Among a flurry of press releases from the FDA in Scott Gottlieb's last days as its commissioner, the agency released a list of 40 angiotensin receptor blockers (ARBs) free from potentially carcinogenic nitrosamine impurities. The list included candesartan, olmesartan, telmisartan, and valsartan products -- many in fixed-dose combination pills with other antihypertensives -- by a range of manufacturers. The ranks of "clean" ARBs is anticipated to increase as the FDA completes thorough testing and assessment on each product, according to a statement from Gottlieb and and Janet Woodcock, MD, director of the FDA Center for Drug Evaluation and Research. Also, although the FDA decided to temporarily ease the contamination standards for losartan to head off a looming drug shortage, "the agency expects many companies will be able to manufacture losartan without nitrosamine impurities and replenish the U.S. supply in approximately six months," it said. The statement detailed steps the agency has been taking with industry, including a letter to manufacturers informing them of specific chemicals and reaction conditions that contribute to formation of nitrosamine impurities and warning about contaminated (especially reused) raw materials, "even if it is not disclosed by their supplier." "Despite the very low risks associated with the use of affected ARBs, we fully recognize that these medications can be made without nitrosamine impurities and are working with manufacturers to reach that goal," the statement noted. Source
