Cosmic Peptides research library

FDA Category 2

The three groups in FDA's interim 503A policy for nominated bulk substances: under evaluation (1), raising significant safety risks (2), and nominated without adequate support (3).

Last reviewed · Editorial policy

While it builds the 503A bulks list, FDA sorts nominated substances into categories. For Category 1, substances nominated with enough information to evaluate, FDA does not intend to act against compounders who meet the interim guidance's conditions. For Category 2, where FDA has identified significant safety risks, and Category 3, nominated without enough support, FDA says it would consider taking action under its general enforcement policies.

The categories are an enforcement policy, not a regulation and not the list itself. A substance leaves a category when its nomination is withdrawn, which authorizes nothing. FDA's 503A page says it does not intend to place substances nominated on or after January 7, 2025 into the categories.

FDA placed 19 substances, nearly all of them peptides, in Category 2 on September 29, 2023. Five left on September 27, 2024 and twelve on April 22, 2026, each because its nomination was withdrawn or, for one, misdirected. Kisspeptin-10 is the only peptide still in the 503A Category 2.

See also

Cite this page

Text

Cosmic Peptides. (2026, November 10). FDA Category 2: glossary entry. Cosmic Peptides Research Library. Retrieved November 10, 2026, from https://cosmicpeptides.com/research/glossary/fda-bulk-substance-categories

BibTeX

@misc{cosmicpeptides_research_glossary_fda_bulk_substance_categories,
  author       = {{Cosmic Peptides}},
  title        = {FDA Category 2: glossary entry},
  howpublished = {Cosmic Peptides Research Library},
  year         = {2026},
  month        = nov,
  url          = {https://cosmicpeptides.com/research/glossary/fda-bulk-substance-categories},
  urldate      = {2026-11-10},
  note         = {Last reviewed 2026-11-10}
}

RIS

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T2  - Cosmic Peptides Research Library
PB  - Cosmic Peptides
PY  - 2026
DA  - 2026/11/10
UR  - https://cosmicpeptides.com/research/glossary/fda-bulk-substance-categories
Y2  - 2026/11/10
LA  - en
ER  -

Cite the date the page was last reviewed, November 10, 2026, as its version. Reference managers such as Zotero can save this page directly.

Changes to this page

  1. Published Five glossary terms for compounding

    Compounded drug, the 503A bulks list, FDA's interim bulk-substance categories (Category 1, 2 and 3), outsourcing facility and enforcement discretion: the terms the United States series' compounding pages rely on, each linked where it first appears in the library.

Changes of substance are listed here; wording changes are not. Every correction is also on the corrections log.

For in vitro laboratory research only. Not for human or veterinary use. This library describes chemistry, analytical methods and published laboratory research; it gives no guidance on use in people or animals.