Biotechnology and the Treatment of Addictive Disorders

Addiction is considered a chronic relapsing illness that is typically onset during teenage years and is followed by multiple cycles of drug use, and abstinence that are induced through interactions between genetics and environment.  The three main types of treatments are behavioral, pharmacologic and immunologic therapies.  The most recent focus has been on the development of immunotherapy for stimulants and nicotine addiction. Family and adoption studies have shown that 60% of addiction can be genetically determined. Multiple genes have become the focus of these studies, more specifically the genes that encode for dopamine receptors, the serotonin transporter gene, the norepinepherine transporter gene, and opioid receptors. 

Cocaine acts primarily as a monoamine transporter inhibitor; blocks the reuptake of dopamine, serotonin, and noradrenalin while increasing the release of glutamate. Methamphetamine, on the other hand, results in an increase of cytoplasmic concentrations of neurotransmitters.  These molecular differences are key to targeting and developing the biotechnology to treat these addictions. The prolonged use of both of these drugs can lead to a down regulation of the dopamine receptors and the uptake sites; if not treated, this could highly increase the possibility of a relapse. The creation of a vaccine or monoclonal antibody against these drugs would create a technology that would be able to remove the drug from the bloodstream before it was able to enter the brain. A vaccine must remain intact long enough to illicit antibody production, and the monoclonal antibody must remain intact long enough to bind to the drug. A vaccine is predicted to provide longer activity, but may require a large number of booster shots over the course of a few weeks to elicit a high enough titer. Monoclonal antibodies have a shorter half-life, but are favored for use in individuals with compromised immune systems.   Research has lead to the clinical development of a vaccine for cocaine, which is currently in phase II testing for efficacy and safety. Monoclonal antibodies have also been created against phencyclidine, methamphetamine, and cocaine is in preclinical development studies. For passive immunization with anti-cocaine monoclonal antibodies are also being studied, but are limited to animal studies. Overall, these trials could lead to new advancements in the treatment of addiction for multiple drugs.

Source: 

Ahmed Elkashef, Jamie Biswas, Jane B. Acri and Frank Vocci

Division of Pharmacotherapies and Medical Consequences of Drug Abuse (DPMC), National Institute on Drug Abuse

(NIDA), National Institutes of Health (NIH), Bethesda, Maryland, USA

BioDrugs. 2007, Vol. 21 Issue 4, p259-267. 9p. 1 Diagram, 1 Graph.