FDA Takes Steps to Maintain Supply of Smoking Cessation Therapy

N-nitroso-varenicline may be associated with an increased cancer risk based on data from closely related nitrosamine compounds.

The Food and Drug Administration will permit varenicline tablets containing N-nitroso-varenicline up to the interim acceptable intake limit of 185ng per day to be distributed in the US in order to maintain an adequate supply of the smoking cessation therapy in the country.

According to the Agency, exposure to N-nitroso-varenicline below 185ng per day was determined to present minimal additional cancer risk when compared with a lifetime exposure at 37ng per day, the FDA’s acceptable intake limit. In an updated statement, the FDA reiterated that the health benefits of smoking cessation continue to outweigh the cancer risks from the nitrosamine impurity.

To mitigate a potential shortage, temporary distribution of Apo-Varenicline, a varenicline product distributed by Apotex Inc. in Canada, will be allowed in the US.


FDA will not object to distribution of Chantix (varenicline) with nitrosamine below the interim acceptable intake limit. News release. Accessed July 19, 2021. https://www.fda.gov/drugs/drug-safety-and-availability/fda-updates-and-press-announcements-nitrosamine-varenicline-chantix.

This article originally appeared on MPR