GH-Derived Lipolytic Peptide Class / hGH Fragment Research Compounds
Fat-Loss Peptides Research — AOD-9604 & HGH Fragment 176-191
AOD-9604 and HGH Fragment 176-191 are two closely related growth-hormone-derived peptides studied for lipolytic activity in preclinical models. Both are truncated C-terminal fragments of human growth hormone (hGH), specifically the region responsible for hGH's lipolytic effects — distinct from the N-terminal domain that mediates IGF-1 secretion and anabolic signaling. AOD-9604 (anti-obesity drug 9604; CAS 221231-10-3; MW ~2036 Da) is a stabilized fragment comprising hGH residues 177–191 with a Tyr modification at the N-terminus. HGH Fragment 176-191 (CAS 66004-57-7; MW ~1815 Da) refers to residues 176–191 of hGH. Both have been studied in adipogenesis, lipolysis, and metabolic models; AOD-9604 completed Phase I/II clinical trials before development was paused. This hub covers both compounds, their differences, and research contexts. Research use only.
Compound identity
- Name
- Fat-Loss Peptides — AOD-9604 & HGH Fragment 176-191 Research Hub
- Class
- GH-Derived Lipolytic Peptide Class / hGH Fragment Research Compounds
- Also known as
- fat loss peptide, weight loss peptide research, AOD-9604 research, HGH fragment 176-191 research, AOD 9604 vs HGH fragment, hGH fat loss fragment, lipolytic peptide, peptide for fat loss research, AOD-9604 HGH fragment comparison, anti-obesity peptide research, growth hormone fat loss fragment, AOD9604
Research context
The mechanistic rationale for hGH fragment lipolytic activity originates from structure-activity studies of growth hormone in the 1980s–1990s: researchers observed that the C-terminal region of hGH (approximately residues 176–191) stimulates lipolysis in adipocytes at concentrations far lower than those required for the full-length hormone, without measurable IGF-1 stimulation. This selectivity made it an attractive research target — a compound that might mobilize fat stores without the anabolic/proliferative and hyperglycemic effects associated with full-length GH administration. AOD-9604 was developed by Metabolic Pharmaceuticals (Australia) to advance this fragment into clinical evaluation; it added a tyrosine residue at the N-terminus for improved metabolic stability. HGH Fragment 176-191 is the corresponding unmodified natural-sequence fragment and is more commonly referenced in academic literature.
AOD-9604 has the most substantial clinical trial record of the two. Phase I trials demonstrated safety and tolerability; Phase IIa/IIb trials in overweight and obese subjects examined effects on body weight, adipose mass, and metabolic markers over 12–24 weeks. Results from the Phase II program showed modest but statistically significant reductions in body fat in some subgroups. Development was paused before Phase III, and the compound does not hold regulatory approval as a therapeutic agent. In vitro studies with both AOD-9604 and HGH Fragment 176-191 have examined adipocyte lipolysis rates, chondrocyte function — an unexpected finding from the AOD-9604 clinical program — and bone/cartilage metabolism, making these compounds of interest beyond purely metabolic models.
For researchers comparing AOD-9604 and HGH Fragment 176-191: the primary distinction is the N-terminal Tyr modification (present in AOD-9604, absent in HGH Frag 176-191), which affects the peptide's half-life in aqueous solution and binding characteristics. Functionally, both compounds bind the same putative receptor region and produce similar lipolytic readouts in adipocyte models. AOD-9604 provides a richer clinical trial dataset (published Phase II data is available); HGH Fragment 176-191 is more commonly cited in mechanistic biochemistry papers. Neither compound has been approved for any therapeutic use. DMV Research supplies both as research-grade lyophilized peptides with ≥99% purity by HPLC and full COA.
Frequently asked questions
What is the difference between AOD-9604 and HGH Fragment 176-191?+
AOD-9604 (CAS 221231-10-3, MW ~2036 Da) is hGH residues 177–191 with an additional N-terminal Tyr residue for stabilization. HGH Fragment 176-191 (CAS 66004-57-7, MW ~1815 Da) is the natural-sequence fragment of hGH residues 176–191. Both produce similar lipolytic effects in adipocyte models; AOD-9604 has more clinical trial data (Phase II completed). Research use only.
How does the hGH fat-loss fragment work mechanistically?+
The C-terminal region of human growth hormone (approximately residues 176–191) stimulates lipolysis in adipocytes through a mechanism that does not require IGF-1 secretion or the anabolic effects of full-length GH. In-vitro studies suggest it activates lipase activity in adipocytes, increasing free fatty acid release. It does not appear to significantly stimulate the growth hormone receptor's anabolic signaling pathway. Research use only; no approved therapeutic claim.
What is AOD-9604's research history?+
AOD-9604 was developed by Metabolic Pharmaceuticals (Australia) and completed Phase I safety trials and Phase IIa/IIb efficacy trials in overweight and obese subjects. Phase II data showed modest but statistically significant reductions in body fat in some subgroups. Development was halted before Phase III; no regulatory approval exists for any therapeutic use. All current research references historical clinical data or preclinical models.
Can fat-loss peptides be combined with other peptides in research?+
In research protocols, AOD-9604 and HGH Fragment 176-191 have been studied alongside other metabolic peptides including GLP-1 analogs and GHRPs in animal models. Any combination research is strictly in-vitro or animal-model work. These are research compounds only — not approved for human use, not for human consumption, research use only.
Research use only
All products are intended for laboratory and research use only (RUO) and are not for human consumption, ingestion, or any in-vivo use.
The statements on this page have not been evaluated by the FDA. Fat-Loss Peptides — AOD-9604 & HGH Fragment 176-191 Research Hub is not intended to diagnose, treat, cure, or prevent any disease. Content is provided for laboratory research reference only.