Two vaccines for cocaine addiction
The developers of both vaccines are Cornell University scientists working under the leadership of Ronald Crystal. They believe that over time, their vaccines may become the first representatives of a new generation of drugs to combat addiction, the mechanism of action of which is based on targeted stimulation of the body's immune system. The result of such stimulation is the synthesis of antibodies that attach to potentially dangerous molecules (in this case, cocaine molecules) and, thus, label them for absorption by specialized immune cells and excretion from the body.
The active ingredient of the first, so-called "active" vaccine is harmless viral proteins that provide familiarization of the immune system with cocaine-like molecules. The immune system recognizes the combination of a viral protein and a target molecule as a threat and begins to produce cocaine-specific antibodies.
To assess the vaccine's ability to prevent cocaine from entering the brain, monkeys were injected with a marker compound that binds to nicotine receptors in brain tissue. During positron emission tomography, the brain of cocaine-using unvaccinated animals gave a rather weak signal due to the fact that some of the receptors were blocked by cocaine molecules. At the same time, the brains of the animals who received the vaccine injection shone brightly due to marker molecules bound to cocaine receptors. This effect persisted for at least four months after vaccination.
The second, "passive" vaccine uses a different type of virus to inject genetic material into liver cells. After vaccination, liver cells begin to express proteins encoding the genetic material of the virus, including the sequence of antibodies against cocaine encoded in it.
Subsequently, the same thing happened in the body of mice vaccinated with this gene therapy approach as in the body of monkeys vaccinated with the first type. The antibodies bound to cocaine in the bloodstream, which prevented it from entering the brain. At the same time, the animals did not fall into drug intoxication after using cocaine: they behaved quietly instead of rushing around the cages. The effect of the vaccine persisted for at least 17 weeks.
The researchers are currently testing the toxicity of both vaccines on animals and hope to start a clinical trial of an active vaccine within the next year. If at least one of the developed approaches is successful, it can be used as a basis for creating vaccines for the treatment of heroin, nicotine and other addictions.
The results of experiments with the "active" vaccine were presented on June 12 at the annual congress of the Society of Medical Radiology, held in Miami Beach.
Article by Rosenberg et al. AAVrh.10-Mediated Expression of an Anti-Cocaine Antibody Mediates Persistent Passive Immunization That Suppresses Cocaine-Induced Behavior is published in the journal Human Gene Therapy.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of LiveScience: How Cocaine Vaccines Could Cure Drug Addiction.
26.06.2012