Novel extraction method should not trigger automatic NDI notification, says USP

Botanical extracts that have been on the market for years should not automatically be treated as new dietary ingredients (NDIs) just because extraction methods have changed, according to the United States Pharmacopeia (USP).

In comments submitted to the Food and Drug Administration (FDA) about its NDI draft guidance, USP challenges the FDA’s view that scores of ‘old’ dietary ingredients should be subject to new NDI filings because new extraction methods such as super critical carbon dioxide extraction could change their chemical composition..

Scores of ODIs would be subject to fresh NDI filings

The FDA says: “If the changes in your manufacturing process alter the chemical composition or structure of the ingredient, the resulting compound is probably a NDI and a notification to FDA would be required."

A long list of processes FDA would likely consider to involve chemical alteration includes:

  • The use of solvents other than water or aqueous ethanol to make an extract;
  • A process which makes or breaks chemical bonds such as hydrolysis or esterification;
  • High temperature baking or cooking of an ingredient that has not previously been baked or cooked;
  • The application of nanotechnology that results in new or altered chemical properties of the ingredient.

Selective extraction should not be considered chemical modification.

But USP chief executive Roger Williams said: “We do not believe that selective extraction should be considered chemical modification.

“For example, extraction with hot water may induce more chemical reactions by hydrolysis than an extraction with an aprotic solvent, such as hexane or supercritical CO2.”

He added: “USP-NF monographs for botanical extracts also include limits for residual solvents …

“Considering the case-by-case evaluation by DSEC [USP’s Dietary Supplement Expert Committee] of the likely chemical modification from the use of solvents for extraction, we suggest making an exception to the NDI notification requirement for botanical extracts created with solvents other than water or aqueous ethanol that comply with the specifications in USP-NF monographs.”

Ingredients already on market that are listed in USP-NF should not have to submit NDI notifications

More generally, compendia published by the USP containing monographs for dietary ingredients and supplements could serve as a useful starting point in determining whether a fresh NDI is required for an ingredient already on the market, suggests Williams.

Monographs containing quality specifications for dietary ingredients and supplements were produced via a “diligent process that includes a threshold safety review of each ingredient for the purpose of determining whether to admit the monograph into the compendium”, he said.

“Compendial quality standards … address the concerns that different manufacturing processes might introduce different impurity profiles, by setting appropriate limits for impurities through USP’s flexible monograph approach.

“Accordingly, we suggest that an additional exemption to notification requirements be considered for NDIs that claim to comply with compendial standards in a USP-NF [United States Pharmacopeia and National Formulary] or DSC [Dietary Supplements Compendium] monograph.”

This would “further ease the administrative burden associated with notifications while still being protective of consumers”, he said.

USP is a scientific non-profit organization that sets standards for the quality, purity, identity, and strength of medicines, food ingredients and dietary supplements.