THURSDAY, May 11, 2006 (HealthDay News) -- Smokers looking to quit were given a new tool Thursday when U.S. regulators signed off on a drug that appears to be markedly better than existing treatments.
The drug -- Chantix (varenicline tartrate) -- received a "priority review" by the U.S. Food and Drug Administration, meaning it was approved within six months rather than in the usual 10-month review period, because of its demonstrated effectiveness in clinical trials.
"We did a priority review because at the time the application was filed, a preliminary review of the efficacy indicated that smokers treated with Chantix may have a superior rate of smoking cessation compared to another currently approved smoking cessation product, which was Zyban," said Dr. Curt Rosebraugh, the FDA's deputy director for the Office of Drug Evaluation II and Center for Drug Evaluation and Research.
Unlike Zyban, which is an antidepressant, Chantix acts on areas of the brain affected by nicotine. It may also ease withdrawal symptoms and block the effects of nicotine if people resume smoking, the agency said.
In 12-week clinical trials, 44 percent of patients taking Chantix had quit smoking after four weeks, compared with 30 percent taking Zyban and 17 percent taking a placebo, Rosebraugh said.
"In these studies, they followed people for a year," Rosebraugh added. "In general, 22 percent of smokers who took Chantix, compared to 16 percent for Zyban and 10 percent for placebo, were still smoke-free at the end of a year."
Rosebraugh noted that participants in the trials received intensive counseling and cognitive behavioral therapy in addition to the new drug. "The product is labeled that they [smokers] should have counseling during drug treatments," he said.
If a smoker has quit after 12 weeks of treatment with Chantix, it's recommended that he or she receive an additional 12 weeks of treatment, Rosebraugh said. "This is recommended to further increase the likelihood of long-term smoking abstinence," he said.
Chantix, manufactured by Pfizer Inc., isn't designed to be used with other smoking-cessation products, and is intended for people aged 18 and older, Rosebraugh said. The most common side effects seen in the clinical trials were abnormal dreams and nausea, he said.
Dr. Tony P. George is director of the Program for Research in Smokers with Mental Illness at Yale University, and serves as an advisor to Pfizer on Chantix. The drug "is unique," he said, "because it gives the customer what they want."
"It's like nicotine but it's not nicotine," he said. "What's nice about Chantix is it's a substitute for nicotine without all the harm."
However, George agreed that smoking-cessation counseling is crucial. "Counseling is critical," he said. "If we don't have the counseling, the drugs don't work."
One expert thinks the new drug will only have a small impact on the smoking problem.
"It's a small step in the right direction, but only a very small step," said John F. Banzhaf, executive director of Action on Smoking and Health. "It only improves the one-year success rate by only 4 percent, which is not something to run around and cheer about."
"I am afraid that too many people will take the drug thinking that the drug will get them to quit smoking," Banzhaf added. "Smoking is a two-part problem. The drug only deals with half the problem."
Banzhaf said smoking involves both a physical and psychological addiction. "If people think they can just pop a pill and not modify behavior and not go to behavior-modification programs, the drug is likely not to be effective," he said.
Another expert thinks the drug might work better for some patients than others.
"I have patients who have been waiting for the approval of Chantix," said Dr. Joseph R. DiFranza, a professor of family medicine and community health at the University of Massachusetts Medical School.
"While Zyban has been effective in helping smokers quit, some smokers have not tolerated Zyban because of side effects, or were unable to quit with Zyban," DiFranza said. "Since Chantrix is a different drug that works through a different mechanism, it offers hope to those who were unable to quit with the help of Zyban."
But another expert thinks Chantix will benefit people trying to quit smoking.
"Medication alone is rarely sufficient to achieve behavior change, but it can be an important and even necessary part of a successful program," said Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine. "I will be pleased to offer Chantix as an option to my patients who smoke and want to quit."
An estimated 44.5 million adults in the United States smoke cigarettes and more than 8.6 million of them have at least one serious illness caused by smoking, according to the U.S. Centers for Disease Control and Prevention.
More information
The National Institutes of Health can tell you more about quitting smoking.
