Pfizer Suspends Global Distribution of Chantix Smoking-Cessation Pill on Contamination Concerns

As a precaution, Pfizer suspended distribution while determining the extent of the contamination, the spokesman said.

The company said it was testing lots for the presence of nitrosamines at the request of the U.S. Food and Drug Administration and other regulators. It didn’t specify the number of lots affected or where they were found.

Pfizer, of New York City, said the drug’s benefits outweigh the potential risks, if any, posed by nitrosamine exposure from Chantix.

Canadian health regulators posted online a recall notice for the drug, which is called Champix outside the U.S. Chantix isn’t currently on the FDA’s online list of recalled products. The FDA didn’t immediately respond to a request for comment.

“We have worked hand-in-hand with regulatory authorities around the world,” Pfizer said.

The health news website STAT earlier reported the distribution suspension and recall.

Nitrosamines are common in water and foods, including cured and grilled meats, dairy products and vegetables, and aren’t thought to cause harm if ingested at low levels, according to the FDA’s website.

The chemical may increase the risk of cancer, however, if people are exposed to high levels and over long periods, according to the FDA.

Someone taking a drug that contains the impurities at or below the acceptable daily amount each day for 70 years isn’t expected to have an increased risk of cancer, the FDA website said.

The FDA has been investigating the presence of nitrosamines in certain medications.

Last year, it asked several companies to voluntarily recall a common diabetes drug, named metformin, after the agency’s testing found higher-than-acceptable levels of a chemical in the nitrosamine class of compounds.

The presence of nitrosamines was also linked to widely used hypertension medications, some of which were recalled by manufacturers.

The FDA doesn’t recommend that patients taking prescription medications with potential nitrosamine impurities stop taking their medications but rather seek out physicians about concerns and other treatment options.

The FDA approved Chantix in 2006, a decision that at the time was hailed by public-health officials for its potential to help curb smoking addiction.

Safety concerns arose with reports of psychiatric side effects that eventually prompted the FDA to require a warning on Chantix’s label in 2009. Pfizer protested, and in 2016, the FDA stopped requiring the warning.

Chantix sales totaled $919 million last year, about 17% less than the previous year. The drug lost U.S. patent protection in November and started facing generic competition.

Cancer-related safety issues haven’t been detected in testing of Chantix or in individuals taking the drug who are trying to stop smoking, the Pfizer spokesman said. Smokers are up to 30 times more likely to get lung cancer than nonsmokers, he said.

Write to Jared S. Hopkins at [email protected]