In vitro activity: GW9508 is shown to be at least 100-fold selective against 220 other GPCRs, 60 kinases, 63 proteases, seven integrins and 20 nuclear receptors including PPARα, δ and γ (pEC50 4.0, 4 and 4.9, respectively). GW9508 produces a concentration-dependent increase in intracellular Ca2+ concentrations via GPR40 receptor activation and the GPR120 receptor. GW9508 is active as an agonist at both GPR40 and GPR120, it is approximately 100-fold selective for GPR40 with respect to GPR120. GW9508 produces a concentration-dependent increase (pEC50=6.14) in glucose-stimulated insulin secretion at high glucose levels (25 mM). GW9508 dose dependently stimulated insulin secretion in a glucose-sensitive manner in MIN6 cells. Furthermore, GW9508 is able to potentiate the KCl-mediated increase in insulin secretion in MIN6 cells. GW9508 induced hyperpolarization and opening of KATP channels in rat β-cells. GW9508 inhibits CCL17 and CCL5 expression in a pertussis toxin-sensitive manner. GW9508 further suppresses expression of IL-11, IL-24, and IL-33 induced in HaCaT cells by TNF-α and IFN-γ. GW9508 also inhibits CCL5 and CXCL10 production by normal human epidermal keratinocytes.

Cell Assay: When tested with HEK-293 (human embryonic kidney) cells expressing GPR40 or GRP120, GW9508 treatment increased intracellular Ca2+ concentration via activating GPR40/120 in a dose-dependent manner. In rat pancreaticβ-cells, GW9508 treatment activated KATP channels which inhibited GSIS through agonist of GPR40 and GPR120. When tested with TNF-α treated rat L cells, administration of GW9508 increased the expression of GLP-2 via activating GPR40 and 120.