Pubdate: Wed, 18 Jan 2006 Source: Anderson Valley Advertiser (CA) Column: Cannabinotes Copyright: 2006 Anderson Valley Advertiser Contact: http://www.theava.com/ Details: http://www.mapinc.org/media/2667 Author: Fred Gardner Bookmark: http://www.mapinc.org/pot.htm (Cannabis) Bookmark: http://www.mapinc.org/find?323 (GW Pharmaceuticals) COMES NOW ACOMPLIA Even before Eli Lilly began selling Prozac in December, 1988, the company was selling the concept of "clinical depression" (the alleged disease that Prozac allegedly cures, or helps people cope with. Lilly also began educating doctors and the public about "selective serotonin reuptake inhibition," the mechanism by which Prozac allegedly works. Sanofi-Aventis, the world's third-largest drug company, is pursuing a similar strategy as it awaits approval to market a drug called Acomplia to treat a condition called "metabolic syndrome." In recent years Sanofi has been educating doctors and the public about "metabolic syndrome" (high glucose levels, obesity, and other risk factors for diabetes) and Acomplia's mechanism of action, which involves blocking the body's own (endo-) cannabinoid system. Acomplia is the drug formerly known as Rimonabant. Before that it was known as SR141716, the SR standing for "Sanofi Recherche." It was developed in 1995 as an "antagonist" drug for use by researchers studying the endocannabinoid system. (By administering a drug that blocks specific receptors, scientists can infer the receptors' functions.) Sanofi soon realized that its cannabinoid antagonist could be marketed as a weight-loss drug, and undertook a series of clinical trials. Approval by the FDA and/or the European Medicines Agency is pending. The New Scientist devoted a feature story to Acomplia Dec. 10, that undoubtedly convinced some readers to buy Sanofi stock. "If what has been made public from the clinical trials is anything to go by," writes Diane Martindale, "rimonabant has almost miraculous powers, helping people to control their appetites, shrink their waistlines and banish many of the metabolic problems associated with being too fat. And that's not all. Rimonabant has also been successfully tested as an aid to quitting smoking and might even be useful in treating alcoholism and other addictions... No wonder many industry analysts are backing it to become the first blockbuster drug of the 21st century... "All four obesity trials are now complete. Sanofi has only published one set of results, from the halfway point of a two-year European study involving 1507 volunteers, but if the results are replicated in all the trials, the drug looks like a winner... "Investment banker JP Morgan predicts that sales will reach $5 billion a year by 2010, which would make rimonabant one of the highest-grossing drugs of all time. Curiously, however, Sanofi-Aventis does not intend to market rimonabant for weight-loss or smoking cessation, preferring to cast it as a heart medication on the back of the cardiovascular benefits of curbing metabolic syndrome and giving up cigarettes. Nor is Sanofi interested in trying to get the drug approved for alcohol abuse or other drug addictions, despite successful tests in alcoholic rats. This could make good business sense, since US health insurance companies rarely pay for anti-obesity drugs but will cover the cost of cardiovascular medication. And the regulatory agencies tend to be extra critical of weight-loss medications. But even if it is marketed only as a medication for heart disease, the drug could be huge." Martindale quotes weight-loss specialist Louis Aronne singing Acomplia's praises in a familiar cadence: 'This is the first effective treatment for the metabolic syndrome with weight loss as a side effect,' he says. (Just as Prozac was the first effective treatment for clinical depression without fatal overdose as a side effect.) Another expert, Jason Halford, is quoted: "'This is good news for heart disease,' he says (sic). 'Cardiologists are looking for drugs to manage smoking and obesity, two things they can't do with existing heart disease drugs.'" Things have changed since Prozac was introduced -the corruption of the system by which drugs are evaluated and approved has been widely exposed- and the New Scientist's Acomplia piece devotes some space to those expressing misgivings. "People in the obesity trials tended to reach a plateau after about 34 weeks, and if they stopped taking the drug, they regained all the lost weight," Martindale notes. "Sanofi-Aventis thinks that people will be able to continue taking the drug indefinitely, but some obesity experts are wary." And there are those who might not want to take a drug for the rest of their lives. Also on the adverse side of the ledger: Acomplia was found to increase blood pressure even as it facilitated weight loss. Some 40 per cent of Sanofi's test subjects dropped out during the first year of the obesity trials. "Some complained of nausea, diarrhea, vomiting, dizziness and headaches, as well as mood disorders including anxiety and depression," according to the New Scientist. Tod Mikuriya, MD, fears that Acomplia may induce seizures and exacerbate or cause tumors, among other adverse effects. Last week the Berkeley-based psychiatrist was browsing the web for continuing medical education classes (doctors are obligated to earn 25 credits over four years) and came upon an expensively produced presentation on "The Endocannabinoid System: A Novel Therapeutic Target for the Management of Multiple Cardiovascular Risk Factors." The class consisted of talks by Sanofi-funded doctors at a Sanofi-funded symposium, culminating in a strong pitch for rimonabant. Instead of applying for his 2.5 credits, Mikuriya fired off an email to the FDA warning that, theoretically, blocking the CB1 receptor system could bring on or make worse every medical condition for which cannabis provides relief. He included the master list of conditions that California patients have reported treating efficaciously with cannabis. Mikuriya got a reply saying that his concern had been forwarded to a review officer (none other than David Graham, MD, the brave FDA staffer who defied his bosses to tell the Senate the truth about Vioxx! Kinder, Gentler Antagonist? GW Pharmaceuticals has bred a plant strain rich in THCV (tetrahydrocannabivarin) that it hopes will provide a natural antagonist drug that doesn't have the liabilities of Sanofi's synthetic. GW is the British pharmaceutical company that in 2005 won conditional approval in Canada to sell a plant extract called Sativex as a treatment for pain caused by multiple sclerosis. Anecdotal evidence from seed collectors suggested that strains high in THCV had notably "clearer" and "faster" effects than high-THC strains, and GW decided to sponsor a pharmacological study by Roger Pertwee, MD, of the University of Aberdeen. Pertwee determined that THCV strongly Antagonizes anandamide -one of the body's own cannabinoids- while hardly antagonizing the plant cannabinoid THC! "The discovery that THCV was a neutral antagonist at the CB1 and then the CB2 receptor was a complete surprise," according to GW chairman Geoffrey Guy, MD. "It is therefore unlikely to be psychoactive at all in humans. Even more intriguing was the fact that THCV antagonizes THC far less than endogenous (anandamide) or synthetic cannabinoids." Apparently the cannabis plant contains and makes available to the body a choice of drugs and the body uses those it needs to achieve a balanced state (homeostasis). 3If the body is producing endocannabinoids in excess, it can use the plant cannabinoid THCV to achieve homeostasis,2 Guy observes. 3If the endocannabinoid system needs a boost, the THC provides it (while the THCV shuts down the endocannabinoid system, giving it a rest as it were). The key to relief, apparently, is not high cannabinoid levels but proper gradients.2 GW has developed a strain with a cannabinoid content of 85% THCV and 15% THC. (It may not be possible to have a plant that expresses 100% of its cannabinoid content as THCV.) Guy says, "the possibility exists (yet to be demonstrated) that the extract might inhibit the endogenous cannabinoids whilst maintaining basic cannabinoid tone through the effects of THC (albeit less potently than when unopposed by THCV). More pharmacology is underway and we hope to take this extract into man this year." GW's goal is a preparation that curbs hunger but does not drive tumor formation, exacerbate MS cases, lower seizure thresholds or produce anxiety and depression. "You want a drug that takes the edge off, not one that hits you like a ton of bricks," says a GW researcher who hopes that Sanofi's campaign to educate doctors and the public about metabolic syndrome will create a market for his company's kinder, gentler cannabioid-antagonist drug. - --- MAP posted-by: Jay Bergstrom