The present invention relates to a process for preparing a
powder formulation for
inhalation for use in a
dry powder inhaler, the
powder formulation comprising: (A) a carrier comprising: (a) a physiologically acceptable
coarse particle fraction of the carrier having a particle size of at least 60 microns; and optionally (b) a fine
particle fraction comprising a physiologically acceptable
excipient wherein at least 90% of all of the fine particles have a volume
diameter of less than 15 microns, (B) micronized particles of
glycopyrronium bromide, an
inhalation corticosteroid (ICS) and optionally a long-acting beta2-
agonist (LABA) as active ingredients, wherein the method comprises: (i) preparing, by co-
grinding, microparticles consisting of
glycopyrronium bromide and a first portion of ICS in a weight ratio of 80: 20 to 70: 30, wherein the volume
diameter of the microparticles is not greater than 15 microns; (ii) mixing a carrier, the remainder of the ICS and an optional long-acting beta2-
agonist to obtain a first mixture; and (iii) adding the co-milled microparticles obtained in step (i) to the first mixture obtained in step (ii) to obtain a second final mixture.