Compound 51 (Amgen)

Compound 51 is a potent, small-molecule agonist of the **Free Fatty Acid Receptor 1 (FFAR1)**, also known as **GPR40**, developed by **Amgen** for the potential treatment of **type 2 diabetes mellitus**. FFAR1 is a G protein-coupled receptor primarily expressed in pancreatic beta-cells that plays a crucial role in modulating insulin secretion. Compound 51 acts by enhancing glucose-stimulated insulin secretion (GSIS), meaning it promotes insulin release only when blood glucose levels are elevated. This glucose-dependent mechanism of action is therapeutically desirable as it significantly reduces the risk of hypoglycemia compared to other insulin secretagogues like sulfonylureas. Although it showed high potency and efficacy in preclinical models, Compound 51 was primarily utilized as a key lead compound in the discovery and optimization of Amgen's GPR40 agonist pipeline, which included candidates like AMG 837 and AM-1638.