Peptide Names Decoded: Where BPC-157, TB-500, GHRP-6 and -relin Come From

Why peptide names come in layers

Take GHRP-2, a six-residue growth hormone-releasing peptide. It is GHRP-2 in research catalogues; pralmorelin as an INN; KP-102 as a development code; pralmorelin dihydrochloride under its US adopted name and pralmorelin hydrochloride under its Japanese one, with the trade name GHRP; and it has at least two CAS Registry Numbers, 158861-67-7 for the peptide and 158827-34-0 for the dihydrochloride (PubChem; KEGG). Every one of those names refers to the same chain, D-Ala-D-2Nal-Ala-Trp-D-Phe-Lys-NH2.

The layers exist because different people needed a name at different times: chemists naming a series, a company tracking a candidate, regulators needing one public name per substance and registries needing a number for each form. Knowing which layer a name comes from tells you how much weight it can bear.

International Nonproprietary Names and WHO stems

WHO’s INN Programme selects one generic name per pharmaceutical substance, and “Each INN is a unique name that is globally recognized and is public property.” Related substances are meant to look related, because “Stems define the pharmacologically related group to which the INN belongs.” The table gives WHO’s definitions of the INN stems that matter most in a research catalogue, with examples confirmed in KEGG, PubChem or WHO’s own lists. Our growth hormone peptides research map shows how the -relin family fits together.

Three cautions apply to peptide naming by stem. Stems can be redefined: the February 2026 addendum widened -morelin from “peptides” to “substances” without stating why, and an earlier addendum widened -glutide to “analogues and agonists”. Pre-stems are provisional; WHO describes a pre-stem as “similar to stem, but it didn’t reach the stage of stem yet”. And national names usually, not always, match: WHO says British, French, Japanese and US names “are nowadays, with rare exceptions, identical to the INNs”, yet the INN leuprorelin is leuprolide under its US adopted name. Salts add a layer of their own: KEGG lists sermorelin (INN) and sermorelin acetate (USAN) separately.

Developer code names: letters, numbers and history

Before a molecule gets an INN, if it ever does, it is tracked by a code: letters for a company, institute or project and a number from an internal series. Peptide code names help when searching old papers and patents, but their meanings are rarely published, and a guessed expansion repeated as fact is how folklore starts.

CJC-1295 was developed at ConjuChem in Montréal: the 2005 paper that identified it among albumin conjugates of hGRF(1–29) came from the company’s research department, and three authors of a 2006 paper on the compound were at ConjuChem, Inc. The letters match the company name, but we found no ConjuChem document spelling out the prefix, and nothing explains the number. The name first belonged to that albumin-binding analogue; “CJC-1295 without DAC” is a market label for a different molecule that lacks the albumin-binding group.

AOD9604 is “Tyr-hGH177-191”, residues 177–191 of human growth hormone with an added N-terminal tyrosine; the published safety paper, one of whose authors was at Metabolic Pharmaceuticals, thanks the company for “funding all six clinical trials”. AOD is often expanded as “anti-obesity drug”, but that paper never spells the letters out, and we could not confirm the expansion in a primary source, so regard it as reported rather than established. Our AOD-9604 guide covers the research history.

BPC 157 is the case where the expansion is documented and the number is not. A 2025 literature and patent review describes it as “known as the ‘Body Protection Compound’”, a pentadecapeptide isolated from human gastric juice, first described by Sikirić and colleagues in 1993 and also known as PLD-116, PL-10, PL14736 or Bepectin. “Body protection” is a historical name, not a demonstrated property, and we found no source explaining the 157.

GHRP, finally, is a descriptive class name with series numbers. In a 1998 paper, C. Y. Bowers calls the family “Growth hormone-releasing peptides”, and the numbers do not give residue counts: GHRP-2 and GHRP-6 are both six residues long.

Sequence names: when the name is the sequence

The third system needs no lookup, only the amino acid codes. Some names are a one-letter sequence written out, as GHK and KPV are. Others give a fragment of a parent protein by residue numbers: GHRH(1–29)NH2, a PubChem synonym for sermorelin, is the first 29 residues of growth hormone-releasing hormone with a C-terminal amide; Tyr-hGH177–191 is AOD9604; and ACTH(4–7)PGP, the name a 2020 paper uses for Semax, is residues 4–7 of ACTH followed by Pro-Gly-Pro.

A third pattern combines the first residues with the length. UniProt’s human cathelicidin entry lists LL-37, which begins Leu-Leu and is 37 residues long, alongside LL-29, LL-23, FF-33, RK-31, KS-30 and KR-20, all read the same way, and FALL-39, the 39-residue form that begins Phe-Ala-Leu-Leu. Kisspeptin-54, -14, -13 and -10 follow a simpler rule: the number is the length, counted back from the shared amidated C-terminus. Names like these can be decoded and checked directly against a stated sequence and a measured mass.

Same name, different molecule, and the reverse

Market names have no owner and no definition, so they drift, and TB-500 is a well-documented case. Thymosin beta-4 is a natural 43-residue peptide, but in 2012 anti-doping chemists at Ghent University reported finding “the N-terminal acetylated 17-23 fragment of human thymosin beta 4”, seven residues long, in a product sold as TB-500. The name is still attached to more than one molecule, so on its own it does not say which is meant. We found no primary source for who coined the name or what its number means; our sibling article on two unrelated peptides that share the thymosin name explains the family name itself.

CJC-1295 shows the same drift: the name appears both on the albumin-binding analogue it first described and, as “CJC-1295 without DAC”, on a different molecule. Even large databases slip: on 21 October 2026, the PubChem record for GHRP-6 (CID 4345065, C46H56N12O6) listed “GHRP-2 Acetate” among its depositor-supplied synonyms, though GHRP-2 is a different peptide, C45H55N9O6. The reverse also happens, with one molecule under several names: GHRP-2 and pralmorelin, or leuprorelin and leuprolide.

Modifiers in a product name deserve as much attention as the core. “No DAC”, “fragment”, “N-acetyl” and “amidate” each signal a different molecule from the parent, with its own formula and mass, and our catalogue lists such variants as separate products. Not every research peptide has an INN to fall back on, either: GHRP-2 has one, while the PubChem record for GHRP-6 lists none.

Checking the identity behind a name

Identity is settled by data that a name cannot carry. The table shows what each common identifier pins down and what it can miss.

Read the name, then the full sequence and formula, then check the certificate: any mass it reports should match the capped, bridged sequence, and its batch number should match your vial.

What’s established and what isn’t

Searching for a compound in a Canadian catalogue

Our catalogue lists peptides under their research-market names — GHRP-2 rather than pralmorelin, Sermorelin rather than GHRH(1–29)NH2 — so search more than one way, on our site or anyone else’s, and apply the same checks to every supplier, including us.

• Try the market name, the INN and any code, with and without hyphens or spaces: GHRP-2, GHRP 2, pralmorelin, KP-102.
• Expect French forms. WHO’s cumulative INN list gives each name in Latin, English, French, Spanish, Arabic, Chinese and Russian, so a French-language Canadian source may use the French form of the same name.
• When names disagree, compare sequences; a run of residues is harder to misattribute than a name.
• Check that the listing gives a sequence, caps, formula and mass, and that the certificate matches them. If anything is missing, ask through our contact page before ordering.

Pure Peptides Canada is a Canadian-owned supplier based in Toronto, with prices in Canadian dollars and tracked shipping from inside Canada.

The names in our catalogue

BPC-157, TB-500, GHRP-6 and the -relin peptide ipamorelin are all in our catalogue. As this guide explains, a name is not proof, so check the Janoshik test report for each one on our Lab Testing page.

BPC-15715-amino-acid research peptideView product TB-500Listed as thymosin beta-4View product GHRP-6Growth hormone-releasing hexapeptideView product IpamorelinPentapeptide GH secretagogueView product

Frequently asked questions