A third type of cancer-causing impurity has been found in a type of high blood pressure and heart failure medication from a class of drugs known as ARBs (angiotensin receptor blocker), the Food and Drug Administration (FDA) announced in a news release. The impurity N-Nitroso-N-methyl-4-aminobutyric acid (NMBA), was detected in losartan potassium tablets made by Hetero Labs Ltd., and distributed by Camber Pharmaceuticals. As a result, Hetero Labs recalled 87 lots of the pills in 25mg, 50mg, and 100mg dosages.
Since last summer, the FDA has issued numerous recalls of the ARBs losartan, valsartan and irbesartan mainly due to the presence of NDMA (N-nitrosodimethylamine) and/or NDEA (N-Nitrosodiethylamine. The recall of losartan by Hetero Labs was issued because the level of NMBA in the drug was higher than the FDA’s interim acceptable intake limits. The agency said that the cancer-causing agent may have been generated when specific chemicals and reactions conditions are present during the manufacturing of the drug’s active pharmaceutical ingredient.
“We are deeply concerned about the presence of a third nitrosamine impurity in certain ARB medications, but it’s important to underscore that, based on the FDA’s initial evaluation, the increased risk of cancer to patients with NMBA exposure appears to be the same for NDMA exposure but less than the risk from NDEA exposure. That said, any presence of such impurities in drug products is not acceptable,” the FDA said.
The FDA is continuing its investigation into ARB drugs and the risks nitrosamines pose to consumers. As part of this process, the agency will continue to test all ARBs for nitrosamine impurities. “If NDEA, NDMA, NMBA or other nitrosamine impurities are found in drug products at levels above the interim acceptable intake limits, the FDA will work with companies to swiftly remove affected products from the market.”
Additionally, the FDA will continue to update the list of recalled ARBs as more information becomes available from ongoing testing.
FDA News Release