SLOW RELEASE PHARMACEUTICAL COMPOSITION MADE OF MICROPARTICLES COMPRISING PLGA, LHRH AND LACTIC ACID

摘要

Disclosed is a pharmaceutical composition made of microparticles for the slow release of an LHRH agonist, such as triptorelin, at least during a period covering the 6th month after injection of said composition, said composition comprising a mixture of a first formulation of microparticles and a second formulation of microparticles, wherein a) the microparticles of said first formulation are made of a copolymer of the PLGA type which incorporates said LHRH agonist in the form of a water insoluble peptide salt; said copolymer comprising at least 85 percent (molar) of lactic acid and having an inherent viscosity between 0.55 and 0.75 dl/g, as measured in chloroform at 25 degrees C and at a polymer concentration of 0.5 g/dL; b) the microparticles of said second formulation are made of a copolymer of the PLGA type which incorporates said LHRH agonist in the form of a water insoluble peptide salt and which comprises an amount of lactic acid between 70 percent and 80 percent (molar); the microparticles of said first and second formulations furthermore having a size distribution defined as follows: - D (v,0.1) is between 10 and 30 micrometers, - D (v,0.5) is between 30 and 70 micrometers, - D (v,0.9) is between 50 and 110 micrometers Also disclosed is the use of the composition for treating prostate cancer.