FDA issues statement as valsartan recalls grow
Agency explains risk, details its ongoing investigation
The valsartan saga continued last week as Torrent Pharmaceuticals, Limited, expanded its recall of its valsartan products to include all unexpired lots, and FDA issued a about the agency’s ongoing investigation into valsartan products. FDA also updated its lists of and .
In its statement, FDA described the events that led up to the recall. In June, U.S. manufacturer Prinston Pharmaceuticals Inc., had contacted FDA‘s Center for Drug Evaluation and Research to inform the agency that it had stopped manufacturing valsartan products because it had detected trace amounts of N-nitrosodimethylamine (NDMA) in valsartan active pharmaceutical ingredient (API) supplied by Chinese manufacturer Zhejiang Huahai Pharmaceutical Co. Although the amounts of NDMA Prinston detected were small, FDA considers them to be unacceptable because NDMA is classified as a probable human carcinogen.
“We estimated that if 8,000 people took the highest valsartan dose [320 mg] from NDMA-affected medicines daily for 4 years (the amount of time we believed the affected products had been on the U.S. market), there may be one additional case of cancer over the lifetimes of these 8,000 people beyond the average cancer rate among Americans,” the statement says. “This estimate represented the highest possible level of NDMA exposure. It was a measure of the risk under the most extreme circumstances. Most patients who were exposed to the impurity through the use of valsartan received less exposure than this worst-case scenario.”
The statement goes on to explain that not all valsartan products were made with Zhejiang Huahai’s API, not all valsartan products have been recalled, and that patients should not stop taking their medication without consulting their health care providers and, if necessary, getting prescriptions for products that aren’t part of the recall. Furthermore, FDA is now testing all products in the angiotensin II receptor blocker (ARB) class to see if they contain NDMA because the steps for synthesizing other ARBs are similar to those for valsartan. The agency is also working with global regulatory agencies to exchange information about the results of inspections and laboratory tests, and about valsartan APIs worldwide.