June 16th, 2011
FDA: Varenicline (Chantix) May Increase Risk for CV Events
The FDA said that the anti-smoking drug varenicline (Chantix) may increase the risk for cardiovascular events in people who already have cardiovascular disease. The new information will be added to the drug’s label and Medication Guide for patients.
The FDA does not recommend that people with cardiovascular disease stop taking varenicline, but it says that physicians and patients should weigh the known benefits and risks from the drug. Pfizer, the drug’s manufacturer, will be required to conduct a large meta-analysis.
The new action is based on an FDA review of a study of 700 patients with cardiovascular disease who were randomized for 12 weeks to either varenicline or placebo, followed by a 40-week nontreatment period. Varenicline use was associated with significant advantages (over placebo) in the Continuous Quit Rate during weeks 9 through12 (47% vs. 14%; P<0.0001) and in the continuous abstinence rate from weeks 9 through 52 (19% vs. 7%; P<0.0001). However, cardiovascular adverse events were more common in the varenicline arm than in the placebo arm, although the trial was not powered to detect significant differences. Here are the FDA data:
Adjudicated Cardiovascular Events During the 52-Week Study Period (≥1% in any group)
|Varenicline N=353* n (%)||Placebo N=350 n (%)|
|Nonfatal myocardial infarction||7 (2.0)||3 (0.9)|
|Need for coronary revascularization†||8 (2.3)||3 (0.9)|
|Hospitalization for angina pectoris||8 (2.3)||8 (2.3)|
|New diagnosis of peripheral vascular disease (PVD) or admission for a procedure to treat PVD||5 (1.4)||3 (0.9)|
*Three patients in the varenicline arm did not meet the protocol-specified definition of stable cardiovascular disease but were included in the safety analysis population.
†Patients with need for coronary revascularization in the varenicline arm include 5 patients who are also counted under nonfatal myocardial infarction and/or hospitalization for angina pectoris events. Patients with need for coronary revascularization in the placebo arm include 2 patients who are also counted under nonfatal myocardial infarction and/or hospitalization for angina pectoris.