FDA declines lawmaker’s request for public hearing on NMN

On July 17, FDA declined a request by U.S. Representative Jeff Duncan (R–SC) to hold a public hearing to clarify the agency’s recent stance that nicotinamide mononucleotide (NMN) is not allowed in dietary supplements. Last year, in response to several New Dietary Ingredient notifications (NDINs) submitted by companies using NMN in dietary supplements, FDA stated that NMN is not a legal dietary ingredient. The agency said that NMN was first studied as a drug before it was marketed as a supplement, and that due to the drug preclusion clause of the Federal Food, Drug, and Cosmetic Act (FD&C Act), NMN is therefore disqualified as a dietary ingredient for supplements.

Critics of FDA’s position have asked the agency to substantiate its stance on NMN, noting that in other previous NDINs, the agency did not object to NMN’s use in supplements. Following FDA’s negative response to the NMN NDINs last year, retailers like Amazon began banning NMN supplements from retail.

Many dietary supplement associations oppose FDA’s latest position on NMN’s legal stance in supplements. In March 2023, the Natural Products Association (NPA; Washington, DC) and the Alliance for Natural Health (ANH; Edinburg, VA) submitted a citizen petition to FDA asking the agency to provide more explanation and to affirm the legality of NMN in supplements. (Another industry association, the Council for Responsible Nutrition (Washington, DC), has also submitted a citizen petition asking FDA to modify and clarify its overall stance on the drug preclusion clause.)

According to FDA’s response letter to Rep. Duncan, the lawmaker had on April 27, 2023, requested that FDA hold a public hearing “to clarify the Food and Drug Administration’s position on the use of nicotinamide mononucleotide (NMN) in dietary supplements.” In a letter to Duncan’s office, FDA wrote that it does not plan to hold a public hearing on NMN. The agency stated that it is currently reviewing NPA’s and ANH’s citizen petition, which was posted on Regulations.gov (FDA-2023-P-0872-0001) and open for public comment. “In light of this opportunity for the public to provide information and views that FDA will consider as part of our work in reviewing and responding to the citizen petition, we do not believe that it is in the public interest to hold a public hearing on this matter,” FDA wrote to Duncan.

Duncan had also asked FDA a list of questions about NMN. In its response to Duncan, FDA addressed some of the questions. Most of the agency’s responses state that many of the points are currently under review as the agency works on responding to the NPA/ANH citizen petition, and thus the agency declined to provide specific answers, including information about the date FDA is using to determine when NMN was first marketed as a dietary supplement.

Some of the affirmative responses FDA did provide in its response to Rep. Duncan include statements that: 1) “FDA has not contacted any e-commerce platforms regarding the sale of NMN-containing products,” 2) the agency estimates that as of May 10, 2023, it has received “at least” 42 structure-function claim notifications for NMN-containing products, with the agency raising objections to at least 10 of those notifications, and 3) the agency has not taken any enforcement actions to address the marketing of NMN products by companies submitting NDINs.

The agency’s response letter also cautions that “FDA’s silence on an ingredient’s regulatory status in a response to a structure-function claim notification, or the lack of an FDA response to a structure-function notification, should not be read as a statement that the ingredient is lawful for use in dietary supplements.”

In learning that FDA declined to hold the public hearing requested by Rep. Duncan, Daniel Fabricant, PhD, NPA’s president and CEO, issued a statement: “FDA has completely abdicated its duty to transparency and appropriate regulatory practice for dietary supplements, and this is the latest proof. A public comment period and a public hearing are entirely different, and the agency knows that.”