Recently, the U.S. Food and Drug Administration (FDA) concluded that beta-nicotinamide mononucleotide (NMN) is excluded from the definition of a dietary supplement and may not be marketed as or in a dietary supplement because NMN is “an article authorized for investigation as a new drug by the FDA”.

The FDA decision is based on a provision in the Federal Food, Drug, and Cosmetic Act (FD&C Act), known as the “drug preclusion” provision, stating that if an article, in this case NMN, has been authorized for investigation as a new drug for which substantial clinical investigations have been instituted and for which the existence of such investigations has been made public, the article may not be marketed as or in a dietary supplement unless the article was marketed as a dietary supplement or as a food before being authorized for investigation as a new drug (21 U.S.C. § 321(ff)).

The FDA made this determination in a response to a New Dietary Ingredient Notification (NDI 1259) from Inner Mongolia Kingdomway Pharmaceutical Ltd (Kingdomway). Prior to releasing this response letter, the agency did not conclude that NMN was excluded from the definition of a dietary supplement due to being investigated as a drug in response letters to five New Dietary Ingredient Notifications (NDINs) filed with FDA between 2020 and 2022. Moreover, the FDA had acknowledged without objection a New Dietary Ingredient Notification for β-NMN from SyncoZymes (Shanghai) Co. Ltd on May 16, 2022 (NDI 1247).

As a result, in November the FDA sent letters communicating this new conclusion simultaneously to all firms that have submitted an NDI notification for NMN.