- The Food and Drug Administration and the European Medicines Agency both issued updates into the investigation of the voluntary recall of a number of high blood pressure drug valsartan products following discovery of N‑nitrosodimethylamine (NDMA) contamination.
- The FDA's latest round of testing has revealed an additional impurity, N-nitrosodiethylamine (NDEA) in three lots of Torrent Pharmaceuticals' recalled valsartan products. NDEA is a known animal carcinogen and a suspected human carcinogen.
- The source of the impurity was the valsartan active pharmaceutical ingredient (API) from Zhejiang Huahai Pharmaceuticals. Not all products made from Zhejiang Huahai's valsartan contain the impurity, however.
The ongoing valsartan saga dates back to June, when small but unacceptable amounts of NDMA were found in the API sourced from Zhejiang Huahai Pharmaceutical.
More than half of valsartan products are now under recall and FDA said last month more are likely.
The story has now escalated. Once the FDA and EMA learned that Zhejiang Huahai discovered an additional impurity, NDEA, the authorities retested all valsartan API and products. Like NMDA, NDEA appears to be formed as a result of a specific sequence of steps in manufacturing.
"As we continue to investigate the root cause of the impurities found in products that contain valsartan, our scientists are testing these products to better understand these impurities and to ensure they’re not present in other products. We’re also taking steps to make sure we’re providing stringent oversight of manufacturing processes to reduce the likelihood that impurities could be introduced into other products," FDA Commissioner Scott Gottlieb said in a statement.
The FDA is evaluating the potential risk from NDEA, and will work with companies to arrange recalls if it is found in any further products. Additionally, the agency said it will keep the public and the recalled product list updated, and will keep working with global regulatory agencies to find out how the impurities came about and how they may affect patients' health.
The EMA, meanwhile, has been working on calculating the risk from taking valsartan medicines containing NMDA, and has concluded that the lifetime risk of cancer is low (around one in 5,000) for someone who has taken the highest dose between July 2012 and July 2018. The European agency is also assessing the risks associated with NDEA.