The joint statement by FDA Commissioner Scott Gottlieb, M.D., and Janet Woodcock, M.D., director of the Center for Drug Evaluation and Research, in late August, is the latest update in a series of developments concerning the high blood pressure and heart failure drug, valsartan, an angiotensin II receptor blocker (ARB) consumed by millions of Americans. This statement detailed the risks of consuming the drug and explained its investigations into its continued use.
Why this alarm against valsartan and the demand for its recall? Valsartan did not meet the FDA’s safety standards, said the FDA. The finding by the agency was shocking: a carcinogenic chemical compound was found in some samples of this drug. Following the discovery of N-nitrosodimethylamine (NDMA), a known oncogenic substance in some samples of valsartan in late July, the FDA ordered an immediate recall of nearly half of all valsartan prescriptions across the US. The source of contamination is being linked to a plant in China belonging to Zhejiang Huahai Pharmaceutical Co., although the connection of all samples to this plant can be established only after more investigations.
In its joint statement, the FDA spelt out an update about the use of valsartan. Following a series of investigations that began in around June/July, the FDA has concluded that if some 8,000 people take the maximum prescribed dosage of 320 mg for four years continuously of the contaminated drug, they could increase the risk of cancer by a factor of one additional case over the existing rate of incidence over their lifetime. The FDA considers this as representing the highest risk rate. At the joint statement, the FDA mentioned that though this was the highest possibility, the sample in which NDMA was found was extremely small.
Generic companies that manufacture valsartan, such as Torrent, Prinston (which was the first company to alert the FDA about this contamination in June), Teva, Bryan Ranch Prepack, Inc. and Preferred Pharmaceuticals, Inc. are among the many companies from whom valsartan has been recalled. Combination drugs in which valsartan is one of ingredients, such as valsartan and hydrochlorothiazide (HCTZ), amlodipine and valsartan and amlodipine, valsartan and HCTZ have also been recalled, but branded valsartan has not been withdrawn, according to the FDA.
The FDA has intensified its investigation, dedicating this task into the hands of a multidisciplinary task force of experts, consisting of medical doctors, toxicologists, chemists, pharmacists, analytical lab staff, communication specialists and investigators, who will be solely handling this task. The task force has been mandated to oversee the investigation and to keep track of any new developments and information that could come in from any manufacturer of valsartan and update the FDA about anything it might come across.
In the meanwhile, patients have been advised not to discontinue taking valsartan without medical supervision, as taking such drastic action could result in a number of complications including stroke. The agency is making every effort to ensure that these patients are put on medication from for noncontaminated valsartan from select pharma companies by providing a list of such brands.
The FDA is also testing all samples containing not only valsartan but also all products in the angiotensin II receptor blocker (ARB) class for NDMA. The FDA is doing this because the steps for synthesizing all other ARBs is quite similar to those of valsartan. In addition, it is also working with regulatory agencies across the globe to coordinate information from patients, plants and laboratories concerning the drug.https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm619024.htm https://www.pharmacist.com/article/fda-issues-statement-valsartan-recalls-grow https://www.drugwatch.com/news/2018/09/06/valsartan-recall-ndma-cancer-risks-faqs/