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Aug. 14, 2006 ? The latest weapon in the war against smoking, Chantix, is an effective way for smokers to kick the habit without resorting to taking nicotine in other forms, according to two new studies.
In one of the studies, Chantix was shown to be almost three times as effective as a placebo. It also worked better than Zyban, another drug used by smokers, in the study.
Chantix (varenicline tartrate) was approved by the FDA in May 2006.
It acts at sites in the brain affected by nicotine to do two things: It mimics the effects of nicotine to help stave off cravings and, when used with nicotine, it blocks some of the reinforcing, pleasurable effects of smoking.
However, unlike smoking cessationsmoking cessation tools such as gum and patches, Chantix is not a nictotine replacement.
The approved course of Chantix treatment is 12 weeks, but longer treatment may help some smokers. In addition, counseling is recommended as part of the Chantix treatment program.
"It's a significant new arrow in the quiver," Eric C. Westman, MD, tells WebMD, referring to Chantix.
"It's the first new medication we have had in 10 years and it should create some momentum for people to quit again," says Westman, who is medical director of the Center for Nicotine and Smoking Cessation Research at Duke University School of Medicine, in Durham, N.C.
Studies Show Efficacy of Chantix
The two new studies were published in the Aug.14/28 issue of the Archives of Internal Medicine. They were done by researchers at multiple centers in the U.S.
One study looked at otherwise healthy smokers, aged 18 to 65, who smoked around 20 cigarettes a day for about 24 years. Those who received Chantix with brief behavioral counseling were more likely to kick the habit than smokers who got a placebo.
What's more, smoking-cessation rates improved with higher doses of the drug. Participants who took one milligram (mg) twice daily (the highest dose used in the study) had the best quit rates.
In the study, participants received one of the following treatments:
The Chantix courses were for six weeks, plus an additional week of placebo. The Zyban and placebo courses were for seven weeks.
The four-week continuous quit rates for the various treatments were:
Long-term quit rates at one year were 14% for the group that received 1 milligram twice daily of Chantix, vs. 5% for the placebo, the study showed.
In a related study by the same researchers, 647 smokers were divided into four test groups that received Chantix for 12 weeks, as well as a placebo group. Two of the test groups took 0.5 milligrams Chantix twice a day; the other two received 1 milligram twice a day.
At the end of a year, quit rates were 22% among the smokers who took 1 milligram of Chantix twice a day, 19% for those who took 0.5 milligrams of Chantix twice a day, and 4% in the placebo group.
The main side effect, nausea, was reduced if doses started low and were increased over time.
Time to Quit Is Now
"This is a highly effective treatment for nicotine dependence and it shows superior efficacy compared with ," Bankole A. Johnson, DSc, MD, PhD, tells WebMD. Johnson, a professor of psychiatry and neuroscience at the University of Virginia in Charlottesville, wrote an editorial accompanying the new studies.
"The side effect profile is tolerable and it represents a new way forward because all the other drugs out there are simply trying to replace nicotine," he says.
"Over the last decade there have been new treatments that move away from nicotine replacement, and in the next several years we will likely see a nicotine vaccine, which will be very promising," according to Johnson.
The bottom line is that "there are treatments that are available now that are excellent, [so] don't delay seeking treatment," Johnson says.
Westman adds that "having another medication or pill will definitely be advantageous, but we do not have enough information to know for whom will be better, work in, or not work in."
"I don't know where it will fit," says Westman, "but I think most people will still try nicotine replacement first and then try [this drug]."
Plant-Based Cure Underused?
In related news, a Swiss researcher reports that cytisine, a plant-derived medication used to treat tobacco dependence in Eastern Europe for four decades, may be an effective, but highly underutilized alternative.
Jean-Francois Etter, PhD, MPH, of the Institute of Social and Preventive Medicine at the University of Geneva in Switzerland, cites as a reason the fact that existing studies on the chemical are not published in English.
The substance is found in a plant known as the golden rain tree, or Cytisus laburnum. During World War II, smokers used leaves from this plant as a tobacco substitute.
In fact, Chantix is derived from the same plant.
Cytisine is now marketed for smoking cessationsmoking cessation under the name Tabex by a Bulgarian company.
In a review of 10 studies from Bulgaria, Germany, Poland, and Russia, dating from 1967 to 2005 and involving 4,404 smokers, this plant-based agent was found to be effective in helping people quit smokingquit smoking.
It's a travesty that "an apparently effective treatment for the first avoidable cause of death in developed countries remained largely unnoticed despite research published during the past 40 years," Etter writes in his report, also published in the same issue of the Archives of Internal Medicine.
"How many other effective drugs are there for which efficacy remained unnoticed because existing trials were not published in English in Western countries?" he asks.
SOURCES: Nides, M. Archives of Internal Medicine, Aug. 14/28, 2006; vol 166: pp 1561-1568. Oncken, C. Archives of Internal Medicine, Aug. 14/28, 2006; vol 166: pp 1571-1577. Johnson, B. Archives of Internal Medicine, Aug. 14/28, 2006; vol 166: pp 1547-1559. Etter, J. Archives of Internal Medicine, Aug. 14/28, 2006; vol 166: pp 1553-1559. Eric C. Westman, MD, medical director, Center for Nicotine and Smoking Cessation Research, Duke University School of Medicine, Durham, N.C. Bankole A. Johnson, DSc, MD, PhD, professor of psychiatry and neuroscience, University of Virginia, Charlottesville.