Smokers with a particular genetic variation in a key enzyme are more likely to succeed in their quit attempts if they get bupropion therapy as well as counseling, according to researchers.

Science Daily reported Sept. 23 that researcher Anna Lee and colleagues performed CYP2B6 genotyping on smokers, who then either got bupropion treatment for nicotine addiction or a placebo for 10 weeks. They found that those with the CYP2B6*6 allele of the gene had a 32.5-percent abstinence rate on bupropion, compared to 14.3 percent for the placebo group. That contrasted with those found to have the CYP2B6*1 allele, who did well regardless of whether they were on bupropion or the placebo.

"We look forward to the era of personalized medicine, when doctors are able to use genetic information about their patients to guide treatment," noted John H. Krystal, M.D., editor of the journal Biological Psychiatry. "We are not ready to use this information in clinical practice, but this study provides us with a good example of the type of information that might, some day, guide the treatment for smoking."

The study was published in the Sept. 15 issue of Biological Psychiatry.