Classes

Peptide classes

By Diane Walker · Reference Editor

A class groups molecules by what they do rather than by what United States law permits, which is why the class hubs are the most useful cross-cut on this site: they put a molecule with an approved product next to one with no lawful route at all, and make the gap between pharmacology and regulation legible in a single table.

The membership of every class below is read from the registry, so a molecule cannot sit in a class whose hub does not exist, and a hub cannot exist for a class the registry does not hold. A class publishes at 2 molecules; below that it is a stub rather than a page, and the build refuses it. Of the 10 distinct classes the registry currently holds, 10 clear that floor and none is withheld; the published hubs account for 35 of the 35 molecules in the index.

  1. GH secretagogues

    Tesamorelin, sermorelin, CJC-1295, and ipamorelin span every legal posture in this index — approved, compoundable, and no lawful route. The comparison, dated.

    6 molecules · 4 postures: FDA-approved, Compoundable (503A), Nomination withdrawn, No lawful route

  2. GLP-1 receptor agonists

    Semaglutide and tirzepatide anchor the approved end of this index: deep trial records, and supply rules that changed sharply in 2026. The class, dated.

    4 molecules · 2 postures: FDA-approved, No lawful route

  3. Growth factor fragments

    AOD-9604 and PEG-MGF are fragments of growth-axis proteins sold for body composition, with more regulatory record than human evidence. Dated.

    3 molecules · 2 postures: No lawful route, Nomination withdrawn

  4. Gut peptides

    Secretin and vasoactive intestinal peptide share a structural family and split every regulatory question between them. Verified September 2026.

    2 molecules · 2 postures: Compoundable (503A), FDA-approved

  5. Immune peptides

    LL-37 and thymosin alpha-1 are immunomodulators with no US route. One has a large foreign trial record; the other's count is mostly misread. Dated.

    3 molecules · 2 postures: No lawful route, Nomination withdrawn

  6. Longevity peptides

    Epitalon and L-carnosine are sold on the same promise and sit at opposite ends of the evidence range. Neither has a lawful compounding route. September 2026.

    2 molecules · 2 postures: PCAC-recommended · pending, No lawful route

  7. Melanocortins

    Melanotan II and PT-141 share a receptor family and nothing else: one is an approved drug with a label, the other left the bulks list. Dated.

    2 molecules · 2 postures: No lawful route, FDA-approved

  8. Mitochondrial

    NAD+ and MOTS-c are marketed side by side and sit on opposite sides of US compounding law. What the evidence and the statuses actually are, dated.

    3 molecules · 2 postures: Compoundable (503A), PCAC-recommended · pending

  9. Neuropeptides

    Cognition, mood, stress, and sleep peptides occupying four different positions on FDA's lists — recommended, refused, unreviewed, and prohibited. Dated.

    5 molecules · 3 postures: PCAC-recommended · pending, No lawful route, Nomination withdrawn

  10. Repair peptides

    BPC-157, TB-500, and GHK-Cu — the injury-and-recovery peptides — share a market and a gray zone. Votes, evidence gaps, and dates, verified August 2026.

    5 molecules · 2 postures: PCAC-recommended · pending, No lawful route

The other way through

A class answers what a molecule is; a status answers what may lawfully be done with it. The approved, compoundable, pending and no lawful route pages carry the same molecules filed the other way, and the molecule index holds every row at once.