US Patent 8628754 Highly efficient delivery of a large therapeutic mass aerosol

A method for delivering an agent to the pulmonary system, in a single, breath-activated step or a single breath, comprises administering from a receptacle enclosing a mass of particles, to a subject's respiratory tract, particles which have a tap density of less than 0.4 g/cm3 and deliver at least about 50% of the mass of particles. The particles are capable of carrying agents. The agent is (1) part of the spray-drying pre-mixture and thereby incorporated into the particles, (2) added to separately-prepared particles so that the agent is in chemical association with the particles or (3) blended so that the agent is mixed with, and co-delivered with the particles.