In vitro activity: TAK-875 (also known as Fasiglifam) is a novel, potent, selective and orally bioavailable and selective GPR40 agonist with EC50 of 14 nM in human GPR40 expressing CHO cell line, it is 400-fold more potent than oleic acid. TAK-875 has a favorable pharmacokinetic profile which enables long-acting drug efficacy. TAK-875 exhibited potent agonistic activity and high binding affinity to the human GPR40 receptor. In addition, TAK-875 showed excellent agonist potency and selectivity for GPR40 receptor over other members of the FFA receptor family (e.g. EC50>10 μM for others). TAK-875 exhibits potent agonist activity and high binding affinity to the human GPR40 receptor with Ki of 38 nM. TAK-875 displays weaker affinity toward the rat GPR40 receptor with Ki of 140 nM. TAK-875 displays excellent selectivity, as TAK-875 has little agonist potency to other members of the FFA receptor family with EC50 of>10 μM. TAK-875 treatment induces a concentration-dependent increase in intracellular IP production in CHO-hGPR40 with EC50 of 72 nM, more potently than that of endogenous ligand agonist oleic acid which requires much higher ligand concentrations to activate the receptor with EC50 of 29.9 μM. Neither TAK-875 nor oleic acid elicits an IP response in control CHO cells devoid of hGPR40. Consistent with the activation of the Gqα-mediated signaling pathway, TAK-875 augments glucose-dependent insulin secretion in pancreatic β cells. Prolonged stimulation of GPR40/FFA1 by TAK-875 does not cause pancreatic β Cell dysfunction or induction of apoptosis.

Kinase Assay: TAK-875 (also known as Fasiglifam) is a novel, potent, selective and orally bioavailable and selective GPR40 agonist with EC50 of 14 nM in human GPR40 expressing CHO cell line, it is 400-fold more potent than oleic acid.

Cell Assay: INS-1 832/13 cells are suspended in RPMI medium containing 11 mM glucose and the supplements described above. These cells are seeded at a density of 2×104 cells/well in a 96-well black plate coated with poly-D-lysine, and 1% BSA and 0.1% DMSO alone (control), palmitic acid (62.5, 125, 250, 500, and 1000 μM), oleic acid (62.5, 125, 250, 500, and 1000 μM), or TAK-875 (6.25, 12.5, 25, 50, and 100 μM) is added to the plate with 1% BSA and 0.1% DMSO, followed by culture for 72 h. After the culture, caspase 3/7 activity is measured with the Apo-one homogeneous caspase 3/7 assay according to the manufacturer's instructions. Fluorescence intensity is measured at an excitation of 485 nm and an emission at 535 nm