TRIALS TO START FOR COCAINE 'VACCINE'

SCIENTISTS are about to embark on trials of the first vaccine against
cocaine addiction. Once inoculated, patients will be unable to feel
any of the effects of cocaine, no matter how much they take, because
the drug will be neutralised by the immune system.

"We have done the work on animals and we are moving into the clinic
later this year," said Professor Kim Janda of The Scripps Research
Institute in California. "We plan to work with patients, possibly at a
hospital in France, by the autumn of this year.

"We are really convinced it will have a big impact. One of the
problems with cocaine is that people often want to give up but keep
having relapses. With a vaccine and a booster every few months, they
can stay off it. We are looking at an antibody to nicotine as well."

Vaccines are used to educate the immune system so that when a virus,
such as measles for example, enters the body it is not allowed to
cause disease. Antibodies recognise that the virus is a foreign body
and destroy it. Scientists at the Scripps Institute have adopted this
approach in the design of their treatment.

In the Scripps vaccine small molecules of cocaine are attached to a
large protein molecule that antibodies recognise as foreign. The
antibodies then break them down before they reach receptors in the
brain. "Imagine this cocktail being like a second world war mine with
spikes on," said Janda.

"The spikes are the cocaine and the ball is the large molecule
protein. We are able to disguise it in such a way that the immune
system thinks it is different and foreign and produces antibodies to
remove it."

A second so-called passive vaccine has also been developed, where the
antibodies are created outside the body and then injected. This
approach allows a larger number of antibodies to be active.

"If you had the active and the passive vaccine and you took cocaine,
there would be no effect. You would not know you had taken cocaine,"
said Janda, who has completed the first large study on animals to show
the procedure works.