Patent ID: 7871977

Claim:
A process for producing a sterile suspension of at least one slightly soluble basic peptide complex, which comprises, under aseptic conditions: a) i) mixing a sterile solution comprising at least one of a salt or a complex of a basic peptide and of an aliphatic or aromatic organic carboxylic acid and/or salts thereof in a solvent or solvent mixture, optionally with the addition of solubility-increasing and/or agglomeration-suppressing additives; or a) ii) combining and mixing a sterile solution of a salt or complex of at least one basic peptide in a solvent or solvent mixture and a sterile solution of an aliphatic or aromatic organic carboxylic acid and/or salts thereof in a solvent or solvent mixture, optionally with the addition of solubility-increasing and/or agglomeration-suppressing additives; b) generating, by mixing and addition of a diluent or diluent mixture in one or more steps, a suspension of a slightly soluble basic peptide complex of the basic peptide with the carboxylic acid, which complex precipitates at the latest after addition of the diluent or diluent mixture, c) depleting, while mixing in a continuous or stepwise separation process, the solvent or solvent mixture, free non-peptide ions, excess carboxylic acid and optionally added solubility-increasing and/or agglomeration-suppressing additives in the resulting suspension, with the liquid content of the suspension being reduced and optionally adding further diluent or diluent mixture, and d) optionally adding to the slightly soluble basic peptide complex, while mixing the sterile suspension during c) and/or thereafter, one or more pharmaceutical excipients, carriers and/or bulking agents, wherein in a) the at least one of a salt or a complex of a basic peptide is an acetate salt of at least one LHRH antagonist selected from the group consisting of cetrorelix, teverelix, and ozarelix (D-63153), the salt of at least one carboxylic acid is selected from the group consisting of embonic acid, citric acid, and palmitic acid, and the solvent is an aqueous ethanolic solvent mixture having an ethanol content of from 50 to 90% (m/m), in c) water is added as a further diluent, and a molar ratio of the basic peptide to carboxylic acid in the slightly soluble basic peptide complex is between 2:1 and 1:2.