Journal of Pain, found that low (3.5%) and high (7.0%) dose tetrahydrocannabinol (THC) yielded the same pain relief, though the high dose produced poorer motor skills and reduced ability to pay attention to tasks and remember words. A second study, exploring a lower (1.29%) dose of THC, has been submitted to the same journal, with publication expected later this year or early next.
A cannabis research consortium could further explore research showing initial promise. One such topic was identified in CMCR’s MS study, led by Jody Corey-Bloom, M.D., Ph.D., director of the Multiple Sclerosis Center at UC San Diego. Dr. Corey-Bloom and colleagues concluded larger, long-terms studies are needed to confirm earlier findings and determine if lower THC doses indeed deliver benefits with less cognitive impact.
“My expectation is that for awhile the work is going to be done elsewhere because the regulatory climate and political climate doesn’t favor this research being done in the United States,” Dr. Grant said.
He said CMRC focused on spasticity, and painful peripheral neuropathy caused by conditions that include AIDS, diabetes, and some injuries. Those conditions have also been examined by others. A 2010 study by Canadian researchers led by Mark A. Ware, M.B.B.S., of McGill University found that a single inhalation of 25 mg of 9.4% THC herbal cannabis 3x daily for five days reduced pain intensity, improved sleep, and was well tolerated in people with chronic neuropathic pain. Adverse effects, however, included headache, dry eyes, burning sensation in areas of neuropathic pain, dizziness, numbness, and coughing.
Years of research has linked marijuana with therapeutic effects in people with cancer and HIV, such as lessening nausea and increasing appetite. “People with cancer who are getting proper allopathic medicine often get chemotherapy drugs, many of which cause greatly disturbing nausea and vomiting. While there are pharmaceutical drugs that deal with that, and some of them are pretty good, none of them deal with it without any serious side effects like cannabis does,” Lester Grinspoon, M.D., associate professor of psychiatry (emeritus) at Harvard Medical School, told GEN.
While some research suggests it could stop cancer—a 2007 study linked cannabis to a halt in breast cancer metastasis—a relationship between marijuana and cancer spread remains unproven, adds Dr. Grinspoon, a longtime advocate for medicinal marijuana. He has long criticized prohibitions on medical use of cannabis, citing its low toxicity, and argued that limited-use laws cannot ensure either that those patients who need marijuana can access it, or that they won’t continue using it for pleasure long after their medical condition is addressed.
“I have no problem with other people getting it. I have a problem with the deception that’s involved in it, but that’s exactly why the prohibition should go. Marijuana should be as available as aspirin,” Dr. Grinspoon said.
Generating the data to conclude whether that prohibition should go would be the greatest benefit of a multisite consortium focused on marijuana research. The challenge will be funding such a center in the absence of government or significant industry support.