AstraZeneca just launched its new Bydureon (exenatide once weekly) pen, which eliminates the need for manual patient-end reconstitution, in the US. As a reminder, the dual-chambered pen was approved by the FDA in March and recently received a positive CHMP opinion in Europe, paving the way for a likely European approval within the next few months. The dual-chambered pen’s simple “twist, tap, twist” procedure (most recently demonstrated at AZ’s AADE product theater) appears significantly more user-friendly than the current vial-syringe reconstitution process, though it is not quite as convenient as “ready-to-use” formulations like those for Novo Nordisk’s Victoza (liraglutide), Sanofi’s Lyxumia (lixisenatide), or Lilly's Trulicity (dulaglutide) - the latter, if approved, would be the first once-weekly GLP-1 agonist to be available as a ready-to-use formulation. Device administration and the “hassle factor” of reconstitution continue to be significant points of differentiation for GLP-1 agonists, and we are pleased to see AZ taking steps in a more patient-friendly direction. The company also plans to submit a Bydureon suspension formulation (which could enable an autoinjector device) in both the US and EU in 2015.