THE READING KEY
Five peptides, five naming systems, one reading key
What each name encodes, what it conceals, and how far the evidence behind each compound actually reaches.
The short version
Peptide names come from four or five different systems that were never designed to work together. This page sets them side by side.
The useful idea is that names arrive in a rough order. A compound picks up a company code first, while it is still a research programme. If it advances far enough through regulatory review, it is given a generic name built from standard word-parts. If it reaches market it also gets a trademark. Along the way it may collect a descriptive acronym from the lab that studied it, a chemical description written in the notation of the field, and an informal nickname from whoever talks about it most.
So a name is a rough position report. A compound still going by its code has usually not finished the path that produces generic names — and that path is also the one that produces dossiers, labels and monitoring. That is why reading the register first is worth the effort: it estimates how much scrutiny a compound has been through before a single study is opened.
The five names, decoded
| Compound | Naming register | What the name itself encodes | Where the evidence stands |
|---|---|---|---|
| Semaglutide | Generic name, plus three trademarks: Ozempic, Wegovy, Rybelsus | -tide = peptide; -glutide = GLP-1 analogue family. The trademarks encode nothing | Approved; multiple large outcome trials [3][4][2] |
| Tirzepatide | Generic name; marketed under trademarks this site does not name | -tide = peptide; the absence of -glutide = not simply a GLP-1 analogue | Approved; large trials incl. head-to-head [10][1][11] |
| CJC-1295 | Company development code | Letters = originating organisation; digits = compound number. Encodes nothing pharmacological | Not approved; a handful of early human pharmacology studies [15][16][14] |
| BPC-157 | Descriptive laboratory acronym | Body Protection Compound — asserts a function; the numeral's meaning is unrecorded | Not approved; extensive rodent work, three human pilot studies [18][21][17] |
| PT-141 | Research code, generic name bremelanotide, trademark Vyleesi — all three registers at once | The code encodes nothing; the generic name encodes -tide = peptide and melano = melanocortin system | Approved as bremelanotide for one indication; phase 3 trials [24][25] |
Read down the last two columns together. The two compounds whose names are generic names are the two with the largest and most scrutinised evidence bases. The two whose names are codes or acronyms are the two that are not approved anywhere. Note also which compounds carry trademarks at all: only the approved ones do, because a trademark is attached to a marketed product, and the unapproved compounds have no product to market. The presence of a brand name is thus itself a rough approval signal — though never a quality one, since it reports only that something reached a shelf. PT-141 is the instructive middle case: the molecule completed the path and earned a generic name, but a parallel supply chain kept using the old code, and the code now travels with material that has none of the approved product's guarantees.
How the mechanisms differ
The five compounds have almost nothing pharmacological in common, which is precisely why they work as naming specimens — the naming patterns hold across completely unrelated biology.
| Compound | Length | Acts on | Where it acts |
|---|---|---|---|
| Semaglutide | 31 amino acids | GLP-1 receptor | Pancreas, hypothalamus, brainstem, stomach |
| Tirzepatide | 39 amino acids | GIP receptor and GLP-1 receptor | Same axis, two receptor arms |
| CJC-1295 | 29-residue GHRH fragment, four substitutions | GHRH receptor | Anterior pituitary, then the growth hormone/IGF-1 axis |
| BPC-157 | 15 amino acids | VEGFR2 and the nitric-oxide system | Injured tissue; angiogenesis |
| PT-141 | 7 amino acids (cyclic) | MC4R, and MC3R | Hypothalamus and limbic system |
Two of these lengths are recoverable from names. Pentadecapeptide BPC 157 states fifteen in Greek, and the sequence confirms it. Cyclic heptapeptide states seven for PT-141. The notation hGRF(1-29) states which fragment of the parent hormone CJC-1295 is built from. Greek numeral prefixes and residue-range parentheticals are among the few naming elements that make a claim a reader can check by counting.
How the evidence maturity differs
Evidence maturity varies across these five by orders of magnitude, and lumping them together as research peptides obscures that completely.
At one end, semaglutide has been tested for cardiovascular outcomes in 17,604 participants [3], for kidney outcomes in 3,533 [2], and for weight in 1,961 [4]. Tirzepatide has a 2,539-participant weight trial [10], an 1,879-participant glycaemic trial [11], and a 751-participant head-to-head comparison [1], plus a pooled safety analysis across 9,871 participants [9].
At the other end, BPC-157 had, as of 2025 reviews, three small human pilot studies — one of which enrolled two people [17][18]. CJC-1295's human record consists of early pharmacology studies measuring hormone levels in healthy volunteers, in groups of roughly a dozen [14][15][16]; those establish that the compound raises growth hormone and IGF-1 as designed, and nothing about whether that produces a benefit.
PT-141 sits in between and slightly apart: two identical phase 3 trials totalling 1,267 participants met their endpoints [24], a 52-week extension followed 684 [25] — and critical re-analyses argue the effects, while statistically significant, are small enough that their clinical meaningfulness is debatable. A mature evidence base is not the same thing as a large effect, and the naming system does not distinguish the two.
The reading key
Applied to any peptide name encountered anywhere, these are the patterns this hub's five specimens demonstrate.
- Ends in
-tide→ a peptide that has been assigned a generic name, which normally means it progressed far enough through regulatory review to be given one. - Ends in a longer stem such as
-glutide→ membership of a specific receptor family. The stem is a compression scheme, so a stem that stops short is itself informative, as on the tirzepatide page. - Contains a decodable root such as
melano→ the receptor system, embedded in the middle of the word rather than at the end. - Letters followed by digits (LY3298176, NNC0113-0217, CJC-1295, PL 14736) → a company or laboratory development code. It encodes no pharmacology and, standing alone as the primary name, usually means no generic name was ever assigned.
- An acronym that expands into a phrase (BPC = Body Protection Compound) → a descriptive laboratory name. Worth expanding, because it may be making a claim.
- A Greek numeral prefix (pentadeca-, hepta-) → a residue count, and a checkable one.
- A parenthetical range (hGRF(1-29), alpha-MSH(4-10)) → which fragment of a parent molecule is in play.
- A class phrase (GLP-1 receptor agonist, melanocortin receptor agonist) → a target, not a molecule. Several compounds satisfy each.
- A suffix modifier (DAC / no-DAC) → a formulation difference, which may be pharmacologically enormous while looking trivial in text. This is the failure mode documented on the CJC-1295 page.
- A memorable coinage (twincretin) → informal, with no standing in any nomenclature system.
- A trademark (Ozempic, Wegovy, Rybelsus, Vyleesi) → a marketed product: one formulation, at set strengths, for set indications. Trademarks are owned, jurisdiction-bound, and can be plural for a single molecule — semaglutide carries three. A trademark therefore says a great deal about a commercial offering and almost nothing about chemistry, which is why the generic name is the one worth indexing on.
One caution outranks the rest: a correct name on a label guarantees nothing about the contents of a vial. Regulators documented unverified active ingredients in compounded semaglutide during a shortage, mass spectrometry was required to establish what a preparation labelled only GHRH actually contained [13], and forensic testing confirms unregulated melanocortin product circulates. Names describe molecules. They do not authenticate products.