KDC-MN-085 – Kodiac biolabs

Plain-language summaryIntrigue 55 / 100

AOD-9604 is a modified fragment of the C-terminal portion of human growth hormone (residues 176-191). It was developed by Metabolic Pharmaceuticals as a fat-loss agent that retains the lipolytic effects of GH without the muscle-building effects. Not stocked by Kodiac. This monograph is provided for research and educational reference.

Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

Our opinion on this compoundOverhyped vs evidence

37/100

Failed phase 2 lipolysis candidate with modest human signal and no clear research frontier

Look, the concept behind AOD-9604 is genuinely interesting: take the C-terminal region of hGH (residues 176-191), add a tyrosine at the N-terminus, and you theoretically get the lipolytic activity of growth hormone without the IGF-1-mediated growth effects, the diabetogenic risk, or the need to suppress endogenous GH secretion. That’s a clean hypothesis. The problem is that the clinical data didn’t back it up at the level you’d need.

The Metabolic Pharmaceuticals phase 2 work showed modest weight loss and fat mass reduction in obese subjects. “Modest” is doing a lot of heavy lifting in that sentence. The compound didn’t advance because regulators and the company agreed the efficacy signal wasn’t sufficient for a marketed obesity drug. That’s not a story of a mechanism being disproven. The lipolytic activity appears real. But it is a story of a mechanism that, when translated to humans at tolerable doses, produces underwhelming effect sizes.

That historical context matters a lot right now. The fat loss peptide landscape in 2025-2026 is absolutely dominated by the GLP-1 and dual/triple incretin story. Semaglutide delivers 10-15% body weight loss in clinical practice. Tirzepatide is hitting 20%+. Retatrutide is pushing even further. Against that backdrop, “modest fat mass reduction” from a subcutaneous peptide with a plasma half-life under an hour looks very hard to justify as a primary research target. You’re working in a therapeutically crowded space where the competition has completed phase 3 trials.

What we think still has value here is the probe angle. If your research question is specifically about the structure-activity relationships of hGH C-terminal fragments, the separation of the lipolytic versus somatotropic domains, or beta-3 adrenergic receptor involvement in hGH-driven lipolysis, AOD-9604 is a legitimate tool. Thats a narrow use case, but its a real one. The short half-life is honestly a research complication more than a feature; you’re dealing with rapid clearance that makes sustained exposure studies difficult unless you’re designing specific dosing regimens around it.

The sourcing situation is standard peptide research chemical territory: multiple vendors, variable QC, standard lyophilized powder reconstitution. Nothing remarkable there. The compound doesnt have the replication problem of something like BPC-157: there are real human trials to point to, but those trials tell a story of limited clinical utility, not hidden potential. For a bench scientist trying to choose where to spend time in metabolic biology, AOD-9604 sits well below the frontier.

Novelty: 28
Mechanism promise: 40
In-category differentiation: 30
Evidence quality: 48
Translational signal: 38
Research bench value: 40

Rationale AOD-9604 had a coherent mechanistic hypothesis and real phase 2 clinical data, but failed to achieve regulatory-level efficacy; in a landscape now dominated by GLP-1 and multi-incretin compounds, its modest fat mass signal offers little competitive rationale for primary research focus, though narrow probe utility for hGH fragment biology remains.

Modified hGH 176-191 fragment

A modified C-terminal fragment of hGH (residues 176-191) developed for fat loss without GH metabolic effects.

Abstract

AOD-9604 (modified hGH 177-191; molecular formula C78H125N23O23S2) is a modified analog of the C-terminal fragment of human growth hormone (residues 176-191) developed by Monash University and Metabolic Pharmaceuticals. The structural modification is the addition of a tyrosine at the N-terminus relative to the unmodified 176-191 sequence. The compound was developed on the rationale that the lipolytic activity of human growth hormone resides in the C-terminal fragment, separable from the IGF-1-mediated growth-promoting and pro-diabetogenic activities. Phase 2 trials in obesity showed modest weight loss and fat mass reduction without effect on lean mass or insulin sensitivity. The compound did not advance to FDA approval; clinical efficacy was not strong enough to support marketing. The compound is sold as a research chemical/peptide. Pharmacokinetics: plasma half-life of subcutaneous AOD-9604 is short (less than 1 hour); reported doses for research-grade lipolysis applications are 250 to 500 micrograms subcutaneously daily.

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The full reference document covers compound identification, discovery and developmental history, mechanism of action, pharmacokinetics, sourcing and quality verification, and a curated reference list. Embedded inline below; download for offline reading.

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FOR RESEARCH USE ONLY. Not for medical, diagnostic, or therapeutic purposes. Not for human consumption. All information is provided for research and educational purposes only.

Tag: KDC-MN-085

AOD-9604

Abstract

Read the full monograph