Chantix Problems Not Properly Submitted to FDA: Report

Pfizer failed to properly send hundreds of adverse event reports involving psychiatric problems with Chantix to the FDA for years, leading to an underestimation of the impact of Chantix side effects. 

The Institute for Safe Medicine Practices (ISMP) released their quarterly report (PDF) this week on adverse event reports submitted to the FDA. In the report, the nonprofit indicated that the number of Chantix problems were largely underestimated in prior adverse event reporting.

Pfizer failed to properly report hundreds of serious psychiatric problems associated with Chantix since 2006, according to ISMP. Included among the unreported problems were 150 suicides on Chantix that date back to 2007.

The ISMP is calling for an FDA investigation into Pfizer’s actions. 

The number of Chantix problems reported to the FDA once again out numbers any other drug monitored by the group, including more than twice as many deaths from Chantix than were reported with any other medication. The ISMP indicates that Chantix was associated with more suicides, more reports of depression, psychological side effects and violence than any other prescription drug.

In the third quarter of 2010, the ISMP noticed a spike of 1,055 serious adverse events reported for Chantix. The non-profit organization analyzed the spike in reports and found 589 reports of serious Chantix side effects and deaths that occurred years ago but had not been reported into the FDA’s Adverse Events Reporting System (AERS) until July 2010. The ISMP found 589 reports from 2009 and early 2010, 176 reports from 2008, 119 reports from 2007 and 12 reports from 2006; the year Chantix was approved.

Federal drug regulations require companies to file serious adverse event reports within 15 days of receiving them. Last year, the FDA sent a warning letter to Pfizer saying that it had found discrepancies in its compliance with adverse event reporting rules since 2004. The FDA said the company had failed to submit serious reports, misclassified other reports and downgraded serious problems and filed them with non-serious reports.

Among the newly discovered adverse events were 150 Chantix suicide reports, which more than doubled the number of suicides linked to the drug. Previously, the FDA was aware of 122 reports of suicide submitted by Pfizer, health care professionals and consumers. It is generally believed that adverse event reports received by the FDA only constitute a small portion of the total number of occurrences, but drug makers are relied on to promptly report any problems they are aware of.

A black box warning was added in 2009 about the risk of suicide and psychological side effects from Chantix. In addition, a number of Chantix lawsuits have been filed throughout the United States on behalf of individuals who have experienced an injury or died.

ISMP indicates that it asked Pfizer why the reports were not submitted before July 2010, but the company refused to answer, saying the organization could soon be involved in the Chantix litigation.

The FDA told the ISMP that the reports had been erroneously included in about 26,000 non-serious adverse events, and the FDA did not discover the problem until last July. However, no explanation was given for why Pfizer classified such serious events as suicides among non-serious reports. Instead, the drug maker filed them as “expected adverse events.”

Chantix (varenicline) was approved in the United States by the FDA in 2006, and works by reducing the positive feelings that come from cigarettes, blocking the receptors in the brain commonly stimulated by nicotine. However, the medication has been associated with an increased risk of neuropsychiatric injuries leading to behavioral changes, depression, aggression, agitation, hostility, rage, suicidal ideation, suicide attempts and, in many cases, successful suicide.