Comparison of Two pMDIs in Adult Asthmatics: A Randomized Double-blinded Double-dummy Clinical Trial

Background Only a few studies directly compared therapeutic efficacies and safety between two pressurized metered dose inhalers (pMDIs) in asthma. Objective We compared asthma treatment outcomes, safety, and patient preferences between formoterol/beclomethasone (FORM/BDP), a pMDI with extra-fine particles, and formoterol/budesonide (FORM/BUD), another pMDI with non-extra-fine particles. Methods In this randomized, double-blind, double-dummy parallel group study, 40 adult asthmatics were randomized to the FORM/BDP group (n = 18; active FORM/BDP and placebo FORM/BUD) or the FORM/BUD group (n = 22; active FORM/BUD and placebo FORM/BDP). During two visits (baseline and end of 8-week treatment), subjects were asked to answer questionnaires including asthma control test (ACT), asthma control questionnaires (ACQ), and Quality of Life Questionnaire for Adult Korean Asthmatics (QLQAKA). Lung function, compliance with inhaler, and skills in handling inhalers were also assessed. Results Ten in the FORM/BDP group and fourteen in the FORM/BUD group completed follow-up visits. ACT, ACQ, QLQAKA (a primary outcome), and adverse events did not differ between two groups. We found that FEV1/FVC and FEF25-75 increased more in the FORM/BDP group than in the FORM/BUD group. Regarding preference, subjects responded that the flume velocity of FORM/BDP was higher, but more adequate than that of FORM/BUD. They also answered that FORM/BDP reached the trachea and bronchus and irritated them significantly more than FORM/BUD. Conclusion pMDI with extra-fine particles may relieve small airway obstruction more than that with non-extra-fine particles despite no significant differences in overall treatment outcomes. Some asthmatics have a misconception that high flume velocity of pMDIs is adequate.