Abstract: A copolymer comprising an N-acylated derivative, and a composition comprising said copolymer and a polypeptide, said polypeptide comprising at least one effective ionogenic amine, wherein at least 50 percent, by weight, of said polypeptide present in said composition is ionically bound to said polymer.

Abstract: The invention pertains to a process for making encased bound microparticles by nebulizing a dispersion of the bound microparticles into a solution of an encasing polymer and into a liquid, non-solvent of said encasing polymer.

Abstract: A copolymer comprising an N-acylated derivative, and a composition comprising said copolymer and a polypeptide, said polypeptide comprising at least one effective ionogenic amine, wherein at least 50 percent, by weight, of said polypeptide present in said composition is ionically bound to said polymer.

Abstract: A biodegradable polyester prepared from lactic acid, and, optionally, other hydroxy acid or acids. The polyester contains 4-100 carboxyl groups and has an average molecular weight of 1,000 to 200,000 g/mol. Also disclosed are methods of making such polyesters.

Abstract: Disclosed is a sustained release pharmaceutical composition. The composition includes a polyester containing a free COOH group ionically conjugated with a bioactive polypeptide comprising at least one effective ionogenic amine, wherein at least 50% by weight of the polypeptide present in the composition is ionically conjugated to the polyester.

Abstract: A process for drying a solution containing the material. The process includes the following steps: (1) subjecting the solution to vacuum-assisted freezing by introducing the solution into an evacuated chamber in the form of a spray, the droplets of which are at a sufficiently low temperature to ensure that they freeze at the vacuum pressure inside the chamber; (2) collecting the frozen droplets of the solution on a collecting surface of the chamber and controlling the temperature of the collecting surface and the pressure within the chamber so that the frozen solvent sublimes from the collected frozen droplets.

Abstract: A composition including a polyester containing one or more free COOH groups ionically conjugated with a bioactive polypeptide comprising at least one effective ionogenic amine, wherein the polyester contains a member selected from the group of L-lactic acid, D-lactic acid, DL-lactic acid, .epsilon.-caprolactone, p-dioxanone, .epsilon.-caprolic acid, alkylene oxalate, cycloalkylene oxalate, alkylene succinate, .beta.-hydroxybutyrate, substituted or unsubstituted trimethylene carbonate, 1,5-dioxopan-2-one, 1,4-dioxepan-2-one, glycolide, glycolic acid, L-lactide, D-lactide, DL-lactide, meso-lactide, and any optically active isomers, racemates or copolymers thereof, and at least 50%, by weight, of the polypeptide present in the composition is ionically conjugated to said polyester.