This story has been updated.
The Food and Drug Administration is investigating the causes of cancer-causing impurities in multiple blood pressure and heart medications, according to a new report from USA Today.
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Factory inspections of facilities in China and India in recent months have revealed a pattern of issues regarding drugs valsartan, losartan and irbesartan, either alone or in combination with other drugs.
The most recent recall involves eight lots of irbesartan manufactured by Zhejiang Huahai Pharmaceuticals.
“I think we have a federal agency that is overwhelmed in trying to keep up,” Public Citizen researcher and director Michael Carome told USA Today, noting the FDA often prioritizes inspections based on potential risk.
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The agency has been examining “a backlog of unchecked foreign drug plants” amid the increasing overseas pharmaceutical industry actors, including China’s Zhejiang Huahai Pharmaceutical and India’s Hetero Labs, both of which have been forced to recall carcinogen-tainted drugs.
But exacerbated inspection policies, investigations or recalls don’t guarantee prevention or action from drug companies to correct the problems.
Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, told USA TODAY the agency isn’t running those manufacturing plants. “Really, a lot of responsibility is on the people who manufacture and offer these drugs for sale,” she added.
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Previously:
India-based drug company Torrent Pharmaceuticals last week recalled an additional eight lots of losartan potassium tablets in addition to the two it recalled in December.
The FDA shared a notice announcing the the blood pressure and diabetic kidney disease medication contained unacceptable levels of the human carcinogen N-nitrosodiethylamine.
India's Hetero Labs has had to recall several commonly prescribed blood pressure drugs since July, including versions of losartan, valsartan and irbesartan. Find a full list of recall-related FDA updates at fda.gov.
Losartan potassium hydrochlorothiazide (Losartan) was also recalled by Sandoz Inc. in November over cancer concerns due to an impurity impurity N-nitrosodiethylamine, according to the U.S. Food and Drug Administration.
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“This impurity, which is a substance that occurs naturally in certain foods, drinking water, air pollution, and industrial processes, has been classified as a probable human carcinogen as per International Agency for Research on Cancer (IARC),” agency officials wrote in the Nov. 8 news release.
The Sandoz Inc. recall involved 100 milligram/25 milligram Losartan tablets with the lot number JB8912 and expiration date of June 2020. The affected product was not distributed prior to Oct. 8, 2018, according to the FDA.
The agency recently recalled two other blood pressure drugs for the impurity, irbesartan and valsartan. Those who take these hypertension medications should consult with a doctor or pharmacist before discontinuing use of the drug.
The American Heart Association in January announced new guidelines that lowered the threshold for high blood pressure, adding 30 million U.S. adults to the bucket of those with a condition that now affects nearly half of the American adult population.
For decades, high blood pressure was determined with a top reading of at least 140 or a bottom one of 90. According to the new guidelines, a reading of 130/80 is considered high blood pressure, a change that adds 30 million U.S. adults to the bucket of those with the condition.