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.

Cocaine

The social implications of cocaine abuse in the U.S. have been the subject of extensive media coverage during much of the 1980s and most of the 1990s. As a result, the general public has acquired some of the terminology associated with the cocaine usage. “Smoking crack” and “snorting coke” are terms that have become well understood in the American culture from elementary school through adulthood. However, there are facts associated with this drug which are not well understood by the general public.

There are documented historical aspects associated with coca and cocaine abuse which go back 500 years. Recognizing some of these historical aspects enables the public to place today’s problem in perspective. Cocaine addiction has been with society for well over 100 years.

There are four areas of interest this section will address: (1) Where does cocaine come from? (2) How is cocaine isolated from the coca plant? (3) What does one take into the body from cocaine purchased on the street? (4) How does the chemist analyzing the drug identify and distinguish between the different forms of cocaine?

Cocaine is a Schedule II controlled substance. The wording in Title 21, Part 1308.12(b)(4) of the Code of Federal Regulations states:

Coca leaves (9040) and any salt, compound, derivative or preparation of coca leaves (including cocaine (9041) and ecgonine (9180) and their salts, isomers, derivatives and salts of isomers and derivatives), and any salt, compound, derivative, or preparation thereof which is chemically equivalent or identical with any of these substances, except that the substances shall not include decocanized coca leaves, or extractions of coca leaves, do not contain cocaine or ecgonine.

It is significant that the term “coca leaves” is the focal point of that part of the regulation controlling cocaine. The significance of this fact will become more apparent as this discussion progresses.