AP5 is a potent and selective agonist for the GPR40 receptor with positive allosteric modulation of endogenous ligands (AgoPAM). AP5 demonstrates a rat hIP1 EC50 of 0.49 nM against the GPR40 receptor.

FFA1/GPR40 receptor:（EC50）0.49±0.28 nM

In the GK rat oral glucose tolerance test (oGTT), oral administration of AP5 1 h before an oral dextrose challenge shows that AP5 significantly reduces blood glucose levels compared to the vehicle. AP5 is determined to be more efficacious in this model, demonstrating maximally efficacious glucose-lowering at a plasma concentration of 4.9 μM at 10 mg/kg.