Pubdate: Wed, 25 Aug 1999 Source: Reuters Copyright: 1999 Reuters Limited. Author: Theresa Tamkins EXPERIMENTAL DRUG MAY HELP PCP ADDICTS NEW YORK, Aug 25 (Reuters Health) -- A monoclonal antibody that blocks the effect of PCP, or phencyclidine, may one day be useful as a treatment for recovering addicts, according to results of a new study in rats. PCP, also known as "angel dust," causes hallucinations and psychotic and violent behavior. A 1997 survey conducted by the National Institute of Drug Abuse suggested that 2% of US high school seniors had used the drug in the previous 30 days. The monoclonal antibody, an immune system molecule that is produced in mice and binds to PCP, appears to reduce the effects of the drug when given to animals, according to a report presented Monday at the American Chemical Society meeting in New Orleans. A single injection of the antibody appeared to blunt the effect of the drug for up to 2 weeks, said lead study author Dr. S. Michael Owens in an interview with Reuters Health. "In terms of humans, that would be equivalent to a month or two after administration," said Owens, a professor of pharmacology and toxicology at the University of Arkansas for Medical Sciences in Little Rock. "It's very long lasting," Owens said. The antibody, by binding to PCP, "acts like a sponge in the bloodstream" to keep the drug from going into the brain, he said. More research is needed before it is clear whether or not such an antibody would be safe and effective in humans. Antibodies developed in mice may be recognized and destroyed by the human immune system as foreign, although such molecules can be "humanized" or mouse protein replaced by human protein to help prevent the destruction of the antibody. "We envision this as the first step in eventual human use," Owens said. An injection of the antibody might help blunt the effect of the drug while a person is struggling to overcome addiction, however, it is not a "cure," he said. "We would never envision this as something that cures drug abuse. It would have to be used in conjunction with a treatment plan," he said. "They would enter a treatment program, they would be in counseling, but if there was something in their life that makes them go back to the drug, they wouldn't get any effect." "We don't think this medication would work unless they want to cure themselves," Owens said. - --- MAP posted-by: Jo-D