A scientist at a China-based company that makes crucial ingredients for generic drugs warned a year before the start of a global recall that some blood-pressure pills could become tainted with potentially cancer-causing chemicals, according to court documents.
Zhejiang Huahai Pharmaceutical Co. makes active ingredients for generic drugs including valsartan, which is taken by millions of people to treat hypertension. In July 2018, valsartan made with Huahai’s products was recalled for containing N-Nitrosodimethylamine, or NDMA, a chemical that can increase the risk of cancer after prolonged exposure at the levels detected in the drugs.
People who are prescribed blood-pressure treatments often take them routinely for years. Generic valsartan, which is part of a class of drugs known as angiotensin II receptor blockers, has been sold in the U.S. for a decade. Since the first batches were recalled, there has been a global effort — and legal wrangling — aimed at figuring out how NDMA got into the drug, and whether pills should have been removed from pharmacies sooner.
