The recall from the U.S. of tainted blood pressure medicines reached new heights as India’s Torrent Pharmaceuticals recalled 104 lots of losartan over the weekend because they contained an impurity suspected of causing cancer.
According to an FDA notice, Torrent has recalled 36 lots of losartan potassium tablets USP and 68 lots of losartan potassium/hydrochlorothiazide tablets, USP in a variety of dose strengths after it learned the API from Hetero Labs from which they were made contained N-methylnitrosobutyric acid (NMBA) that exceeds acceptable levels. The recall added up to more than 1.07 million bottles.
Torrent is recalling only those lots in which the NMBA exceeds a level the FDA considers safe. At the same time, the FDA says there is more risk of heart attack or stroke for patients that stop taking their drugs than from getting cancer from drugs that contain the elevated levels of the impurity. The agency recommends patients check with their doctors or pharmacies about alternatives before they quit their losartan.
Recently departed FDA Commissioner Scott Gottlieb and Janet Woodcock, director of the Center for Drug Evaluation and Research, said agency scientists believe using the tainted drugs temporarily wouldn't raise cancer risks in a "meaningful" way.
“After careful evaluation of safety data and consideration of the benefits and risks to patients, we think it’s critical that patients have access to these drugs while impurity-free losartan is manufactured,” the Thursday statement said.
The FDA several weeks ago had included some doses of Torrent losartan, valsartan, telmisartan and olmesartan medoxomil on a list of drugs that the FDA has been testing for three impurities that have been found in blood pressure medications since the global recall process began nine months ago. Drugs from about 40 makers were found to be free of the higher levels of impurities, but the Torrent drugs were among those for which the FDA had yet to complete testing.
The initial discovery of tainted sartan products came last summer after a U.S. drug manufacturer found NDMA at a high level in the API for valsartan that it got from a Chinese supplier. Since then, the FDA discovered that NDMA, NMBA and NDEA, all which are considered unsafe at certain levels, can be created during certain manufacturing situations for sartan drugs, including the reuse of solvents.
The surprise findings set off global recalls of hundreds of lots of valsartan, irbesartan and losartan and an intensive FDA investigation into how it could have happened and the dangers it poses to U.S. consumers. In the meantime, shortages have developed. The FDA this month approved a new impurity-free generic, Diovan, to help relieve shortages flowing from massive recalls.