FDA Reports Nitrosamine Impurity in the API RanitidineBy
The US Food and Drug Administration (FDA) reports that it has found that some medicines with the active pharmaceutical ingredient (API), ranitidine, contain a nitrosamine impurity, N-nitrosodimethylamine (NDMA) at low levels. NDMA is classified as a probable human carcinogen. Ranitidine is an H2 (histamine-2) blocker used in over-the-counter and prescription drugs, including the brand-name drug, Zantac, to decrease the amount of acid created by the stomach.
This marks a second API class with a detection of nitrosamine impurities. Since last year (2018), the FDA has been investigating NDMA and other nitrosamine impurities in angiotensin II receptor blockers (ARBs), blood-pressure and heart-failure medicines, that have “sartan” APIs, such as valsartan. For ARBs, the FDA has recommended numerous recalls as it discovered unacceptable levels of nitrosamines.
The FDA is evaluating whether the low levels of NDMA in ranitidine pose a risk to patients. “Although NDMA may cause harm in large amounts, the levels the FDA is finding in ranitidine from preliminary tests barely exceed amounts expected to be found in common foods,” said the FDA in a September 13, 2019 statement. NDMA is a known environmental contaminant found in water and foods, including, meats, dairy products, and vegetables.
The FDA said it is working with international regulators and industry partners to determine the source of this impurity in ranitidine. At this time, the FDA is not calling for individuals to stop taking ranitidine.
In a separate development, the European Medicines Agency reports that a nitrosamine impurity has been detected in some batches of ranitidine and that an EU-wide review of ranitidine has been initiated. As part of its broader investigation into nitrosamine impurities, the EMA’s Executive Director Guido Rasi has asked the EMA’s Committee for Medicinal Products for Human Use to provide guidance for avoiding the presence of nitrosamine impurities in human medicines containing chemically synthesized active substances. See related story.