More Chantix Recalled Due To Cancer-Causing Chemicals, As N-Nitroso Varenicline Found in Additional Lots

Another four lots of the smoking cessation drug Chantix have been recalled due to the presence of a toxic byproduct, which could cause users to develop cancer while taking the drug to avoid the health risks associated with smoking.

The FDA announced a Chantix recall expansion on August 16, after more batches of Pfizer’s drug tested positive for N-nitroso-varenicline at levels above the drug maker’s established Acceptable Daily Intake (ADI) threshold.

The expansion follows a Chantix recall announced on July 19 for the same problem, and the drug’s removal from the market.

Chantix (varenicline) is a prescription medication introduced by Pfizer in 2006, designed to help people quit smoking. However, less than three years after its release, the FDA required Pfizer to add a “black box” warning, following a number of reports involving suicide and other unusual behavior among users. The FDA later rescinded the label requirement, and removed the warning in December 2016.

The manufacturer announced it was halting Chantix distribution in June, when the drug became the latest linked to a class of cancer-causing chemicals known as nitrosamines. It announced a recall in Canada at the time, but did not issue a U.S. recall until a month later.

Over the last few years, several drugs, such as Zantac, valsartan and metformin, have faced similar recalls, primarily to do the presence of a nitrosamine known as N-Nitrosodimethylamine (NDMA).

Pfizer indicates it has received no reports of adverse events linked to this recall, and the FDA is not calling on users to stop taking the drug.

The latest recall expansion affects four additional lots of Chantix 0.5 mg tablets, 1 mg tablets and 0.5/1 mg tablets. Sold in 56 tablet bottles, cartons with blister packs of 0.5 mg tablets and 1 mg tablets. A complete list of recalled products is available on in the recall notice linked above. The products were distributed in the U.S. and Puerto Rico from June 2019 to June 2021.

Pfizer has instructed wholesalers and distributors to stop use and distribution of these products and quarantine them immediately. They, and patients, have been instructed to contact Stericycle at 888-276-6166 for information on how to return the product and obtain a reimbursement.

Those who received free Chantix through the Pfizer Patient Assistance Program (PAP) or the Pfizer Institutional Patient Assistance Program (IPAP) have been instructed to request replacement product by calling 833-203-2776.