Metformin Class Action Lawsuit Filed Over Cancer-Causing NDMA Contamination

A number of generic drug manufacturers face a class action lawsuit over metformin, following the revelation that some versions of the widely used diabetes drug have been distributed with the cancer-causing chemical N-nitrosodimethylamine (NDMA).

Joseph Brzozowski filed the complaint (PDF) in the U.S. District Court for the District of New Jersey on March 3, seeking class action status to pursue damages for all generic metformin users who unknowingly took the pills, unaware that they were contaminated and may increase their risk of cancer.

Actavis, Teva Pharmaceuticals, CVS Health Corporation and up to 100 as-yet identified defendants are named in the lawsuit, which indicates that the manufacturers failed to warn users and the the medical community that contaminated metformin pills may contain the known carcinogen.

“At all times during the period alleged herein, Defendants represented and warranted to consumers that their generic metformin products were otherwise fit for their ordinary uses, and were otherwise manufactured and distributed in accordance with applicable laws and regulations,” the lawsuit states. “However, for years, Defendants willfully flouted federal current Good Manufacturing Practices and ignored other warning signs that Defendants’ Metformin products contained or likely contained NDMA and/or other impurities.”

NDMA is a chemical byproduct, which is considered a carcinogen. It used to result from making rocket fuel in the early 1900s, but today is only used in laboratory experiments to induce cancer in animal test subjects.

In recent months, detection of the chemical in other drugs has resulted in wide scale Zantac recalls and valsartan recalls, after it was confirmed that dangerously high levels of NDMA were present in the popular heartburn and blood pressure medications.

Late last year, reports first warned about the potential risk that problems may also be impacting metformin, after some versions of the drug sold outside the United States tested positive for NDMA, raising concerns that metformin recalls may be necessary. However, the FDA indicated that testing of products distributed in the U.S. found that the metformin NDMA contamination levels were undetectable or below federal limits for exposure to the chemical.

Earlier this month, the independent online pharmacy Valisure filed a citizen’s petition urging the FDA to issue metformin recalls, after independent testing found levels of NDMA in certain pills that was higher than the agency’s recommended daily exposure threshold of 96 nanograms.

Metformin is sold under several brand names, including Glucophage, Carbophage, Fortamet, Diabex and Riomet. It is also often used in combination with other diabetes drugs, and is widely used worldwide.

According to the metformin class action lawsuit filed days after the recall petition, Brzozowski took metformin from April 2009 through September 2017, during which time he received a number of the products that were found to contain high levels of NDMA. The lawsuit indicates those drugs should be considered adulterated and illegally sold due to their NDMA content, which made them unfit for ordinary use.

NDMA In Zantac and Valsartan

Valisure is the same pharmacy which first raised alarms about the link between Zantac and cancer in September 2019, after finding that some pills contained 3,000,000 ng of NDMA. This led to further FDA testing, which confirmed the high levels were present in virtually all Zantac products and their generic equivalents, resulting in a widespread, and still ongoing, Zantac recall.

Concerns over NDMA drug contamination in pharmaceutical drugs began to emerge in 2018, with an investigation into a number of generic blood pressure drugs that were found to contain high levels of the chemical. This led to several rounds of recalls for valsartan, losartan and irbesartan, and investigations suggested that NDMC may have contaminated the drugs as a by-product of changes in the generic drug manufacturing process.

In response to concerns about the cancer risk with valsartan and other similar drugs, and the possibility of shortages for the hypertension drugs, the FDA established a permissible daily limit for NDMA at 96 nanograms, requiring pills that may expose users to more of the carcinogen to be recalled.

While drug makers and federal regulators indicate they are continuing to investigate the underlying cause of both the NDMA contamination, many consumers diagnosed with cancer in recent years are now pursuing valsartan lawsuits and Zantac lawsuits, alleging they may have avoided a cancer diagnosis if other treatments had been used.