AOD-9604 was originally developed as an analogue of HGH with the express purpose of fighting fat. Phase 2b clinical trials were completed in Australia testing the drug in 300 obese individuals. The results of once daily administration of the peptide for 12 weeks showed that the drug tripled weight loss when compared to placebo and that the rate of weight loss remained steady during the trial period.
This latter fact indicates that a resistance to the peptide is unlikely to arise and that longer-term treatment would result in even greater weight loss.
Research in mice that are genetically prone to obesity indicates that AOD-9604 most likely does not work only by affecting the beta-3-adrenergic receptors found on white fat. It was originally speculated that the peptide bound to these receptors and increased the rate of metabolism in fat cells, shifting them from a storage mode to a usage mode. It turns out that even in mice that lack these receptors, fat loss takes place when AOD-9604 is administered.