Chantix Risks Do Not Include Heart Attacks, Heart Problems: Report

A new review of prior clinical trial data suggests that side effects of Chantix do not appear to increase the risk of heart attacks or other heart problems, contradicting the findings of a study published last year involving the popular stop-smoking drug.

In a study published in the current issue of the British Medical Journal (BMJ), researchers from University of California San Francisco (UCSF) examined the heart risks of Chantix after questions emerged about a study published in the Canadian Medical Association Journal in July 2001.

In that prior study, researchers indicated that there was a significantly increased risk of heart attacks, strokes and other cardiovascular events with Chantix. However, UCSF researchers questioned the way that prior study was conducted.

Although Chantix only remains in the body for up to seven days after the medication is last used, the prior research included data on subjects throughout the entire trial period, which in many cases was as long as a year. UCSF researchers only followed subjects during their treatment window or within 30 days after last use, suggesting that the longer heavy smokers are followed, the more likely an unrelated cardiovascular event is to occur.

The new study examined data from 22 different clinical trials involving more than 9,200 people and found that the difference in heart risks with Chantix was only about 0.27% higher when use of the drug was compared to a placebo, which is not a clinically or statistically significant increase.

Chantix (varenicline) was approved in the United States by the FDA in 2006 as a prescription medication to help people quit smoking. The drug works by reducing the positive feelings that come from cigarettes, blocking the receptors in the brain commonly stimulated by nicotine.

Since the drug was introduced, serious concerns have emerged about potential Chantix risks, which have impacted sales of the medication. However, most of the concerns have involved the psychological side effects of the medication, which have been found to increase the risk of sudden, unusually aggressive behavior, thoughts of self-harm and suicide.

In June 2009, the FDA added a “black box” warning about the risk of psychological problems with Chantix, and Pfizer was ordered to conduct additional clinical trials to provide more data on how often neuropsychiatric symptoms and suicide with Chantix occur and what conditions cause them. The new study does not address these Chantix risks.

A number of family members of former users are now pursuing a Chantix lawsuit against Pfizer, alleging that death or other injuries from a suicide attempt may have been prevented if the drug maker had properly warned about the psychological risks.