Process to control particle size

摘要

A multi-stage process to control the particle size of a pharmaceutical substance comprising the steps of: passing the pharmaceutical substance through a first stage of a particle size reduction process with a first set of particle size control parameters to obtain a feedstock of reduced median particle size and lesser distribution of median particle size for a second stage of a particle size reduction process; passing the feedstock, through a second stage of a particle size reduction process with a second set of particle size control parameters; optionally, using the product of the second stage or subsequent stages as a feedstock in further stages of a multi-stage particle size reduction process with a set of particle size control parameters for each stage; and collecting a pharmaceutical substance with a median particle size greater than 10 μm and with a narrow, reproducible distribution of median particle sizes.

主权项

1. A multi-stage process to control the particle size of a pharmaceutical substance comprising the steps of:
passing an initial feedstock of the pharmaceutical substance through a first stage of the multi-stage particle size reduction process, the first stage having a first set of particle size control parameters to obtain a further feedstock for at least a second stage of the multi-stage particle size reduction process; passing the further feedstock through the second stage of the multi-stage particle size reduction process, the second stage having a second set of particle size control parameters to obtain a pharmaceutical substance with a reduced median particle size and narrower distribution of median particle size than the further feedstock; and collecting the pharmaceutical substance of the final stage of the multi-stage particle size reduction process with a median particle size greater than 10 μm and with a narrow reproducible distribution of median particle size,wherein at least 50% of the particles of the pharmaceutical substance of the final stage have a particle size deviating no more than between 1 μm and 10 μm from the median particle size.