FDA statement on its ongoing investigation into valsartan impurities and recalls

In a statement, FDA Commissioner Scott Gottlieb, MD, and Janet Woodcock, MD, director of FDA's Center for Drug Evaluation and Research (CDER), provide an update on the agency's investigation into an impurity, NDMA, found in some generic versions of the blood pressure medication valsartan.

In a statement, FDA Commissioner Scott Gottlieb, MD, and Janet Woodcock, MD, director of FDA's Center for Drug Evaluation and Research (CDER), provide an update on the agency's investigation into an impurity, NDMA, found in some generic versions of the blood pressure medication valsartan. A dedicated task force--made up of chemists, toxicologists, medical doctors, pharmacists, investigators, communication specialists, and analytical lab staff--is investigating the issue. The FDA officials review the steps the agency has taken thus far, starting when Prinston Pharmaceuticals Inc. contacted CDER in June about its products containing valsartan API manufactured by Zhejiang Huahai Pharmaceutical Co. (ZHP). Prinston said it had stopped making valsartan products because ZHP had detected NDMA in the API. NDMA is a probable cancer-causing chemical found in trace amounts in water and some foods. "Although the risk to patients taking the affected products is extremely low, we take matters of pharmaceutical quality very seriously," note Gottlieb and Woodcock. FDA determined that "a combination of conditions, which include certain chemicals, processing conditions and production steps, could lead to formation of the NDMA impurity. We believe that these risks are introduced through a specific sequence of steps in the manufacturing process, where certain chemical reactions are needed to form the active ingredient." Still, they note they "are still not 100% sure that this is the root cause of the problem." FDA is now "testing all the products in the ARB class to determine if they contain NDMA. ... These tests will continue until we identify all products that may contain NDMA in the ARB class, and they are no longer available in the U.S." The FDA officials note that the agency will continue its investigation and will provide updates, including advice for patients and prescribers, along the way. "This is a serious matter that is being managed closely by the FDA's leadership," Gottlieb and Woodcock assert.