Chantix May Increase Risk of Heart Problems, FDA Warns

Federal drug regulators indicate that data from a number of different clinical trials suggest that there are signs that side effects of Chantix may indeed cause an increased risk of heart attacks, strokes and other cardiovascular problems. 

The FDA issued a drug safety communication on December 12, updating its ongoing safety review of Pfizer’s smoking cessation medication Chantix.

According to FDA investigators, a meta-analysis of clinical trials involving the drug found an increased incidence of heart problems and heart problem-related deaths among Chantix users, when compared to individuals who received a placebo. The FDA ordered the drug maker to perform the analysis of the potential Chantix heart risks following a prior drug safety communication issued in June 2011.

“A higher occurrence of major adverse cardiovascular events (a combined outcome of cardiovascular-related death, nonfatal heart attack, and nonfatal stroke) was observed in patients using Chantix compared to placebo,” the FDA warns. However, the agency said that the meta-analysis numbers did not reach the level of statistical significance, suggesting that the results may be due to chance.

However, the FDA noted that “the data were analyzed many different ways and consistently showed a higher occurrence of events in patients using Chantix, which makes it seem more likely that it is related to the drug and not purely a chance finding.”

Chantix Heart Problems Debated Among Researchers

The revelation by the FDA addresses questions about the risk of heart problems from Chantix, which have been debated since the FDA first issued a warning and a June 2011 study published in the Canadian Medical Association Journal seemed to confirm the heart concerns with Chantix. However, in May 2012, a study published in the British Medical Journal raised doubts about the Canadian study’s findings.

The FDA is advising patients taking Chantix to contact their doctor if they experience:

• Trouble breathing or shortness of breath
• New or worsening chest pain
• New or worsening leg pain while walking
• Sudden weakness, paralysis, or numbness
• Difficulty understanding speech or speaking

Chantix Side Effects Also Include Psychological Problems

Chantix (varenicline) was approved in the United States 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.

Within months after the medication was introduced, reports began to surface about individuals committing suicide or engaging in other unusual behavior, which was allegedly caused by the neuropsychological effects of the medication on the brain.

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 FDA’s announcement does not address these Chantix risks.

Pfizer faces an estimated 2,500 Chantix lawsuits filed on behalf of users who committed suicide or suffered severe injuries that were allegedly caused by the psychological side effects of the stop-smoking drug. All complaints filed in U.S. District Courts throughout the United States are consolidated for pretrial proceedings before Judge Inge Johnson in the Northern District of Alabama.