The present invention relates to compositions forming a low viscosity mixture of: a) at least one neutral diacyl lipid, such as a diacyl glycerol b) at least one phospholipid, such as a phosphatidyl choline c) at least one biotolerable solvent, such as an oxygen containing solvent d) at least one GLP-1 analogue wherein the pre-formulation forms, or is capable of forming, at least one liquid crystalline phase structure upon contact with an aqueous fluid. The invention further relates. to methods of treatment comprising administration of such compositions, especially in treating diabetes, and to pre-filled administration devices and kits containing the formulations.
