AOD-9604

AOD-9604 (also written AOD9604 or AOD 9604) is a synthetic peptide modeled on the C-terminal region of human growth hormone (hGH). PubChem records a 16-residue sequence, YLRIVQCRSVEGSCGF, closed by a disulfide bond between its two cysteines (CID 71300630). Analytical work describes the molecule as the hGH 177-191 fragment with an extra tyrosine at the N-terminus (Cox et al., 2015), while the Monash University group that developed the series worked on the same parent sequence and on a closely related analog, AOD9401 (Ng et al., 2000).

The published record is mostly cell-culture and rodent work from the 1990s and early 2000s, plus later analytical chemistry papers.

AOD-9604 was carried into clinical development as an investigational obesity candidate, with phase IIa trials under way by February 2002 (Wilding, 2004), and it was listed among compounds then in development (Halford, 2006). Our material is research-grade powder, not a drug product, and not for people.

Published work on AOD-9604 falls into five areas. Each summary below states the model used.

Structure and identity

Two-dimensional NMR of the cyclic parent peptide found type I beta-turns in the cyclic region, and the authors reported that the synthetic peptide keeps some structural similarity to the corresponding region of the intact hGH crystal structure (Ogru et al., 2000). Mass spectrometry later characterized AOD9604 in seized pharmaceutical preparations (Vanhee et al., 2014).

Adipose tissue in cell and tissue models

Early work on the synthetic hGH 177-191 sequence reported antilipogenic activity in rat fat pads comparable to intact hGH, with no significant change in glycerol release (Wu and Ng, 1993). In adipocytes from genetically obese Zucker rats, the same peptide reduced basal and insulin-stimulated deoxyglucose uptake and was more potent than intact hGH at equimolar concentrations (Wijaya and Ng, 1993). A later study of the related fragment AOD-9401 (hGH 177-191) reported increased lipolytic and decreased lipogenic activity in isolated adipose tissue from obese rodents and from humans (Heffernan et al., 2000).

Rodent models of obesity

In obese Zucker rats, 19 days of an oral regimen at 500 micrograms per kilogram reduced body weight gain by over 50 percent against control, raised lipolytic activity in adipose tissue, and, unlike intact hGH, showed no adverse effect on insulin sensitivity measured by euglycemic clamp (Ng et al., 2000).

In ob/ob mice given AOD-9401 on a 30-day oral regimen, body weight gain diverged from saline controls from day 16 onward with no difference in food consumption (Heffernan et al., 2000). A 14-day pump study in obese and lean mice reported increased fat oxidation and plasma glycerol, and reported that the peptide neither competed for the hGH receptor nor induced proliferation through it in transfected cells (Heffernan et al., 2001).

Beta-3 adrenergic receptor experiments

In obese mice and beta-3 adrenergic receptor knockout mice, 14 days of hGH or AOD9604 raised beta-3 receptor mRNA, but the weight and lipolysis changes seen in wild-type animals did not occur in the knockouts, which the authors read as evidence that the lipolytic actions are not mediated directly through that receptor (Heffernan et al., 2001).

Analytical detection and stability

Anti-doping laboratories have characterized the peptide because it circulates in unregulated supply. A validated urine method reached a detection limit of 50 picograms per milliliter, and incubation in serum and urine produced six candidate metabolites, of which the fragment CRSVEGSCG was markedly more stable than the parent (Cox et al., 2015).

A separate laboratory reported no interference with the hGH isoform immunoassay (Orlovius et al., 2013). A 2026 method study found the peptide extensively degraded after one week in serum and plasma at 4 and 22 degrees Celsius, while holding up for at least two months at -20 degrees Celsius and in dried matrices (Mazzarino et al., 2026).