Citing “competing agency priorities,” the Food and Drug Administration said in a recent letter it has not reached a substantive decision on a citizen petition pertaining to NMN in dietary supplement products.

In March, the Natural Products Association (NPA) and Alliance for Natural Health USA requested FDA determine NMN (β-Nicotinamide Mononucleotide) is not excluded from the definition of a dietary supplement or commit to exercise enforcement discretion regarding the selling of NMN as a supplement.

“We are advising you, in accordance with 21 CFR 10.30(e)(2), that we have not reached a decision on your petition within the first 180 days due to competing agency priorities,” Cara Welch, Ph.D., director of FDA’s Office of Dietary Supplement Programs (ODSP), wrote to NPA and the Alliance for Natural Health USA. “However, be advised that our staff is evaluating your petition.”

The citizen petition was filed after FDA in the fall of 2022 concluded NMN cannot be lawfully marketed in dietary supplement products. According to FDA, NMN has been authorized for investigation as a new drug and is the subject of substantial clinical investigations that have been instituted and made public.

Prior to its conclusion above, FDA had acknowledged without objection a new dietary ingredient (NDI) notification for NMN in dietary supplement products. FDA later explained it had not immediately made the connection between NMN and MIB-626, the ingredient under investigation as a new drug by Metro International Biotech.

NPA President and CEO Dan Fabricant, Ph.D., said the NMN petition should be an agency priority because it is a public health matter relating to the NDI notification process. That process is required under the Dietary Supplement Health and Education Act of 1994 (DSHEA) to demonstrate the safety of novel ingredients.

He has been critical of FDA’s reversal of the acknowledgement or so-called good day letter it sent in May 2022 to a Chinese manufacturer of NMN, SyncoZymes (Shanghai) Co. Ltd.

He characterized FDA’s move as “acknowledgement until proven bankrupt” or more broadly, “basically taking the NDI process and throwing it out.”

FDA’s decision, industry sources have said, has had an enormous adverse impact on the NMN market. Amazon, the world’s largest retailer, prohibited its merchants from selling NMN supplements beginning in March.

According to a press release from Market Reports World, the global NMN market was worth an estimated US$280.2 million in 2022.

Fabricant predicted FDA “is just going to run clock” on the citizen petition, with the eventual consequence of other platforms stopping sales of NMN. FDA may go several years without responding substantively to such a petition.

“If I’m in the NMN business or new ingredient business, this is where the industry has to stand tall and probably pursue … some form of litigation, because you’re not going to get relief otherwise,” he told Natural Products Insider. “FDA’s just going to wait you out.”

Rob Verkerk, Ph.D., executive and scientific director of the Alliance for Natural Health USA, said his organization “is disappointed, but not surprised, by the FDA's continued inaction on NMN.”

“The FDA knows perfectly well that the IND [investigational new drug] rubber stamp gives preferential treatment to its paymasters, the drug companies, while working against wider, low-cost access to highly effective dietary supplements like NMN,” Verkerk said in an email to Natural Products Insider. “Without congressional intervention, it looks likely that we'll need a lawsuit if we're going to successfully rein in the FDA's bias against natural products through the use of IND submissions."