At a glance
| Family | Growth-hormone C-terminal fragments |
|---|---|
| Critical issue | Exact sequence and modification |
| Nearby research molecule | hGH 177–191 |
| Distinct modified analog | AOD-9604 |
| Clinical evidence | No established human fat-loss use |
Overview
A native amino-acid fragment, a modified analog and a supplier’s trade label are different forms of identification. The older literature studied hGH 177–191, while AOD-9604 has an additional N-terminal tyrosine. Products advertised as Fragment 176–191 are frequently discussed using those neighboring compounds’ evidence. This profile remains separate from AOD-9604 so that uncertainty is visible instead of silently merging unlike identities. There is no established clinical obesity treatment defined solely by the phrase 'HGH fragment.' Exact sequence, modification, purity and the actual studied material are prerequisites for a valid evidence comparison.
How it works
Research on C-terminal growth-hormone sequences explored whether effects on lipid synthesis could be separated from the full hormone’s growth-promoting actions. A study of hGH 177–191 found an antilipogenic effect in rats but did not find significant stimulation of lipolysis under its test conditions. That distinction matters: less synthesis of fat is not the same mechanism as increased breakdown, and neither automatically establishes human weight reduction.
Why the names are not automatically aliases
The analytical literature defines AOD-9604 as hGH residues 177–191 with added tyrosine. That is a specific modified molecule. A reference to native residues or a nonspecific fragment label does not by itself prove the same identity.
Supporting sources [1]
What the original fragment experiment measured
The 1993 study examined a synthetic 177–191 sequence in rats. It reported inhibition of lipid synthesis but no significant lipolytic effect by its glycerol-release measurement. It was neither a human obesity trial nor direct proof for every 176–191 product.
Supporting sources [2]
Can AOD-9604 results be borrowed?
Only with explicit identification of the molecule and an appropriate scientific rationale. Moreover, AOD-9604’s larger obesity trial failed to show significant benefit over placebo, so borrowing its evidence would not establish a proven human weight-loss treatment anyway.
What is not established
A fragment lacking selected intact-GH activities is not automatically harmless. Route-specific human exposure, endocrine effects, immune responses and long-term toxicity remain insufficiently characterized for products sold under this broad label.
How to interpret a vendor description
A claim that the product contains the 'fat-burning part' of growth hormone compresses identity, mechanism and clinical efficacy into one unsupported conclusion. The knowledge record keeps those questions separate and does not infer an approved indication from a sequence nickname.
Reading this profile
Jurisdiction: Research-only identity-sensitive entry; no FDA-approved Fragment 176–191 medicine identified.. Molecular class: C-terminal growth-hormone fragment; product identity requires verification.
This profile was written with AI-assisted research and checked against the linked sources. It has not been represented as a clinician’s review. Evidence summaries describe the cited studies and products; they do not establish that a separately purchased preparation is equivalent.
Sources & references
Follow the original material. Product labels define specific formulations and uses; trial registration describes a study and does not by itself establish benefit.
- Detection and in vitro metabolism of AOD9604: sequence identity ↗Original research · Checked 2026-10-27
- Antilipogenic action of synthetic C-terminal sequence 177–191 of human growth hormone ↗Original research · Checked 2026-10-27
- FDA December 2024 review of AOD-9604 efficacy and safety ↗Regulatory source · Checked 2026-10-27