Published on November 18, 2004 at 6:30 PM
Of the 30 volunteers, 18 stayed in the study for the nine-week duration. Of those, 16 were methamphetamine- and cocaine-free for more than four consecutive weeks while two continued using but in reduced amounts. Twelve of the 16 remained free of methamphetamine and cocaine through the end of the study. No subject, whether they completed the trial or not, developed defects in visual fields or acuity.
"Due to the open-label nature of this study and the lack of a control group, we cannot conclude that these subjects' ability to abstain from drug use was a direct result of being given GVG," said Dr. Dewey. "However, in a group of heavy users where none had stayed 'clean' for more than several consecutive days in the past year, it is remarkable that 16 of 30 avoided using these highly addictive drugs for approximately four consecutive weeks while on GVG," said Dr. Dewey.
"Of course, the conclusive demonstration of treatment efficacy can only be provided by an appropriately blinded randomized study, where some patients are given GVG and others a placebo, and neither the researchers nor the subjects know which is which until after the results are analyzed," noted Dr. Brodie.
With the lack of visual side effects observed for the doses used in this study - a factor that has been viewed as an impediment to getting GVG approved in the United States - the scientists hope to see a large-scale study conducted soon.