February 28, 2001
By MARK ROBICHAUX
Staff Reporter of THE WALL STREET JOURNAL
After 10 years of searching, University of Mississippi Professor Mahmoud El Sohly thinks he has a new way to quiet opponents of marijuana as medicine: a pot suppository. Designed to ease post-chemotherapy nausea, among other conditions, its best feature may be what it doesn't do. "There is no high," says Dr. El Sohly.
Whether the Food and Drug Administration ever will approve his drug, which he has tried out on animals and human subjects, is hard to predict, pending clinical trials sure to cost millions he doesn't yet have. He's trying to interest drug companies.
For patients turning to marijuana for relief from a symptom such as nausea, the high may be an unwanted side effect. To the government, it's illegal substance abuse. So in labs around the world, researchers like Dr. El Sohly are attempting to create marijuana pills, aerosols, injections and sprays that don't create a buzz. Some are tweaking molecules, while others are in the greenhouse crossbreeding plants.
One and the Same
What makes the task so tricky is that the same ingredient that appeals to pot smokers -- tetrahydrocannabinol, or THC -- is what holds promise as a medicine. Of the 400 or so chemicals found in the hemp plant, more than 60 are so-called cannabinoids, and none is more psychoactive than THC.
Some challengers in the race are already claiming victory. A tiny New York City firm called Atlantic Technology Ventures Inc. is waiting to unveil a synthetic compound called CT-3 -- claimed to be THC without the high. Sumner Burstein, a professor at the University of Massachusetts department of biochemistry and molecular pharmacology, developed the drug as a pain-reliever and says it is nonpsychoactive: "I took one myself -- no mental aberrations." At least four years of testing await the drug, which the company hopes to market one day as a "super-Tylenol."
Prof. Audra Stinchcomb of the Albany College of Pharmacy in New York is testing in the lab a patch designed to relieve the side effects of chemotherapy in cancer patients. Key to this effort's success is the rate of "transdermal" intake of the drug -- too little and patients feel no effect; too much and they get giggly. She attaches synthetic-THC patches to pieces of skin left over from plastic surgeries to evaluate absorption.
In southern England, three-year-old GW Pharmaceuticals is hybridizing cannabis plants to breed out psychoactive agents in some cases, to increase THC in others. The company, which has a unique license from the government of the United Kingdom, grows 50,000 plants, producing 15 tons of marijuana a year for medical research. "We have a perfect factory growing one cannabinoid or another," says founder and chairman Geoffrey Guy.
While most other research involves extracting a single THC molecule from cannabis and modifying it, Dr. Guy hopes to use the pharmaceutical extracts of the entire plant. One way to reduce psychotropic effects, says Dr. Guy, would be to increase the content of other helpful cannabanoids besides THC, such as cannabidiol, or CBD, which seems to minimize the high.
GW's first product, which could hit U.K. markets as a pain-reliever by 2003: a device the size of a mobile phone that allows a daily dose of a prescribed number of squirts under the tongue of cannabis extract, containing both CBD and THC. The dispenser won't allow extra squirts. "We have chaps [in tests] using heavy machinery ... some are teaching," says Dr. Guy. "They aren't sitting in a corner high as a kite."
At London's Imperial College, researchers are testing a THC-based drug that circumvents the brain entirely -- delivered by a spinal injection. Though it is too early for human trials, researchers are hoping to find that THC derivatives are more effective than morphine for relieving pain from spinal-cord injuries.
Individual scientists, academic labs and small drug firms are pushing the research hardest, largely because big drug companies have traditionally been leery of the cost and political problems associated with marketing marijuana as medicine. Also, because cannabis is a natural product in the public domain, it can't be patented. Today, the only prescription-based medical marijuana available in the U.S. is Marinol, a synthetic cousin of THC sold and marketed by Unimed Pharmaceuticals Inc. Though approved as a nausea drug in 1985, and as an appetite-stimulant for AIDS patients in 1992, it can induce a drug high. Sales today reach an estimated $20 million annually.
Big companies are starting to get interested in the field. "We see them -- Pfizer, GlaxoSmithKline, Novartis -- all the time at the meetings of the society now," says Roger Pertwee, a professor at the University of Aberdeen in the U.K. and secretary of the International Cannabinoid Research Society, a group of medical and academic researchers. "They never came in the past." Spokesmen for all three companies said they wouldn't dispute that assertion but also wouldn't confirm that they have had people at meetings. Kate Robins of Pfizer Inc. said, "Our job is to cure diseases. We have 12,000 researchers. We leave no stone unturned."
In 1999, the Institute of Medicine, a branch of the National Academy of Sciences, made the strongest case to date for cannabis as a potentially effective treatment for nausea, AIDS-related appetite loss, glaucoma, multiple sclerosis and other ailments. Its compilation of studies, "Marijuana and Medicine: Assessing the Science Base," concluded that cannabinoids have "potentially far-reaching therapeutic applications."
Recent findings suggest that THC holds more potential as a painkiller than anyone ever guessed. Discoveries that the body produces its own cannabinoids that bind with receptors located in the brain and elsewhere lead scientists to believe THC could affect nerve impulses between cells in precise ways.
"In war, some men lose limbs and they don't feel pain because the body can turn pain off," explains J. Michael Walker, a professor at Brown University and current president of the cannabis research society. New research suggests that "when you activate parts of the brain that turn pain off, it causes the release of cannabinoids. Can cannabinoids suppress pain pathways? It's a very exciting science question."
Some scientists remain skeptical. "Anecdote is not evidence," declares Alan I. Leshner, director of the National Institute on Drug Abuse, which funds research on addiction. "There is still very little controlled clinical research on cannabis that demonstrates medical benefit."
Prof. Burstein, of the University of Massachusetts, says other professors often "get a big grin on their face" when he speaks about his marijuana research.
"They ask, 'Did you
remember to bring the brownies?' "