Development of vaccines to help treat drug dependence.

The social and economic consequences of drug addiction are immense. Although many methods are adopted to treat addiction, including therapeutic intervention and counseling, the long-term success rate has been limited and there continues to be a need for more effective treatments. A novel approach that has sparked a significant degree of interest recently is the use of vaccines designed to raise specific antibodies against drugs of abuse. Antibodies that prevent addictive substances crossing the blood-brain barrier may prove to be an effective mechanism that will help prevent relapse during efforts to abstain from the drug. Proof-of-principle for this approach has been established in numerous animal models. Currently a cocaine vaccine is in phase II clinical trials and, more recently, two vaccines to nicotine have entered phase I trials. Key efficacy trials are required to establish the true potential of these therapeutic vaccines.