The U.S. Food and Drug Administration (FDA) has faulted multi-national drug company Mylan for not following through with quality control measures during the production of valsartan medicine.

Last year, valsartan was found to be contaminated with NDMA and/or NDEA at several manufacturing facilities around the world. One of those plants was Mylan’s Unit 8 at Andhra Pradesh, India. The FDA sent a letter dated Nov. 5 to Mylan saying it had failed to adequately create written procedures to ensure the valsartan active pharmaceutical ingredient (API) was properly tested and handled when the FDA performed an inspection in May of this year.

Valsartan is the generic form of Diovan, a medication used to treat high blood pressure or heart failure. The FDA recalled certain batches of valsartan in July 2018 after finding some pills were contaminated with NDMA, which is short for N-nitrosodimethylamine.

Weeks later, other batches of valsartan were found to be contaminated with NDEA  (N-Nitrosodiethylamine). Both NDMA and NDEA are chemical byproducts of manufacturing processes that use certain solvents.  Both contaminants are considered probable human carcinogens by the World Health Organization’s International Agency for Research on Cancer (WHO IARC).

Several valsartan class action lawsuits already have been filed regarding the recalled batches.

FDA Faults Manufacturers for Tainted Valsartan Medicine

The FDA inspected the Mylan plant after more than 100 lots of valsartan medicine were subject to a recall after “low levels of NDMA” were detected in some of the plant’s API, said the letter from the FDA. The company was told to follow up with FDA Form 483 in June, but the FDA alleges that Mylan “did not provide sufficient detail or evidence of corrective actions.”

According to FiercePharma, Mylan tried to blame contaminated solvents it had received from contracted manufacturers.

The FDA responded by saying that even though several contract manufacturers supplied solvents that were contaminated with NDMA or NDEA, Mylan failed to track which of its tanks were used to store the individual solvents.

“Although you acknowledged that there was no record of usage for each of the recovered solvent tanks, your response did not provide sufficient information on attempts to retrospectively reconcile the number, identification and use of the tanks,” alleged the FDA.

The FDA also reported it issued an additional warning letter to Lantech Pharmaceuticals, an Indian solvent recovery business that had loose processing procedures that could have resulted in contaminated solvents.

Huahai Pharmaceutical Co. Ltd. of China was the first company the FDA discovered had produced valsartan that was found to be contaminated with NDMA. The manufacturer indicated it revamped its facility in 2011, which inadvertently might have led to the introduction of the contaminant. Patients could have been taking the potentially tainted medication for seven years.

The FDA said in a letter to Huahai that when the factory changed its manufacturing processes to save money, it failed to account for the potential introduction of toxic byproducts such as NDMA.

Exposure to NDMA and NDEA have been linked to cancers of the tongue, esophagus, bladder, kidneys, liver, pancreas and lungs.