AOD-9604 stimulates lipolysis and inhibits lipogenesis through mechanisms believed to be independent of the insulin-like growth factor pathway. It appears to mimic the fat-metabolising action of growth hormone without triggering the proliferative effects associated with full GH or GH-releasing peptides. Oral bioavailability has been observed in some formulations, making it of interest for non-injectable protocols.

Tesamorelin stimulates pulsatile GH secretion from the anterior pituitary by binding GHRH receptors. Its stabilisation protects it from rapid enzymatic cleavage by dipeptidyl peptidase IV, extending the effective half-life compared to unmodified GHRH. Downstream effects on visceral adiposity are mediated through elevated IGF-1 and direct lipolytic signalling.