Multiple stocks of valsartan medication were recently recalled from the market due to concerns of an NDMA contamination, which was allegedly caused by a change in a manufacturing process at a Zhejiang Pharmaceuticals plant in China.

While numerous valsartan stocks sourced from this plant may have been contaminated, not all valsartan products were affected and are still safe to take. According to a recent update from the FDA on April 5, 2019, the agency released a list of 40 angiotensin II receptor blocker medications that are free from nitrosamines contamination.

This list will help medical professionals evaluate whether or not valsartan is an ideal treatment choice for their patients with high blood pressure. This list should also provide a good guideline of which medications not to prescribe.

Valsartan is part of the angiotensin II receptor blocker (ARB) drug family, which are often prescribed to treat patients with high blood pressure and hypertension. These medications work by blocking angiotensin, which are protein hormones that constrict blood flow. These drugs can also help alleviate conditions like heart failure.

While the potential nitrosamine contamination started with certain valsartan stocks sourced from Zhejiang Pharmaceuticals, the FDA has since announced recalls of other ARB medications. Nitrosamines are environmental contaminants found in water and foods and have been known to cause cancer.

It has been said that when nitrosamines have a reaction with a wastewater contaminant called dimethylamine and monochloramine, the reaction could produce N-nitrosodimethylamine (NDMA). It is important to note that NDMA, often produced as a byproduct of manufacturing processes, is classified as a potential human carcinogen based on laboratory tests.

According to the FDA’s ongoing review, the agency stated “the maximum possible exposure to nitrosamines … in ARB medicines appears to be small,” but the contamination is not acceptable for patients.

The recent list of 40 ARBs will be added to the FDA’s safe list, with the agency continuing to work with manufacturers to remove contaminated medications that have unacceptable levels of nitrosamine impurities.

Overview of Valsartan Contamination Saga

The contaminated valsartan medication stocks were first reported on in May 2018 by the European Medicines Agency, which announced that a potentially dangerous impurity had been discovered in medications sourced from Zhejiang Huahai Pharmaceuticals.

The impurity had been found to be NDMA, which reportedly made the medications useless in their purpose and put patients at an increased risk for cancer.

European health officials began recalling affected valsartan stocks from the market, along with urging pharmacies to pull valsartan products from their shelves. The FDA reported on this in July 2018, with the agency stating it had asked three manufacturers of generic valsartan medication to voluntarily recall their products from the market.

It is important to note that these valsartan recalls have caused shortages in the market, with the FDA stating it is working to resolve them. One potential solution proposed by health authorities is to allow the drug losartan to be available, which was also reportedly affected by the contamination.

The FDA stated it should take six months for uncontaminated losartan to become available to the market.

“Our scientists feel that this will not have a meaningful increased risk for cancer over the time it should take to get impurity-free losartan to market,” the FDA stated.