An experimental anti-cocaine vaccine reduced cocaine use in a recent clinical trial. The result is the first successful demonstration of a vaccine against an illegal drug of abuse.
Like vaccines against infectious diseases, the anti-cocaine vaccine stimulates the immune system to produce antibodies. These attach to cocaine in the blood and prevent cocaine from passing into the brain.
Researchers funded by NIH randomly assigned 115 patients to receive either the anti-cocaine vaccine or an inactive vaccine. The patients received 5 vaccinations over a 12-week period. All attended weekly relapse-prevention therapy sessions. Their blood was tested for antibodies to cocaine, and their urine for signs of cocaine use.
The participants with the highest antibody levels had significantly more cocaine-free urine samples (45%) than those who received the inactive vaccine or those who received active vaccine but had low levels of antibodies (35%). The researchers saw no serious side effects.
While the vaccine didn’t lead to complete abstinence, the researchers say the results are meaningful. Reducing cocaine use can significantly improve an abusers’ quality of life.
“The results of this study represent a promising step toward an effective medical treatment for cocaine addiction,” says Dr. Nora Volkow, director of NIH’s National Institute on Drug Abuse. “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.”