The present scoping study was designed to determine the potential impact of variable inhalation technique on fine particle mass (FPM) emitted from the widely prescribed Diskus* passive DPI (GSK) compared with inhalation of the same active pharmaceutical ingredients (APIs) via a pMDI with antistatic adult AeroChamber Plus* Flow Vu* VHC either tidally breathing or taking a slow inhalation followed by a breath-hold. Inspiratory flow rate-elapsed time profiles were initially acquired with three volunteer adult participants, trained in the use of both inhalers, using a pneumotachometer with its own mouthpiece attached to the mouthpiece of the inhaler, which was rendered incapable of delivering medication. Subsequently, each inhalation waveform was re-played via an ASL5000 breathing simulator in order to actuate either an Advair* Diskus* DPI (250 μg/actuation fluticasone propionate (FP) + 50 μg/actuation salmeterol xinafoate (SX)) or an Advair* Evohaler* pMDI (250 μg/actuation FP + 25 μg/actuation SX with VHC. In each case, the emitted aerosol was sampled via a Next Generation Impactor (NGI) operated at either 60 L/min, or at 30 L/min alone for pMDI + VHC evaluations. Variation in breathing profile parameters was observed in both delivery platforms, however, FPM<5.0 mm for either API delivered by pMDI with VHC was higher and more consistent across all breathing patterns from the three volunteers.
Inhalation breathing patterns have the potential to differ greatly from one individual to another, in either delivery platform. Such variability appears to impact the fine particle mass delivery more so with the DPI platform than the MDI with VHC.