The present invention relates to compositions forming a low viscosity mixture of: a) 20 -50 wt.% of at least one diacyl glycerol； b) 20- 54 wt.% of at least one phosphatidyl choline (PC)； c) 5- 15wt.% of at least one biocompatible ,organic mono- alcoholic solvent； d) 1 to 20 wt.% polar solvent e) 5 to 150 mg/ml of at least one peptide somatostatin receptor agonist comprising pasireotide； f) optionally at least one antioxidant； wherein the ratio of components a:b is in the range 40:60 to 54:46； wherein the pre formulation forms, or is capable of forming , at least one liquid crystalline phase structure upon contact with excess aqueous fluid. The invention further relates to methods of treatment comprising administration of such compositions , and to pre- filled administration devices and kits containing the formulations.
