Bydureon is a new galenic formulation (long-acting release) of exenatide, the first agonist of Glucagon-Like Peptide-1 (GLP-1) receptors having been commercialized for the management of type 2 diabetes. The microsphere technology permits a prolonged absorption of exenatide from the subcutaneous depot, which allows one injection per week instead of two injections per day with the initial formulation of exenatide (Byetta). The clinical development programme DURATION showed that exenatide 2 mg once weekly more markedly reduces glycated haemoglobin (HbA(1c)), with a similar weight loss but a better digestive tolerance profile (less nausea and vomiting after treatment initiation), compared with the twice daily 10 microg exenatide. When compared to other glucose-lowering agents, once weekly exenatide is more efficacious than sitagliptin, pioglitazone or basal insulin (glargine or detemir), with the advantage of producing weight loss and lowering arterial blood pressure. It does not induce hypoglycaemia and does not necessarily require home blood glucose monitoring, two advantages compared with insulin therapy. Bydureon is currently only reimbursed in Belgium after failure of and in addition to metformin-sulfonylurea combination.