Impurities in valsartan may have been present for 4 years, pose minimal risk

The FDA announced that it has posted additional test results of valsartan showing levels of impurities that may have been present in products for up to 4 years.

“FDA based the estimates [in the results] on the highest daily dose; however, many people have taken lower doses and, therefore, their risks would theoretically be less,” according to an update on the FDA website. “FDA expects the actual cancer risk to most consumers to be lower than our estimate.”

As Cardiology Today previously reported, several lots of valsartan have been recalled since July 2018. The initial recalls were due to an impurity, N-nitrosodimethylamine (NDMA), which was found in the products being recalled. NDMA is classified as a probable human carcinogen based on laboratory test results. The presence of NDMA was unexpected and is believed to be related to changes in the way the active substance was manufactured. In September, the FDA announced a second impurity, N-nitrosodiethylamine (NDEA), was found in two companies’ valsartan products.

The FDA estimated that if 8,000 patients took 320 mg valsartan — the highest dose — with NDMA, there may be one additional cancer case during these patients’ lifetimes, according to the update. In addition, if 18,000 patients took the highest dose of valsartan with NDEA, there may be one additional cancer case.

“NDEA has a marginally lower cancer risk estimate than NDMA because NDEA levels were lower than levels of NDMA in drug samples,” according to the update.

The test results include the average impurity levels in a single tablet, according to the update. In addition, the results include information on whether impurities were or were not present and if levels were below the limit of detection for the testing method used by the FDA.

A list of valsartan products tested in this laboratory analysis with information on their NDMA and NDEA levels can be found on the FDA website.