The NIH reported on a NIDA study noting that it “suggests harnessing the immune system against cocaine addiction may prove effective.” In a clinical trial supported by the National Institute on Drug Abuse (NIDA), a component of the National Institutes of Health, immunization with an experimental anti-cocaine vaccine resulted in a substantial reduction in cocaine use in 38 percent of vaccinated patients. The study, published in the October issue of the Archives of General Psychiatry, “is the first successful, placebo-controlled demonstration of a vaccine against an illicit drug of abuse.” NIDA Director Dr. Nora Volkow commented, “The results of this study represent a promising step toward an effective medical treatment for cocaine addiction. Provided that larger follow-up studies confirm its safety and efficacy, this vaccine would offer a valuable new approach to treating cocaine addiction, for which no FDA-approved medication is currently available.” NIH said that “like vaccines against infectious diseases such as measles and influenza, the anti-cocaine vaccine stimulates the immune system to produce antibodies. Unlike antibodies against infectious diseases, which destroy or deactivate the disease-causing agents, anti-cocaine antibodies attach themselves to cocaine molecules in the blood, preventing them from passing through the blood-brain barrier. By preventing the drug’s entry into the brain, the vaccine inhibits or blocks the cocaine-induced euphoria.”

http://www.nih.gov/news/health/oct2009/nida-05.htm