U.S. RESEARCHERS TAKE AIM AT ADDICTION

Medications Tested To Try To Defeat Habit

New York -- Taking a bold approach to addiction, researchers at Columbia
University are offering free heroin to addicts and paying them to use it
under a federally authorized program aimed at finding a cure for their drug
habits.

Since September, 14 addicts have received regular doses of pure heroin
after being given naltrexone, buprenorphine or methadone, which are
medications found to be effective in neutralizing heroin's high.

The researchers want to learn whether stronger doses of these medications
are needed and can be prescribed without risk, particularly in light of the
increasingly pure heroin being sold on the streets.

"A dose that was probably good enough 15 years ago may not be good enough
for heroin now," said Dr. Herbert Kleber, a professor of psychiatry at
Columbia who directs the medical college's division on substance abuse and
is medical director of the National Center on Addiction and Substance Abuse
at Columbia.

Heroin and cocaine have been tested on mice and other laboratory animals.
But Columbia's study is now the only one in the country testing addicts
with heroin.

Dr. Marian Fischman, a psychologist at Columbia who studies medications for
drug abusers, said the volunteers, who agree to stay in the hospital for
six or seven weeks, had rejected offers to treat their heroin habit.

"We would not give a drug of abuse to someone who was seeking treatment,"
she said. "We refer anyone to treatment who would even moderately consider
it."

The medications being tested affect the brain in different ways. Naltrexone
is an antagonist, meaning that it blocks the effect of heroin on the
brain's receptors. Methadone is an agonist, which stifles the craving for
heroin by binding to the brain receptor. The third, buprenorphine, acts as
an agonist at lower doses and as an antagonist at higher doses.

Six related drug-addiction studies are being conducted at Columbia's
College of Physicians and Surgeons, all of which focus on the role existing
medications can play in defeating drug addictions.