Heritage Pharmaceuticals, which does business as Avet Pharmaceuticals, Inc., is facing allegations that its generic metformin tablets contain high levels of a cancer-causing impurity.
According to Bloomberg Law, this latest metformin lawsuit was filed on March 30th in the U.S District Court, District of New Jersey, and seeks class action status on behalf of consumers who purchased Avet’s diabetes drugs. (Case No. 3:20-cv-03415)
The U.S. Food & Drug Administration (FDA) began investigating metformin last year, after Singapore recalled six lots for high levels of Nitrosodimethylamine (NDMA). NDMA is designated a probable human carcinogen by the U.S. Environmental Protection Agency, and animal studies suggest exposure may increase the risk of cancer, including gastrointestinal, kidney, and liver cancer.
While the FDA’s investigation did find NDMA in some metformin samples, the agency insisted that the levels detected were far below the recommended daily limit of 96 nanograms. As a result, the FDA declined to order any metformin recalls.
Unfortunately, those reassurances have not eased concerns over contaminated metformin in the United States. Last month, online pharmacy Valisure announced its own testing had found excessive levels of NDMA in 16 of 38 metformin samples tested. The highest levels were detected 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.
Heritage/Avet’s metformin tablets were also among those that tested positive for NDMA. Some samples contained more than 5 times the recommended daily limit, while others contained over 8 times the limit.
Valisure has since petitioned the FDA for a recall of the affected metformin lots, as well as an investigation into how NDMA came to contaminate the medications. But so far, the agency has not issued any recalls or announcements in response to the company’s findings.
Valisure also recently discovered NDMA in Zantac and other ranitidine-containing heartburn drugs. Last week, the FDA confirmed that the amount of NDMA in those medications can increase over time and ordered manufacturers to immediately recall all Zantac and ranitidine products currently on the market.
In 2018, the discovery of NDMA in generic angiotensin II receptor blockers (ARBs) led drug makers around the world to recall valsartan, losartan, and irbesartan-containing heart and blood pressure medications.