VACCINATION AGAINST EFFECTS OF PCP, COCAINE MAY BE POSSIBLE

NEW ORLEANS -- Designer antibodies may someday be used to immunize
people against cocaine and other drugs to block the rush that users
crave.

If these vaccines fulfill their promise, they could revolutionize
emergency treatment for PCP and amphetamines. And though they won't
cure addiction, they could also help people who want to kick the
habit, researchers say.

"Our goal would be to protect against the sudden unexpected urge to
use, so that if the patient used it, he wouldn't get the effects,"
said Dr. Michael Owen, a pharmacologist at the University of Arkansas
for Medical Sciences who hopes to begin tests this year on a PCP
overdose treatment.

The illegal drugs all have molecules so tiny they sneak unnoticed
through the body's immune system. To create antibodies, researchers
must hook the molecule to a protein big enough to set off the immune
system's alarms.

The drug-plus-protein can be injected directly, to prompt the body to
make its own antibodies. Or scientists can create the antibodies by
working with laboratory animals and inject them into patients.

Either way, the antibody grabs the drug in the bloodstream, before it
gets to the brain.

At least, that's how it works in animals so far.

Antibodies could be used to treat an overdose or block a drug's
effects for a longer period, perhaps a month or more.

Both PCP and methamphetamine last for days in the body, unlike
cocaine, which is metabolized in 20 minutes or so.

PCP intoxication can be fatal and both it and amphetamine psychosis
can leave permanent mental scars, said Frank Vocci, head of
medications development for the National Institute on Drug Abuse and
Alcoholism.

The ability to bind the drugs to antibodies could be a major leap
forward in treating them, he said.

Cocaine addiction is a much bigger and trickier problem. More than 2
million people need treatment. About 900,000 a year start treatment,
but at least three-quarters go back to the drug, Vocci said.

"Maybe if we had something to help them out for the initial period, it
might boost the efficacy longer," he said.

Scientists involved in the research discussed their work yesterday at
a meeting of the American Chemical Society in New Orleans.

Already, one cocaine vaccine, developed by a biomedical company in
Massachusetts, is being tried on people at a Connecticut clinic. So
far, only the safety has been tested and it had virtually no side
effects, said Dr. Thomas Kosten, a psychiatry professor at Yale
University and chief of psychiatry for the Veterans Administration in
Connecticut.

The study was not designed to look at the effectiveness of the
vaccine, but a few of the participants reported that cocaine "doesn't
seem to have the bang that it used to have," Kosten said.