Ex-vivo product performance of DiskusTMand TurbuhalerTMinhalers using inhalation profiles from patients with severe chronic obstructive pulmonary disease

AbstractDosing performance of dry powder inhalers is dependent on patient's inspiratory effort. This study compares the inhalation profiles generated by patients with severe obstructive lung disease using DiskusTMand TurbuhalerTMinhalers. The patient profiles are subsequently used to determine the dosing performance of fluticasone propionate DiskusTMand budesonide TurbuhalerTMinhalers.Inhalation profiles were recorded in COPD patients (FEV1≤30% predicted) as they inhaled with maximal effort through the inhalers. The profiles were used in an inhalation simulator to assess the dosing performance by measuring the total emitted dose and the fine particle mass for each inhaler type.Peak inspiratory flow was significantly higher through the DiskusTM(mean 82·3 l min−1) compared with TurbuhalerTM(mean 53·5 l min−1, difference = 28.8 l min−1;P