Sustained release formulations of soluble peptides in water

The present invention relates to a sustained release formulation of a peptide, preferably a somatostatin such as octreotide, e.g., pamoate. The active ingredient is present in a polymeric carrier, preferably poly (lactic-co-glycolic acid). The formulation is preferably a depot formulation in the form of microparticles. The invention also includes an improved method for preparing microparticles of active principle in biodegradable and biocompatible carrier.