FDA Continues to Monitor Chantix Safety
Chantix (varenicline) was granted approval by the Food and Drug Administration (FDA) for use as a smoking cessation drug in May 2006. Thru postmarketing surveillance, the FDA soon became aware of the potential for serious neuropsychiatric events and continues to monitor Chantix safety.
Chantix acts at sites in the brain affected by nicotine. This may help those who wish to stop smoking by providing some nicotine effects to ease the withdrawal symptoms and by blocking the effects of nicotine from cigarettes if users resume smoking.
The early adverse event reports (AERs) suggested an association between Chantix and serious neuropsychiatric symptoms – suicidal thoughts and aggressive behavior. In July 2009, these AERs lead the FDA to required that Pfizer update the Chantix label with a black box warning describing the risk for neuropsychiatric events.
In July 2010, after Pfizer resubmitted a large number of adverse event reports, at the request of FDA, the Agency review confirmed what they already knew about Chantix. The FDA notes these reports would not have changed the Agency's position on the drug's risks and benefits, given that the data in these reports were consistent with those that led to the 2009 labeling change.
At this point, based on the data, FDA does not have any new safety concerns with Chantix, though those that have been established remain under active review.
The Agency continues to monitor Chantix for serious and unexpected events. The FDA has initiated two observational safety studies on Chantix, one with the Veterans Administration and one with the Department of Defense.
The FDA clarified the instructions for reporting AERs last year when the Agency became aware that a few manufacturers were submitting adverse events reports to FDA through improper channels. These instructions are available on the FDA website for AERS Electronic Submissions.
FDA will continue to monitor the postmarket safety of Chantix and will communicate any new information as it becomes available. A list of previous safety communications can be found on the Chantix Information page.
Smoking remains the leading cause of preventable disease, disability, and death in the United States. I would encourage you to stop smoking. If you and your doctor make the choice to use smoking cessation medications to aid you in stopping, then watch for any unusual changes in mood or behavior after starting these drugs.