Treatment of type 2 diabetes with glucagon-like peptide-1 receptor agonists

The incretin system is an area of great interest for the development of new therapies for the management of type 2 diabetes. Existing antidiabetic drugs are often insufficient at getting patients to glycaemic goals. Furthermore, current treatment modalities are not able to prevent the continued ongoing decline in pancreatic beta-cell function and, lastly, they have a number of side effects including hypoglycaemia and weight gain. Glucagon-like peptide-1 (GLP-1) receptor agonists are a new class of pharmacological agents, which improve glucose homeostasis in a multifaceted way. Their effects include potentiation of glucose-stimulated insulin secretion, glucose-dependent inhibition of glucagon secretion and reduction in gastric emptying, appetite, food intake and body weight. Additionally, preclinical data suggest that they may preserve beta-cell mass and function. The incidence of hypoglycaemia with GLP-1 receptor agonists is low, the compounds have clinically relevant effects on body weight, and data are suggesting beneficial effects on cardiovascular risk factors. Exenatide was released in 2005 for the treatment of type 2 diabetes and liraglutide is expected to be approved by the Food and Drug Administration in US and the European Medical Agency in Europe for use in 2009. In this review, the available data on the two drugs are presented and discussed.