TA-CD is an active

vaccine A vaccine is a biological preparation that provides active acquired immunity to a particular infectious or malignant disease. The safety and effectiveness of vaccines has been widely studied and verified.

developed by the Xenova Group which is used to negate the effects of

cocaine Cocaine (from , from , ultimately from Quechua: ''kúka'') is a central nervous system (CNS) stimulant mainly used recreationally for its euphoric effects. It is primarily obtained from the leaves of two Coca species native to South Am ...

, making it suitable for use in treatment of

addiction Addiction is a neuropsychological disorder characterized by a persistent and intense urge to engage in certain behaviors, one of which is the usage of a drug, despite substantial harm and other negative consequences. Repetitive drug use o ...

. It is created by combining norcocaine with inactivated

cholera Cholera is an infection of the small intestine by some strains of the bacterium '' Vibrio cholerae''. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea that lasts a few days. Vomiting an ...

toxin. It works in much the same way as a regular vaccine. A large

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

molecule attaches to cocaine, which stimulates response from

antibodies An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of ...

, which destroy the molecule. This also prevents the cocaine from crossing the

blood–brain barrier The blood–brain barrier (BBB) is a highly selective semipermeable border of endothelial cells that prevents solutes in the circulating blood from ''non-selectively'' crossing into the extracellular fluid of the central nervous system where ne ...

, negating the euphoric high and

rewarding The reward system (the mesocorticolimbic circuit) is a group of neural structures responsible for incentive salience (i.e., "wanting"; desire or craving for a reward and motivation), associative learning (primarily positive reinforcement and class ...

effect of cocaine caused from stimulation of

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. Dopamine constitutes about 80% o ...

release in the mesolimbic reward pathway. The vaccine does not affect the user's "desire" for cocaine—only the physical effects of the drug.

Results

Phase III Clinical Trials showed no significant difference between users given placebo and users given TA-CD. Patients in the high antibody group had a lower drop out rate and fewer positive cocaine urine results in the last 2 weeks of the trial, but it was not significant versus the low antibody or placebo group. However at other points of the study, high antibody users had more positive urine results. This is most likely due to users trying to overcome the antibodies by taking more excessive amounts of cocaine. This vaccine does not have any effect on the underlying neurobiological cause of addiction which a possible explanation for the clinical trial failure.

Notes

References

Scientific American Mind: Cocaine Vaccine

External links

''Translational Psychiatry'' (2014) 4, e407; doi:10.1038/tp.2014.48 Vaccines against drugs Cocaine Vaccines {{vaccine-stub

Results

See also

Notes

References

External links