Coacain Vaccine Closer to Reality

Nothing says drug addiction more than a needle and syringe. But that's exactly what a team of U.S. researchers believes can help cocaine users kick their menacing habit.

Two Baylor College of Medicine scientists based in Houston have developed a cocaine vaccine that creates antibodies that bind to the drug and prevent it from travelling from the bloodstream to the brain. The vaccine stimulates the immune system to attack cocaine molecules after the drug is consumed. The system, which is not able to recognise the drug naturally, can not produce antibodies against them.

Unable to penetrate the brain, the drug can produce no high.

If the vaccine makes it through regulatory hurdles, it would be the first medication approved to treat cocaine addiction.

“It certainly is a way of combining immunology that had not been used before,” Tom Kosten, a professor of psychiatry and neuroscience at Baylor, said in a telephone interview yesterday. “We had always thought of altering the brain as a way to prevent drug abuse. This way, the drug never gets into the brain to begin with.”

Drug addiction treatment has largely been psychiatric counselling and 12-step programs. Dr. Kosten said that won't go away – any approved vaccine would be complementary to behavioural therapy.

“If it's approved in the U.S., then getting approval in Canada won't be that difficult,” he said, adding that, if all goes well, a cocaine vaccine could be available in the United States in four years.

About 50 pharmaceutical options have previously been explored for cocaine addiction.

Sources of Cocaine

Cocaine is just one of the alkaloidal substances present in the coca leaf. Cocaine is extracted from the leaves of the coca plant. The primary of source of cocaine imported into the U.S. is South America, but the coca plant also grows in the Far East in Ceylon, Java, and India. The plant is cultivated in South America on the eastern slopes of the Andes in Peru, and Bolivia. There are four varieties of coca plants — Erythroxylon coca var. coca (ECVC), Erythroxylon coca var. ipadu, Erythroxylum novogranatense var. novogranatense, and Erythroxylum novogranatense var. truxillense.1–3 ECVC is the variety that has been used for the manufacture of illicit cocaine.

While cultivated in many countries of South America, Peru and Bolivia are the world’s leading producers of the coca plant. Cocaine is present in the coca leaves from these countries at dry weight concentrations of from 0.1 to 1%. The average concentration of cocaine in the leaf is 0.7%. The coca shrub has a life expectancy of 50 years and can be harvested three or four times a year.

The method of isolating cocaine from the coca leaf does not require a high degree of technical expertise or experience. It requires no formal education or expensive scientific equipment or chemicals. In most instances the methodology is passed from one generation to the next.