Breath-synchronized plume-control inhaler for pulmonary delivery of fluticasone propionate

A novel breath-synchronized, plume-control inhaler (Tempo inhaler) was developed to overcome limitations of a pressurized metered-dose inhaler. This report compared the Tempo inhaler and a commercial inhaler for fine particle distribution and lung deposition of fluticasone propionate. In vitro fine particle distribution was determined using the Andersen Cascade Impactor at inspiration rates of 28.3 and 45L/min. In vivo lung deposition was assessed in a randomized, two-arm, crossover study of (99m)Tc-radiolabeled fluticasone propionate in 12 healthy adult subjects, analyzed by gamma scintigraphy. In vitro: fine particle fractions at 28.3 and 45L/min were 88.6+/-3.6% and 89.2+/-3.0% (Tempo inhaler) versus 40.4+/-4.7% and 43.1+/-4.4% (commercial inhaler). In vivo: lung deposition was 41.5+/-9.8% (Tempo inhaler) versus 13.8+/-7.4% (commercial inhaler) and oropharyngeal deposition was 18.3+/-7.7% (Tempo inhaler) versus 76.8+/-7.1% (commercial inhaler). Variability of lung deposition was reduced from 55% (commercial inhaler) to 24% (Tempo inhaler) of the delivered dose. The Tempo inhaler produced significantly higher fine particle fraction values, reduced oropharyngeal deposition by 75%, and increased whole, central, intermediate, and peripheral lung delivery by more than 200%. Thus, the Tempo inhaler enhances efficient drug delivery to the lungs.