Lawsuits over allegedly contaminated metformin tablets are beginning to mount in courts around the United States.
One of the most recent cases was filed late last week in the U.S. District Court, Southern District of Florida, and seeks class action status on behalf of health insurance companies that paid for “worthless” diabetes drugs. (Case No. Case 1:20-cv-21456)
Metformin is the most widely prescribed oral treatment for Type 2 diabetes.
Last year, however, regulators in Singapore recalled six lots of metformin tablets for high levels of Nitrosodimethylamine (NDMA), a probable human carcinogen. Similar metformin recalls have since been announced in Canada.
The U.S. Food & Drug Administration (FDA) began testing metformin last year in response to the Singapore recalls. While those tests did detect NDMA in some samples, the agency maintained that the levels were well below its recommended daily limit of 96 nanograms. As a result, the FDA has yet to order any metformin recalls in the United States.
Just last month, however, the online pharmacy Valisure announced that excessive levels of NDMA had been detected in 16 of 38 metformin samples tested. The highest amounts were found in Amneal Pharmaceutical’s metformin, which in some cases contained as much as 16-times the FDA’s recommended daily limits. Several companies’ metformin contained more than 10 times the limit.
Valisure has requested that the affected metformin lots be recalled, but the FDA has yet to respond to the company’s petition.
MSP Recovery Claims, the lead plaintiff in the Florida metformin lawsuit, accuses various generic drug companies, including Arobindo, Aurolife Pharma, LLC, Heritage Pharmaceuticals, LLC, and Emcure Pharmaceuticals, of concealing the NDMA contamination and committing “pervasive” violations of current Good Manufacturing Practices (cGMP). The defendants’ metformin tablets were also among those found to contain high levels of NDMA by Valisure’s testing program.
As the complaint notes, NDMA is one of 66 chemicals designated “probably carcinogenic to humans” by the World Health Organization. The U.S. Environmental Protection Agency has also classified NDMA as a probable human carcinogen by giving it a “B2” rating. Those designations are based on animal studies suggesting exposure to NDMA may increase the risk for cancer, especially gastrointestinal, kidney, and liver cancer.
“Accordingly, NDMA is not an FDA-approved ingredient for Glycophage or generic Metformin. None of Defendants’ Metformin drugs (or any Metformin product, for that matter) identifies NDMA as an ingredient on product labels or anywhere else,” the complaint states. “If Defendants had not routinely disregarded the FDA’s cGMPs and deliberately manipulated and disregarded sampling data suggestive of impurities, or had fulfilled their quality assurance obligations, Defendants would have found the NDMA contamination almost immediately.”