Pfizer has announced the recall of anti-smoking treatment Chantix due to the presence of unacceptably high levels of N-nitroso-varenicline, a substance whose long-term use has been linked to a higher risk of cancer.
The drugmaker said on September 16 that it is voluntarily recalling all 0.5 mg and 1 mg Chantix tablets distributed in the United States, the US Virgin Islands and Puerto Rico from May 2019 to September 2021.
Nitrosamine N-Nitroso-varenicline was found in tablets at or above levels deemed acceptable by the Food and Drug Administration (FDA).
Pfizer said long-term ingestion of the substance “may be associated with a theoretical potential for increased cancer risk in humans, but there is no immediate risk to patients taking this drug.”
“The health benefits of stopping smoking outweigh the theoretical potential cancer risk from the nitrosamine impurity in varenicline,” Pfizer said, adding that they believe the safety profile of Chantix remains positive and the adverse effects associated with its use. There have been no reports of incidents. .
To reduce the impact of the recall on patients who rely on the drug to help them quit smoking, the FDA said in a follow-up notice Friday that it would allow the distribution of tablets containing N-nitroso-varenicline above the allowable intake. . 37. limit of [nanograms] per day but less than 185 ng per day “unless the impurity can be eliminated or reduced to an acceptable level.” A nanogram is one billionth of a gram.
Echoing Pfizer’s position that the health benefits of quitting smoking outweigh the risks of cancer from varenicline ingestion, the FDA said patients should continue taking their current varenicline medication until their doctor prescribes an alternative treatment. Or a pharmacist provides a replacement.
Pfizer’s Chantix saga began in July when the company recalled nine lots after finding that they may contain nitrosamines above the FDA’s allowable intake levels. At the time, the FDA likewise took a flexible stance to allow the product to be distributed tentatively.
The company later expanded its recall twice to include a total of 16 lots, while the FDA said it was conducting laboratory analysis to check for impurity.
“The agency’s scientists evaluated the risk of exposure to N-nitroso-varenicline at an interim acceptable intake level of up to 185 ng (92.5 ppm) per day and determined that this minimal additional cancer risk compared to the lifetime of exposure to N-nitroso.” Presents- Varenicline at 37 ng per day (18.5 ppm) level,” the FDA said.
On August 11, the FDA approved a clinically equivalent varenicline product manufactured by Par Pharmaceutical.
This News Originally From – The Epoch Times