Over the past three years, millions of blood pressure pills that contain a probable carcinogen have been recalled around the world. As pharmaceutical companies have worked on finding a fix, they’ve discovered an entirely new problem: Another potentially dangerous chemical is showing up in the same drugs.
The new chemicals are called azido impurities and regulatory authorities say they’re mutagenic, meaning they can change someone’s DNA and potentially increase cancer risk.
The impurities were found in blood pressure drugs which have been recalled in Canada as well as Europe earlier this year. U.S. officials helped lead the way in the 2018 recalls of the same type of drugs tainted with the probable carcinogen N-Nitrosodimethylamine, or NDMA, though they have yet to pull any for containing the azido impurities.
Meanwhile, a U.S. Food and Drug Administration inspector has found at least one large manufacturer in India, Hetero Labs Ltd., has a flawed process for controlling the impurities, according to documents reviewed by Bloomberg. Hetero also hasn’t adequately ensured a residue of impurities aren’t building up on production equipment, which can cross-contaminate subsequent batches, according to the documents.
The FDA inspector visited Hetero Labs Ltd.’s production plant in the Sangareddy district in south central India over 10 days in August. The plant makes the active ingredient for the blood pressure drug called valsartan, which it sells to other pharmaceutical companies to make a finished pill. Valsartan production can form azido impurities. The company did not respond to requests for comment.
Drug regulator Health Canada announced recalls of valsartan, a type of drug called an angiotensin II receptor blocker or ARB, in May for elevated levels of azido impurities. Over the next few months, other drugs in the same class, losartan and irbesartan, were recalled for the same impurities. Companies implicated include Sanofi, Novartis AG’s generic-drug unit Sandoz and generic-drug giant Teva Pharmaceutical Industries Ltd.
