Comparison of Beclomethasone Dipropionate Delivery by Easyhaler ® Dry Powder Inhaler and pMDI Plus Large Volume Spacer

Dry powder inhalers (DPIs) provide a means of delivering inhaled asthma drugs without the use of propellants. Easyhaler^® is a multidose DPI, delivering 200 doses of beclomethasone dipropionate (BDP), 200 μg/dose. A gamma scintigraphic study has been carried out in 10 healthy volunteers to compare the deposition of BDP from Easyhaler^® with that from a pressurized metered dose inhaler (pMDI) coupled to a Volumatic^® spacer device delivering 250 μg BDP per dose. The spacer was used without any pretreatment to reduce static charge on the spacer walls. The study was conducted according to an open, randomized, crossover design. The volunteers inhaled the study drug using optimal inhalation technique for both devices. Lung deposition of ^99mTc-labeled BDP averaged 18.9% (SD 9.5%) of the metered dose for Easyhaler^®, and 11.2% (SD 5.3%) for pMDI plus spacer (p < 0.05); when the data were expressed as mass of BDP deposited in the lungs, the difference in lung deposition just failed to reach statistical significance (Easyhaler^® 37.8 μg; pMDI plus spacer 28.0 μg). Oropharyngeal deposition was significantly reduced by use of the spacer. The results of this study show that Easyhaler^® delivers drug more efficiently to the lungs than pMDI plus Volumatic^® spacer when no measures are taken to eliminate static charge on the spacer walls.