The Peptide Atlas
AOD-9604
A synthetic copy of the tail end of the growth hormone molecule (amino acids 177-191), the region tied to fat metabolism.
Class
Growth hormone fragment (177-191)
Evidence
Early research
Status
Studied in research settings.
Forms
Studied as injection; sold in the gray market as injection and oral
What people use it for
Fat loss, by people drawn to the idea of growth hormone's fat effect without the rest.
The signal
Growth hormone affects fat and muscle through different parts of its structure. AOD-9604 isolates the fat-metabolism region, the idea being the fat effect without the rest of growth hormone's actions.
How it works
In lab studies the fragment reduces fat creation and increases fat breakdown, without raising IGF-1 or affecting blood sugar the way full growth hormone does [1].
What the research shows
This is the category's clearest example of a gap between corporate history and published science. A pharmaceutical company ran human obesity trials on it in the early 2000s; our search found no published efficacy results from that program, and recent reviews of unapproved peptides reach the same conclusion [2]. What's citable is the mechanism work, and the fact that the development program ended without bringing it to market.
What people get wrong
That "it went through human trials" means it worked. Trials ran; results never appeared in the literature, and the program stopped. Unpublished trials are usually not good news, and treating them as evidence gets the logic backwards.
References
- Ng FM, Bornstein J. Biochem Mol Biol Int (1993). Antilipogenic action of synthetic C-terminal sequence 177-191 of human growth hormone. PubMed
- Sports Med (2026). Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries. PubMed
Last reviewed 2026-08-24. Every reference is verified against the primary literature at review time. How the Atlas grades evidence