Paris, France: European regulatory authorities have approved the prescription use of the cannabinoid receptor antagonist SR 141716A, to be marketed by Sanofi-Aventis Pharmaceuticals as an anti-obesity drug under the trade name Acomplia (Rimonabant). The cannabinoid blocker, to be sold as an oral 20 milligram pill, is the first cannabinoid antagonist to be approved for human consumption.
Acomplia will initially be available by prescription in the United Kingdom, though the drug is not expected to become widely available in that country until after it receives market approval from Britain’s National Institute for Health and Clinical Excellence (NICE), a process that could take up to two years. Sanofi-Aventis is also planning product launches of Acomplia in Demark, Ireland, Germany, Finland, and Norway later this year.
In clinical trials, daily use of Acomplia led to an average 14 pound decrease in subjects’ weight after one year and an additional loss of 2.4 pounds the second year. However, subjects typically regained the weight after they ceased using the drug. Commonly reported side effects of the drug include depression, anxiety, and nausea. More than 15 percent of subjects who tried Acomplia discontinued its use because of the drug’s adverse effects.
Acomplia blocks the natural binding of endogenous cannabinoids to the neuronal CB1 receptors, causing subjects to lose their appetites. It is not known whether Acomplia blocks exogenous cannabinoids such as THC from binding to the cannabinoid receptors or whether the body moderates its production of endogenous cannabinoids in patients taking Acomplia. Because the endocannabinoid receptor system is involved in the regulation of several primary biological functions including appetite, body temperature, mood elevation, blood pressure, bone density, reproductive activity, learning capacity, and motor coordination some experts are concerned that the long-term use of Acomplia may eventually contribute to significant adverse health effects.
NORML Executive Director Allen St. Pierre called the regulatory approval of Acomplia ironic.
“Despite decades of clinical and anecdotal reports demonstrating the therapeutic safety and efficacy of inhaled, natural cannabinoids, European regulators have instead rushed to approve a drug that is essentially ‘anti-marijuana’ without giving serious thought to its potential health and safety risks if used long-term,” St. Pierre said.
Sanofi-Aventis is also seeking US approval for Acomplia to market the drug as both a weight loss pill and as a smoking cessation agent. Though the US Food and Drug Administration declined to approve the drug this past February, the company is hopeful that it will receive US approval by 2007.
Sales of Acomplia in Europe are expected to generate $3 billion dollars in revenue, according to company officials. Sanofi-Aventis is the third largest pharmaceutical company in the world.
For more information, please contact Allen St. Pierre, NORML Executive Director, or Paul Armentano, NORML Senior Policy Analyst, at (202) 483-5500.