Comparison of budesonide/formoterol Turbuhaler with fluticasone/salmeterol Diskus for treatment effects on small airway impairment and airway inflammation in patients with asthma.

Background: A course of combination therapy with an inhaled corticosteroid (ICS) and a long-acting β(2) agonist (LABA) for asthma can improve lung function, asthma symptoms and reduce exacerbations. Because both medicinal substance and inhalation devices are associated with clinical efficacy, each ICS/LABA combination may have different features. This study aimed to compare the effects of two widely available formulations, budesonide/formoterol (BUD/FM) delivered by a Turbuhaler(®), and fluticasone/salmeterol (FP/SM) delivered by a Diskus(®), on small airway function and airway inflammation.

Methods: Asthmatic patients (n = 40) treated twice daily with FP/SM 250/50 μg with forced expiratory volume in 1 s values controlled above 80% of the predicted normal but with suspected persistent airway inflammation and small airway impairment were enrolled in the study. Patients were randomized into two groups, receiving either twice daily BUD/FM 320/9 μg or FP/SM 250/50 μg, and treatment efficacy was compared after 4 weeks. Outcomes included impulse oscillometry (IOS), fractional exhaled nitric oxide (FeNO), spirometry and Asthma Control Questionnaire (ACQ) scores.

Results: Patients in the BUD/FM group showed significant improvements in their IOS and spirometry parameters of small airway function, FeNO values and ACQ scores, compared with the FP/SM group. There were good correlations between IOS parameters, FeNO and ACQ score changes over the course of the treatment.

Conclusions: BUD/FM twice daily significantly improved small airway impairment and airway inflammation in asthmatic patients, leading to a reduction in asthma symptoms and achievement of good asthma control. In addition, improvement of small airway function may improve airway inflammation and/or lead to better controlled asthma.