NEW YORK — Pfizer defended a drug used for smoking cessation Monday following reports of a Canadian study that found it raised the risk of heart problems.
The 8,216-patient study of Chantix (varenicline), published in the Canadian Medical Association Journal, found that of the 4,908 patients who received Chantix, 52 had an increased risk of serious heart problems, with similar risks appearing in 27-of-the-3,308 patients who took placebo.