The Effect of Reducing the Fine-Particle Mass of Salmeterol from Metered-Dose Inhalers on Bronchodilatation and Bronchoprotection Against Methacholine Challenge: A Randomized, Placebo-Controlled, Double-Blind, Crossover Study

FPM from different MDI formulations may affect the bronchoprotective properties of salmeterol. In this study, the formulation with the smaller FPM was associated with less-effective bronchoprotection, although there was no difference in bronchodilatation. This study did not demonstrate noninferiority of the investigational HFA formulation to the CFC formulation in terms of protection against methacholine-induced bronchial hyperresponsiveness.