A Vaccine for Addiction: For the 1.9 million cocaine users in the US alone, addiction is a problem for which no FDA-approved therapy exists. Now, a vaccine effective on primates is ready for human trials.
● Cocaine blocks the recycling of dopamine so that it accumulates in the brain, prolonging and amplifying signaling in reward centers to generate that pleasurable “high”. Over time, dopamine receptors (pink buckets in image) decrease, requiring higher doses of cocaine and causing a vicious cycle of dependence. There are drugs that interfere with cocaine’s action but they alter these important signaling pathways and have side effects.
● The Cocaine Vaccine triggers an immune response to the drug, that “eats up the cocaine in the blood like a little Pac-Man before it can reach the brain,” says Dr. Ronald G. Crystal, of Weill Cornell Medical College. The trick is to chemically link a cocaine analog to the common cold virus so that the body is tricked into making antibodies. The virus is crippled and cannot cause an infection. To feel the drug high that cocaine users seek to achieve, at least 47 percent of the dopamine transporter needs to be occupied by cocaine. The vaccine reduces this occupancy to 20% so the user fails to achieve the cocaine high.
● Free PubMedCentral Read: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3048190/
● Image: Left, Mechanism of Cocaine at the Synapse (http://goo.gl/ZCk4K), Right, Effect of anti-cocaine vaccine on non-human primate brain, taken from Maoz et al., Neuropsychopharmacology. 2013 May 10. doi: 10.1038/npp.2013.114. Epub ahead of print)