Amazon has started removing dietary supplement products from its platform that contain NAC (N-acetyl-L-cysteine), several industry sources said.
The move comes nine months after FDA stated its position in warning letters that NAC couldn’t be lawfully sold in a dietary supplement because the ingredient was first approved as a drug in 1963.
The warning letters ignited alarm in the dietary supplement industry since NAC-containing products have been widely sold for many years.
A spokesperson for Amazon, which adopted polices in 2020 aimed at improving the quality of dietary supplements sold via its platform, did not immediately respond to a request for comment.
It wasn't immediately clear which NAC-containing supplements have been removed from Amazon's platform. Several dietary supplement products containing the ingredient remain available on Amazon's website, based on a cursory search.
Suzanne Shelton, a long-time public relations professional in the natural products industry, said it’s her understanding Amazon has had significant turnover in its regulatory staff. In an interview, she said it “would make sense” if new staff at Amazon removed NAC-containing products from the market if they believed this was an area where the e-commerce giant was vulnerable.
According to some sources, Amazon started removing NAC-containing products from its platform two days ago. The Natural Products Association (NPA) has reached out to Amazon to let the company know the NAC matter is “not a closed issue with FDA,” Dan Fabricant, Ph.D., NPA’s president and CEO, said in an interview.
“NAC is one of the supplements that have dual use as drug and supplement, as do fish oil, niacin, potassium, etc., that also have prescription forms,” Neil Levin, senior nutrition education manager for NOW, a prominent dietary supplement company, said in an email. “Just as not all niacin or fish oil products are sold by prescription, not all NAC is, either. And we don’t make drug claims that would warrant calling our products ‘drugs.’”
In December, the Council for Responsible Nutrition (CRN) urged FDA to reverse its position that manufacturers are barred from marketing products containing NAC as dietary supplements. CRN described the agency’s position as “legally invalid” in a letter to FDA officials.
FDA’s warning letters simply reiterate its previous conclusions that NAC is excluded from the definition of a supplement, Steven Tave, then-director of FDA's Office of Dietary Supplement Programs (ODSP), told Natural Products Insider last summer.
“To the extent that any stakeholders and anyone in industry or anyone else has facts that they think would cause us to rethink our conclusion, then we would welcome that evidence,” Tave said in an interview several months before CRN sent him the letter referenced above. “We’re happy to review it, and we would invite them to submit it to us.”
Tave, who led ODSP for five years, is now director of the Office of Strategic Planning and Operational Policy within FDA's Office of Regulatory Affairs.
An FDA spokesperson said Friday the agency "does not have any updates on its position regarding NAC."