{"id":71446,"date":"2026-05-20T11:50:00","date_gmt":"2026-05-20T11:50:00","guid":{"rendered":"https:\/\/medsbase.com\/aod-9604\/"},"modified":"2026-05-21T07:14:08","modified_gmt":"2026-05-21T07:14:08","slug":"aod-9604","status":"publish","type":"product","link":"https:\/\/medsbase.com\/nl\/aod-9604\/","title":{"rendered":"AOD-9604 (Anti-Obesity Drug 9604 \/ Tyr-hGH 177-191)"},"content":{"rendered":"

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Quick Answer \u2014 What is AOD-9604?<\/h3>\n

AOD-9604<\/strong> (“Anti-Obesity Drug 9604”, CAS 221231-10-3) is a synthetic 16-amino-acid peptide developed by Metabolic Pharmaceuticals Ltd<\/strong> (Australia) in the late 1990s as a stabilised analogue of the C-terminal lipolytic fragment of human growth hormone. Sequence Tyr-Leu-Arg-Ile-Val-Gln-Cys-Arg-Ser-Val-Glu-Gly-Ser-Cys-Gly-Phe (16 aa, with an N-terminal tyrosine extension that stabilises the parent hGH 177\u2013191 fragment, and a Cys7\u2013Cys14 intramolecular disulfide bridge). Molecular formula C78<\/sub>H123<\/sub>N23<\/sub>O23<\/sub>S2<\/sub>, MW 1815.1 Da. In published in-vitro and rodent research AOD-9604 retains the lipolytic and anti-lipogenic activity<\/strong> of the parent hGH molecule but does niet<\/em> bind the GH receptor \u2014 so it does not induce IGF-1, does not activate growth-axis JAK2\/STAT5 signalling, and does not produce the growth-promoting effects of full-length HGH. Failed Phase IIb obesity trial (2007); now used as a research-grade peptide. For laboratory research use only.<\/em><\/p>\n<\/div>\n

Wat u krijgt bij MedsBase:<\/strong> Lyophilized \u226599% HPLC-verified powder \u00b7 COA available on request \u00b7 Discreet temperature-stable packaging \u00b7 Worldwide research-supply courier \u00b7 1,400+ verified klantbeoordelingen<\/a><\/div>\n

\ud83d\udce6 Elke bestelling is gedekt door onze Reshipment Assurance Policy<\/strong><\/a> \u2014 als uw pakket niet binnen 20 werkdagen arriveert, sturen wij het opnieuw.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Specificatie<\/th>\nDetail<\/th>\n<\/tr>\n<\/thead>\n
Compound Class<\/strong><\/td>\nSynthetic 16-amino-acid peptide; stabilised C-terminal hGH-fragment analogue; lipolytic \/ anti-lipogenic research peptide (decoupled from GH-receptor binding)<\/td>\n<\/tr>\n
Chemical Name<\/strong><\/td>\nAOD-9604 (“Anti-Obesity Drug 9604”; synonyms: Tyr-hGH 177-191; H-Tyr-(177-191 hGH fragment)-OH)<\/td>\n<\/tr>\n
CAS-nummer<\/strong><\/td>\n221231-10-3 (canonical Sigma-Aldrich, MedKoo, ChemicalBook reference)<\/td>\n<\/tr>\n
Molecuulformule<\/strong><\/td>\nC78<\/sub>H123<\/sub>N23<\/sub>O23<\/sub>S2<\/sub><\/td>\n<\/tr>\n
Moleculair gewicht<\/strong><\/td>\n1815.1 g\/mol<\/td>\n<\/tr>\n
Sequentie<\/strong><\/td>\nTyr-Leu-Arg-Ile-Val-Gln-Cys-Arg-Ser-Val-Glu-Gly-Ser-Cys-Gly-Phe (single-letter: YLRIVQCRSVEGSCGF; 16 amino acids). Cys7\u2013Cys14 intramolecular disulfide bridge forms a cyclic structure that mimics the disulfide geometry of the parent hGH 182\u2013189 region. The N-terminal tyrosine is a synthetic addition (not present in native hGH 177\u2013191) that stabilises the fragment against amino-terminal proteolytic degradation.<\/td>\n<\/tr>\n
Werkingsmechanisme<\/strong><\/td>\nMechanistically decoupled lipolysis<\/strong>. AOD-9604 does NOT bind the GH receptor (GHR) \u2014 the GHR-binding surface of native hGH lies in the N-terminal portion (residues 1\u2013120 region), absent from the 176\u2013191 fragment. The lipolytic \/ anti-lipogenic activity is thought to be mediated via \u03b23-adrenergic receptor signalling and direct activation of adipocyte hormone-sensitive lipase (HSL) via cAMP-PKA. The mechanism remains incompletely characterised in published literature \u2014 there is no single confirmed receptor for the C-terminal lipolytic fragment.<\/td>\n<\/tr>\n
Plasma Half-Life<\/strong><\/td>\n~4 minutes (very short \u2014 driven by N-terminal proteolytic truncation despite the stabilising Tyr). This short half-life is one of the leading hypotheses for why the Phase IIb obesity trial (2007) did not achieve weight-loss endpoints \u2014 the fragment is degraded before sufficient receptor exposure can accumulate in target tissue.<\/td>\n<\/tr>\n
Form<\/strong><\/td>\nLyophilized white-to-off-white amorphous powder; single-use research vials<\/td>\n<\/tr>\n
Zuiverheid<\/strong><\/td>\n\u226599% (HPLC verified); MALDI-TOF mass spectrometry confirms 1815.1 Da. COA available on request.<\/td>\n<\/tr>\n
Oplosbaarheid<\/strong><\/td>\nSoluble in bacteriostatic water, sterile water, PBS, and 0.1% acetic acid at \u22655 mg\/mL; readily soluble in DMSO at \u226550 mg\/mL for in-vitro stock preparation. The Cys7\u2013Cys14 disulfide bridge constrains the peptide geometry but does not impede aqueous solubility.<\/td>\n<\/tr>\n
Opslag<\/strong><\/td>\nLyophilized: 2\u20138 \u00b0C unopened for short-term working stock; \u221220 \u00b0C for long-term storage (stable \u226536 months at \u221220 \u00b0C; \u226518 months at 2\u20138 \u00b0C). Reconstituted aqueous: 2\u20138 \u00b0C, use within ~30 days. Protect from light. Avoid repeated freeze\u2013thaw cycles of the reconstituted solution \u2014 the disulfide bridge is stable to single freeze-thaw but cumulative cycles risk free-thiol scrambling and partial aggregation.<\/td>\n<\/tr>\n
Onderzoeksgebruik<\/strong><\/td>\nFor laboratory research use only. Not for human or veterinary diagnostic or therapeutic use. AOD-9604 is not on the current WADA Prohibited List under its specific name, but researchers should be aware that the broader S2 class (Peptide Hormones, Growth Factors, Related Substances and Mimetics) includes growth-hormone fragments and related compounds. AOD-9604 reached Phase IIb obesity trials but did not gain regulatory approval; the Australian TGA at one stage listed AOD-9604 as a permitted ingredient for limited research-context use, with subsequent regulatory clarification varying by jurisdiction.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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What Is AOD-9604?<\/h2>\n

AOD-9604<\/strong> (“Anti-Obesity Drug 9604”; CAS 221231-10-3) is a synthetic 16-amino-acid peptide developed by Metabolic Pharmaceuticals Ltd<\/strong> at Monash University in Melbourne, Australia, beginning in the late 1990s. It is a stabilised analogue of the C-terminal lipolytic fragment of native human growth hormone (residues 177\u2013191), to which an N-terminal tyrosine has been added to slow amino-terminal proteolytic degradation. Sequence Tyr-Leu-Arg-Ile-Val-Gln-Cys-Arg-Ser-Val-Glu-Gly-Ser-Cys-Gly-Phe (YLRIVQCRSVEGSCGF), with the native Cys182\u2013Cys189 intramolecular disulfide bridge of the parent hGH preserved as Cys7\u2013Cys14 within the fragment numbering. Molecular weight 1815.1 g\/mol, empirical formula C78<\/sub>H123<\/sub>N23<\/sub>O23<\/sub>S2<\/sub>.<\/p>\n

The pharmacological logic behind AOD-9604 is one of the cleanest examples of structure-function dissection in HGH peptide research. Native full-length human growth hormone (191 amino acids) has at least two distinct biological activities: growth-promoting \/ anabolic effects<\/strong> (mediated through the GH receptor, JAK2\/STAT5 signalling, and downstream IGF-1 production) and lipolytic \/ anti-lipogenic effects<\/strong> (mediated through a separate, incompletely-characterised mechanism that does not require GH-receptor engagement). The Monash group’s hypothesis was that the lipolytic activity is encoded in the C-terminal region of the molecule \u2014 and that a synthetic peptide encompassing just that region might retain the fat-mobilising activity while losing the growth-axis-engaging activity. This proved correct in published in-vitro and rodent research: the 176\u2013191 fragment retains lipolytic and anti-lipogenic activity in adipocyte culture and DIO mouse models, but does not bind GHR, does not activate JAK2\/STAT5, and does not induce IGF-1.<\/p>\n

AOD-9604 progressed through multiple Phase I and Phase II clinical trials in the early-to-mid 2000s, culminating in a 28-week Phase IIb obesity trial (~500 patients) completed in 2007 by Metabolic Pharmaceuticals. The trial did not achieve its primary weight-loss endpoint, and the obesity-pharmacology development programme was discontinued. AOD-9604 subsequently entered the research-peptide and unregulated-supplement markets, where it has remained one of the most-cited “fat-loss peptides” in non-clinical literature. The compound retains research utility as the canonical pharmacological tool for studying GHR-decoupled lipolysis, the C-terminal hGH fragment biology, and the structure-function basis of HGH’s multiple activities.<\/p>\n

A note on nomenclature: AOD-9604 and “HGH Fragment 176-191<\/a>” are often used interchangeably in the supplier and research-peptide marketplace. Strictly, AOD-9604 (CAS 221231-10-3) is the Metabolic-Pharmaceuticals-developed analogue with the N-terminal Tyr stabilisation. “HGH Fragment 176-191” (CAS 66004-57-7 per some references) is the older, un-stabilised hGH 177\u2013191 fragment that AOD-9604 was derived from. Both share the same YLRIVQCRSVEGSCGF amino-acid sequence in many supplier preparations \u2014 but the AOD-9604 designation specifically identifies the registered Metabolic-Pharmaceuticals research compound. Researchers should consult the COA to confirm which form a given supplier batch corresponds to.<\/p>\n

Mechanism of Action \u2014 GHR-Decoupled Lipolysis<\/h2>\n

AOD-9604’s mechanism is among the most-discussed in HGH peptide research:<\/p>\n