The present invention relates to pre-formulations comprising: a) at least one di-acyl lipid; b) at least one phospholipid; c) at least one biocompatible, organic solvent; d) an alkyl ammonium EDTA salt; and e) at least one somatostatin receptor agonist; wherein the pre-formulation has a water content in the range of 0 to 1.0 wt %. The invention further relates to methods of treatment comprising administration of such pre-formulations, to pre-filled administration devices and kits containing the formulations, to the use of an alkylammonium EDTA salt to reduce the decomposition of the lipid components and/or any active agent contained within the pre-formulation.