Valsartan Problems Continue, With Identification of Second Cancer-Causing Impurity

In the midst of a series of generic valsartan recalls issued in recent weeks, federal regulators indicate that they have found a second cancer-causing impurity that may have contaminated some versions of the blood pressure drugs.

Several different drug makers have indicated in recent weeks that valsartan pills distributed in recent years may have been contaminated with N-nitrosodimethylamine (NDMA), which is a known human carcinogen. This has left users of the hypertension drug with concerns about an increased risk of kidney cancer, liver cancer and other digestive tract cancers.

As part of the continuing investigation into the Valsartan problems, the FDA issued a press release on September 13, indicating that another potentially cancerous impurity has been found in versions of the generic Diovan pills distributed by Torrent Pharmaceuticals. The new impurity, N-Nitrosodiethylamine (NDEA) is also known to cause cancer in animals and is suspected of causing cancer in humans as well.

The announcement came after the FDA and the European Medicines Agency (EMA) were informed that the manufacturer, Zhejiang Huahai Pharmaceuticals (ZHP) found NDEA in several batches of the active ingredient. The FDA is now testing all recalled valsartan drugs and products still on the market for evidence of NDEA.

So far, the agency has detected NDEA in Torrent Pharmaceuticals’ valsartan 160mg tablets, lot BV47D001, and valsartan 320mg tablets from lots BV48D001 and BV49D002. Both were part of an earlier recall. The agency is still testing various products, but indicated that the testing shows that not all products made by ZHP contain the impurity.

“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,,” FDA Commissioner Scott Gottlieb said in the press release. “As we expand our investigational efforts, we’ll continue to make sure the public has the most up-to-date information. We’ll also continue to work with global regulatory agencies to learn as much as we can about how these impurities came about and how they may affect patients’ health around the globe.”

The EMA issued its own valsartan update on September 13, confirming the FDA’s findings. Health Canada also issued a similar valsartan NDEA warning.

The first valsartan recalls were announced in Europe on July 5, after batches of the active ingredient supplied by Zhejiang Huahai Pharmaceuticals in China, tested positive for NDMA. That initial recall affected about 2,300 batches of valsartan and valsartan HCTZ shipped throughout Europe and Canada. The same manufacturer made the recalled Torrent Pharmaceutical pills.

The FDA followed with its own recall announcement on July 13, indicating that the agency had launched an investigation to determine the scope of the contamination and the potential risk to consumers. The recall has been expanded multiple times and the impurities have been detected in valsartan from a number of different manufacturers.

The FDA has assigned a group of pharmacists and nurses to answer consumer’s questions about the recalls. Since the first recalls, the agency indicates it has received more than 6,000 inquiries from patients, doctors, nurses, pharmacists and academics. Inquiries can be made by calling 855-543-3784 or by sending an email to druginfo@fda.hhs.gov.

A number of consumers are now pursuing valsartan cancer lawsuits against the manufacturer, alleging that use of the contaminated drug resulted in their diagnosis.