A genetic variant present in nearly half of Americans of European ancestry is linked to greater effectiveness of the smoking cessation medication bupropion (Zyban), according to research by scientists supported by the National Institute on Drug Abuse (NIDA) and the National Cancer Institute (NCI), part of the National Institutes of Health (NIH). People with this variant were less likely than those without it to have resumed smoking six months after treatment with bupropion.
The study, published in the September issue of the journal Biological Psychiatry, is a step toward the goal of being able to tailor smoking cessation treatment to individuals based on their unique genetic make-up.
"This study is part of our ongoing commitment to develop more accurate and personalized approaches to medicine," said NIH Director Dr. Elias A. Zerhouni. "This kind of genetic research is helping us to better understand why some people respond to certain smoking cessation treatments, and others don't."
The study involved more than 300 smokers who had been randomly assigned to treatment with either bupropion or a placebo (sugar pill) for 10 weeks. Participants were genetically tested for the presence of a variant form of the CYP2B6 gene. The study was co-led by Dr. Rachel F. Tyndale of the Center for Addiction and Mental Health at the University of Toronto, Canada, and Dr. Caryn Lerman of the Transdisciplinary Tobacco Use Research Center at the University of Pennsylvania (TTURC) in Philadelphia.