Pulmonary Outcomes of Fluticasone/Salmeterol via Dry Powder vs Metered-Dose Inhalers in Children with Moderate Asthma: A Randomized Crossover Trial

Abstract

Background: The effectiveness of inhaled therapy in childhood asthma depends not only on the pharmacological properties of the medication but also on the inhalation device and proper inhalation technique. Evidence comparing dry powder inhalers (DPIs) and metered-dose inhalers (MDIs) for combination inhaled corticosteroid/long-acting β2-agonist therapy in pediatric populations remains limited. Objectives: To compare pulmonary function outcomes after fluticasone/salmeterol administration via a DPI versus an MDI in children with moderate asthma using a randomized, crossover design. Methods: This randomized crossover clinical trial was conducted in 86 children with moderate asthma (age range: 6 - 12 years; 48% female; mean asthma duration: 3.4 ± 1.2 years; previous controller therapy: inhaled corticosteroids). Participants were randomly assigned to two treatment sequences (DPI→MDI or MDI→DPI), with each treatment period lasting 1 month. Results: Pulmonary function improved over time in both treatment sequences. Mean FEV1 increased from 76.02 ± 9.92 to 86.42 ± 7.38 in the DPI→MDI sequence and from 74.46 ± 12.18 to 85.82 ± 9.12 in the MDI→DPI sequence. However, no statistically significant differences were observed between DPI and MDI for FEV1 (P = 0.544), FEV1/FVC (P = 0.579), FVC (P = 0.359), or FEF25 - 75% (P = 0.671). Patient-reported comfort was slightly higher with DPI use. No treatment-related adverse events were reported. Conclusions: Fluticasone/salmeterol delivered via DPI and MDI resulted in similar improvements in pulmonary function in children with moderate asthma, with no statistically significant differences between the devices. Inhaler selection should be guided by patient preference, inhaler technique, accessibility, and clinical considerations rather than expected differences in efficacy.