DRUG'S NEW APPROACH COULD HELP ADDICTS KICK COCAINE CRAVING

European scientists have developed a drug that uses a promising new
approach to ease cravings for cocaine in addicted rats.

BP 897 is the first drug to target the "conditioning" effect of
cocaine, or the way, for example, that the mere sight of a street
corner where the addict used to buy cocaine can evoke a craving, said
Maria Pilla, a psychologist at the University of Cambridge in England
who led the study.

The only other drugs available either mimic cocaine so much that they
themselves can become addictive, or block its effects so well that
addicts overload on cocaine to deal with the pangs of withdrawal.
Whether BP 897 works in humans remains to be seen. Full-scale tests
could begin as early as next year.

The study was published in today's issue of the journal
Nature.

BP 897 eases the cravings associated with cocaine withdrawal by mildly
stimulating the brain while regulating dopamine levels, a brain
chemical that can create intense pangs for the narcotic.

This is the first drug that creates a balance in the brain to help
addicts deal with withdrawal, said Gary Aston-Jones, a University of
Pennsylvania neuroscientist who co-wrote an accompanying commentary.
Cocaine is particularly hard to kick because of its ability to
"condition" users and evoke cravings the way an old song or a whiff of
perfume can trigger a flood of memories. An addict in rehab can get a
craving for cocaine just by returning to the room where he used to
snort it.

Pilla and her colleagues reported that BP 897 helped rats addicted to
cocaine break away from the effects of conditioning. The researchers
first trained rats to give themselves cocaine through a catheter by pulling
a lever. A light was rigged to go on every time the rats did this,
conditioning them to associate the light with the high. Later, the rats
were taken off the cocaine. When researchers continued to turn the light
on, the rats were reminded of the drug and pulled the lever.

"The rat is probably going through an intense craving at this point,"
said Pierre Sokoloff, a French researcher who worked on the project at
the National Institute for Health and Medical Research in Paris. "This
is a state that simulates withdrawal."

But once scientists gave them BP 897, the rats sought cocaine only
half as much as before.

"I think this could be very significant," Aston-Jones
said.