FDA Determines that Homotaurine is Not a Dietary Ingredient, and Punts on Applicability of Its Rulemaking Authority Under FDC Act §§ 201(ff)(3)(B) and 301(ll)

By Ricardo Carvajal –

FDA denied a citizen petition filed on behalf of OVOS Natural Health, Inc. (“OVOS”) that asked the agency to issue a regulation under FDC Act § 201(ff)(3)(B) or § 301(ll) acknowledging that marketing of homotaurine as a dietary ingredient in dietary supplements is permissible.  OVOS filed the citizen petition because OVOS had not marketed homotaurine as a dietary supplement or food before OVOS obtained authorization for an IND pursuant to which at least two substantial clinical investigations have been instituted and made public; thus, FDC Act § 201(ff)(3)(B) appeared to prohibit the marketing of homotaurine as a dietary supplement, and FDC Act § 301(ll) appeared to prohibit its addition to food.  However, both sections contain provisions that authorize FDA to issue a regulation that essentially waives their applicability to a particular substance.  

In its response, FDA concluded that the request to exercise its rulemaking authority under FDC Act § 201(ff)(3)(B) or § 301(ll) was moot because homotaurine is not a dietary ingredient within the meaning of FDC Act § 201(ff)(1)(A)-(F).  FDA determined that homotaurine is not an “amino acid” under FDC Act § 201(ff)(1)(D) because it is a gamma-amino sulfonic acid, and not an alpha-amino carboxylic acid or a constituent of proteins.  FDA also determined that OVOS’s homotaurine does not qualify as a botanical (or extract thereof) because it is made synthetically.  Further, FDA determined that there was no evidence that homotaurine “has ever been a dietary substance for use by man to increase the total dietary intake.”

FDA’s response is worth reading for its lengthy discussion of the agency’s interpretation of the term “amino acid” in the context of dietary supplement regulation.  The response also suggests that FDA can be expected to closely scrutinize the applicability of the definition of “dietary supplement” to synthetic substances that are not already part of the food supply.