Pfizer Expands Chantix Recall Due to Potential Cancer Risks

Pfizer, the drug manufacturing giant, has recently expanded its prior recall of its popular anti-smoking medication, Chantix. The expanded recall is contemporaneous to the U.S. Food and Drug Administration’s (FDA) recent test results. The FDA discovered high levels of nitrosamines in the drug that were above Pfizer’s established acceptable daily intake levels. High levels of the chemical could potentially pose a cancer risk. Because nitrosamines are the main ingredients in Chantix, Pfizer may face product liability litigation in the near future.

The Recall

Chantix is a smoking cessation treatment used to aid patients in quitting smoking. It has been on the market for 15 years with nearly $1 billion in annual sales. Doctors have prescribed the medication to over 10 million patients. The popularity of Chantix is correlated with a national decline in cigarette smoking. The corresponding associations smoking has with lung cancer and other diseases also played a role in the treatment’s popularity. Chantix (also known as its generic name, varenicline) works by providing nicotine-like effects to lessen the symptoms of nicotine withdrawal. At the same time, Chantix blocks the effects of actual nicotine if the patient attempts to smoke.

Back in June, Pfizer issued a voluntary recall for a total of 12 lots of Chantix products. The recall included two lots of 0.5 milligram tablets and two lots of 1 milligram tablets. Additionally, the recall encompassed eight lots of a kit of 0.5 and 1 milligram tablets. In mid-August, Pfizer subsequently included an additional four lots of products to its recall list. The company distributed the lots to United States wholesalers from June 2019 to June 2021.

Potential Cancer Risk

Pfizer recalled the lots due to the heightened presence of N-nitroso-varenicline, a type of nitrosamine, which is a known carcinogen. The recall warned that long-term ingestion of N-nitroso-varenicline “may be associated with a theoretical potential increased cancer risk in humans.” However, the recall also noted that “there is no immediate risk to patients taking this medication.” The “health benefits of stopping smoking outweigh the theoretical potential cancer risk from the nitrosamine impurity in varenicline.” The recall explained that nitrosamines are common in water and certain foods, such as cured and grilled meats, dairy, and vegetables. Yet, impurities may increase the risk of cancer over “long periods of time.” Nonetheless, “Pfizer believes the benefit/risk profile…remains positive.” The company has not received any reports of adverse events associated with the recall.

The FDA advised wholesalers and distributors to stop distribution and quarantine the product immediately. Moreover, the FDA advised patients to consult their doctor to confirm whether they received an affected lot. If doctors did prescribe an affected lot, the administration encouraged patients to discuss alternative treatment options.

The FDA’s Testing

The recall concedes the present level of N-nitroso-varenicline exceeded the acceptable daily intake. However, Pfizer did not specify the exact amount found in its products. Subsequent FDA testing, however, provides some insight into the carcinogenic effects of the drug. The FDA’s testing of Chantix (and other varenicline products) is ongoing. Nonetheless, the administration has made public its laboratory results indicating the N-nitroso-varenicline levels in Chantix and other varenicline products. As the FDA’s statement explains, the administration considered an acceptable daily intake limit of 37 nanograms per day of N-nitroso-varenicline “reasonably safe for humans.” Exposure above this limit over a long period of time may increase one’s risk of developing cancer. However, the FDA has found that daily intake at or below 37 nanograms, even over the course of 70 years, is not expected to have an increased risk of cancer.

The FDA’s scientists evaluated different N-nitroso-varenicline levels up to 185 nanograms per day. They determined that those levels present minimal additional cancer risk in comparison to exposure rates of 37 nanograms per day. Per the FDA’s chart, the Chantix lots were found to have 150 to 470 nanograms per one milligram tablet.

Litigation to Come?

Pfizer’s recalls are relatively new, and there are no reported adverse events. Therefore, it is still too soon to tell whether the company will face product liability lawsuits over Chantix’s N-nitroso-varenicline levels. FDA investigations are still ongoing. Current testing indicated increased intake levels beyond the daily recommendation over a long period of time may only “minimally” increase one’s risk of developing cancer. So, it is unclear if and when consumers will develop cognizable injuries to form the basis of a lawsuit. Chantix’s recommended “short-term use” of three to six months may help consumers avoid the long-term effects of prolonged N-nitroso-varenicline exposure.

However, Chantix’s recalled lots still have much unknown about it, as the FDA continues testing. The FDA has not mandatorily recalled Chantix in the United States. However, it is worth noting that Canadian authorities have recalled its Chantix (under the name Champix) products in their country.

If consumers file suits over this recall, it won’t be the first time that Chantix faces product danger allegations. Back in 2013, Pfizer paid $273 million to settle the majority of 2,700 state and federal lawsuits. The suits alleged the drug caused psychiatric disturbances, some of which resulted in suicide. In response, the FDA required Chantix to provide a “black box” warning on its labeling. The intent of this was to warn patients and physicians of the drug’s psychiatric effects.