Pfizer expands Chantix recall due to potential impurity-linked cancer risk
Pfizer has voluntarily expanded its recall of Chantix 0.5 mg and 1 mg tablets because of the presence of the nitrosamine N-nitroso-varenicline at or above the FDA interim acceptable intake limit.
According to a Pfizer press release, long-term ingestion of this nitrosamine may be linked to a theoretical potential increased risk for cancer among humans; however, patients taking Chantix (varenicline, Pfizer) are not at immediate risk. Further, the release noted that the health benefits of smoking cessation are greater than the possible risk from the impurity.
The FDA announced it will not object to certain manufacturers distributing varenicline tablets that contain amounts of the nitrosamine above the administration’s acceptable intake limit of 37 ng per day but below the interim acceptable intake limit of 185 ng per day until the impurity can be removed or lowered to acceptable levels, with the goal of mitigating the effects of a drug shortage due to this ongoing recall. The FDA has allowed for temporary “regulatory flexibility and discretion” regarding Apotex’s distribution of Health Canada-approved Apo-Varenicline tablets in the U.S. These tablets fall within the interim acceptable intake limit.
According to the FDA, patients taking recalled varenicline should continue taking their current medication until they receive a pharmacist-provided replacement or until their doctor prescribes them a different treatment, with the administration echoing Pfizer’s statement related to the health benefits of smoking cessation outweighing those from the varenicline impurity’s cancer risk.
References:
- FDA. FDA updates and press announcements on nitrosamine in varenicline (Chantix). Available at: https://www.fda.gov/drugs/drug-safety-and-availability/fda-updates-and-press-announcements-nitrosamine-varenicline-chantix?utm_medium=email&utm_source=govdelivery. Accessed Sept. 17, 2021.
- FDA. Pfizer expands voluntary nationwide recall to include all lots of Chantix (varenicline) tablets due to n-nitroso varenicline content. Available at: https://www.fda.gov/safety/recalls-market-withdrawals-safety-alerts/pfizer-expands-voluntary-nationwide-recall-include-all-lots-chantixr-varenicline-tablets-due-n. Accessed Sept. 17, 2021.