A novel, experimental drug worked better than existing ones to help people kick the cigarette habit, but not as much as some experts had hoped, the first extensive studies of the drug revealed.
Several studies conducted in Europe on about 2,000 smokers and presented Tuesday at an American Heart Association conference showed that a year after initial treatment with Pfizer Inc.'s varenicline, abstinence rates were 22 percent vs. 16 percent of those given the smoking cessation drug Zyban and 8 percent of those given a fake drug.
The main side effect was nausea but most rated this as mild, said Dr. Serena Tonstad, a preventive cardiology specialist at the University of Oslo, Norway, who led the company-funded study. Fewer than 3 percent of participants stopped the drug because of nausea.
Varenicline works in a completely different way than the nicotine patches, gums and other drugs currently available for smoking cessation.
Tonstad called the results proof of the effectiveness of this approach, but others were not as enthused.
"They may be very pleased with these results but I was less impressed than I'd hoped to be," said Dr. Timothy Gardner, a Delaware cardiologist who led the heart association program committee. "I'm not sure 22 percent at one year would be as good as we would hope for drug therapy."
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