AOD-9604 (Anti-Obesity Drug 9604) is a synthetic peptide fragment corresponding to amino acids 176-191 of the C-terminus of human growth hormone (hGH), with an additional tyrosine residue at the N-terminus. The modification strategy behind AOD-9604 was deliberate: retain the lipolytic properties attributed to the C-terminal region of hGH while eliminating IGF-1 stimulation and proliferative effects associated with the full-length hormone.
Molecular Design Strategy
Full-length human growth hormone exerts its anabolic and metabolic effects through binding to the GH receptor, triggering downstream IGF-1 production and a range of proliferative effects. Researchers studying isolated metabolic effects of hGH required a tool that could dissociate these effects.
AOD-9604's structure prevents GH receptor binding while preserving activity at fat cell receptors relevant to lipolysis research. This selectivity makes it a useful tool for studying metabolic mechanisms in isolation from the proliferative GH axis.
Preclinical Research Findings
Studies in obese animal models have investigated AOD-9604's effects on body composition, with researchers observing:
These findings confirmed the design hypothesis: the C-terminal fragment retains metabolic activity with a substantially altered safety profile relative to full-length hGH in preclinical models.
Regulatory History
AOD-9604 has an interesting regulatory history — it was investigated as a pharmaceutical by Metabolic Pharmaceuticals and reached Phase III clinical trials for obesity treatment. The clinical programme did not demonstrate sufficient efficacy for regulatory approval, though the compound remains of significant interest to researchers studying adipocyte biology and metabolic signalling.
Research Considerations
AOD-9604 has a molecular weight of 1,817 Da and a relatively short peptide sequence, making it amenable to solid-phase peptide synthesis with high purity. Researchers should source lyophilised preparations with HPLC and MS documentation confirming ≥99% purity.
For in vitro research use only.