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Posted on Apr 04, 2005, 8 a.m.
By Bill Freeman
According to Jonathan Brodie, M.D., of New York University School of Medicine, there is no effective treatment for the several million cocaine abusers in the United States that has been approved for use. Dr. Brodie says the total social cost of overall drug addiction is as much as 1 trillion dollars a year in the United States.
THE STUDY: Brodie and colleagues ran studies on the drug Gamma Vinyl Gaba (GVG) in Mexico, as it is not approved for use in the United States. It goes by the name Sabril in Europe, where it is widely used for treating pediatric epilepsy. Upon study, researchers found the drug could end cravings for people who are dependent on cocaine and methamphetamine. Drug users could stop using under conditions where their health was not impaired or jeopardized. Of the 20 participants who enrolled in the study, eight of them stayed clean for about seven weeks. Six months later, six of the eight patients were still clean. Many years of animal studies led up to this research. Dr. Brodie says those results show GVG works against other drugs as well, such as inhalants, heroine, nicotine, and alcohol.
SIDE EFFECTS: In 1998, GVG was close to approval for use in the United States, but then reports surfaced of people having vision problems from using the drug. Dr. Brodie and researchers then did a safety trial in drug-using patients. Thirty subjects participated in the nine-week trial. Their eyes were measured before, during, and after the trial, and no physical changes were observed. Dr. Brodie says what was observed, however, was that, "16 of those 30 people who enrolled and finished the trial stopped using their drugs. They stopped using for a month straight. In fact, for many of them, the mean was about six weeks. And these were people who used [certain drugs] daily." Dr. Brodie says vision problems from GVG must be related to the total exposure of the drug -- people taking the drug over a period of years in large quantities. A significant percentage of these people will, according to Dr. Brodie, develop what's called a visual field abnormality. This is similar to someone who wears glasses and has blurred vision outside the field of the glasses. But Dr. Brodie says the amount of the drug that appears to be adequate to stop addiction is a small fraction of the amount that would be necessary to produce side effects such as vision problems.
HOW IT WORKS: The drug seems to block the rapid rise in a brain chemical called dopamine, which is associated with drug abuse. GVG also seems to block cravings, so that the two related aspects of addiction -- the craving and the reward -- are both blocked by GVG.
CLINICAL TRIALS: In January 2005, GVG was given the go-ahead for use in clinical trials in the United States.
