Budesonide/Formoterol Easyhaler®: Performance Under Simulated Real-Life Conditions

Introduction We compared in vitro drug delivery characteristics of two budesonide/formoterol dry powder inhalers, the Bufomix Easyhaler ® and the budesonide/formoterol Turbuhaler ® , at different patient air flow rates, and to test dose delivery from the Easyhaler in stressed conditions exposed to moisture, dropping, vibration and freezing/thawing. Methods A total of 36 inhalers from two batches of both products (160/4.5 µg strength) were used when comparing the effect of flow rate; six inhalers for each of the three flow rates for uniformity of delivered dose (DD), fine particle dose (FPD), mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD). Consistency of DD, FPD, MMAD and GSD were determined for each inhaler at three different flow rates: 10th, 50th and 90th percentile air flows. Dosing properties as a function of inhaler life were tested. The effects of moisture, dropping, vibration and freezing/thawing on DD and FPD were tested with two to four inhalers per test using all three strengths of Easyhaler: 80/4.5, 160/4.5 and 320/9 µg. Results The Easyhaler, 160/4.5 µg, showed statistically significantly better dose consistency (expressed as percentage of labelled dose) at all three inhalation flows compared with the Turbuhaler, 160/4.5 µg, ( p