Pfizer said on Thursday it is pausing distribution of its anti-smoking treatment, Chantix, after finding elevated levels of cancer-causing agents called nitrosamines in the pills.
The drugmaker is recalling a number of lots of the anti-smoking drug.
Pfizer said the impacted lots of Chantix contained levels of nitrosamines, but insisted there is ‘no immediate risk to patients taking this medication’ and the recall is out of an abundance of caution.
The Food and Drug Administration shared the company’s press release on its website, noting that the company is not being mandated by the federal agency to carry out the recall.
The U.S. drug regulator has in the past reached out to companies whose drugs had N-nitrosodimethylamine (NDMA) over accepted levels.
Chantix was approved by the FDA in May 2006 as a prescription medication which helps adults aged 18 and over quit smoking and is used for 12 to 24 weeks.
The impacted lots contain levels of carcinogenic chemicals, called nitrosamines, that are above the company’s own acceptable daily intake level
Pfizer said in its release: ‘The health benefits of stopping smoking outweigh the theoretical potential cancer risk from the nitrosamine impurity in varenicline’.
The firm added that people who smoke cigarettes are 15 to 30 times more likely to get lung cancer than people who do not smoke.
Nitrosamines are naturally-occurring organic compounds found in a variety of foods, including meat, dairy and vegetables, according to the FDA. Everyone is exposed to the chemicals at some level.
However, if ingested in high amounts over long periods of time, nitrosamines could increase someone’s risk of developing cancer.
The FDA began asking pharmaceutical companies to test their drugs for nitrosamines after high amounts were found in several different kinds of blood pressure medications three years ago.
Last year, the FDA found high levels of nitrosamines in the popular diabetes drug, metformin, Bloomberg reported. In 2019, Sanofi SA recalled its heartburn drug Zantac for having high amounts of the carcinogenic ingredient.
Pfizer didn’t indicate how the nitrosamines got in Chantix. The source of the chemicals in medication could come from its manufacturing process, its chemical structure or even the conditions under which they are stored and packaged.
Pfizer first announced that it was planning a recall of the drug on June 24 after discovering the likely carcinogen. Then, on July 2, it listed a recall on nine lots of the drug that were impacted and sitting in warehouses.
The July 16 recall, however, includes 12 more lots of the drug, which were already distributed to wholesalers in the U.S. and Puerto Rico between June 2019 and June 2021.
The company released a list of the lot numbers and urged consumers to check if their prescription is affected. They include 00019213, EC6994, EA6080, EC9843, 00020231, 00020232, 00020357, 00020358, 00020716, ET1600, ET1607 and ET1609.
The FDA approved Chantix in 2006 as a prescription medication for adults, 18 and older, to use for 12 to 24 weeks to help quit smoking
‘Patients currently taking Chantix should consult with their doctor to confirm if they received an affected lot, and if appropriate, about alternative treatment options,’ the company said, adding, ‘To date, Pfizer has not received any reports of adverse events that have been related to this recall’.’
Chantix sales dropped 17percent in 2020, from $1.1billionm to $919 million, after the company lost protection on one of its main patents in the United States in November, according to Bloomberg.
While ‘generic competition for Chantix has not yet begun, it could commence at any time,’ Pfizer said in its quarterly report in May.