FIELD: organic chemistry, pharmacy. SUBSTANCE: invention relates to microparticles of the novel salts consisting of peptide cation containing at least one basic group and polyester anion with terminal carboxy-groups and methods of their synthesis used in production of pharmaceutical compositions of prolonged effect. Particles can be used for production of pharmaceutical preparations of prolonged effect being these salts can be taken as pure form or with excess of free nonbound peptide form or with excess of free polyester. EFFECT: improved quality of microparticles. 18 cl, 1 tbl
