The selective once-daily prandial glucagon-like peptide-1 (GLP-1) receptor agonist lixisenatide (Lyxumia(®)) is under development with Sanofi for the treatment of type 2 diabetes mellitus. Lixisenatide belongs to a class of GLP-1 compounds designed to mimic the endogenous hormone GLP-1. Native GLP-1 stimulates insulin secretion in a glucose-dependent manner, as well as suppressing glucagon production and slowing gastric emptying. A once-daily subcutaneous formulation of lixisenatide has been approved in the EU, Iceland, Liechtenstein, Norway and Mexico for the treatment of type 2 diabetes, and is under regulatory review in the USA, Switzerland, Brazil, Canada, Ukraine, South Africa, Japan and Australia. This article summarizes the milestones in the development of lixisenatide, leading to this first approval for use in adults with type 2 diabetes.