Comparison of early effects of budesonide/formoterol maintenance and reliever therapy with fluticasone furoate/vilanterol for asthma patients requiring step-up from inhaled corticosteroid monotherapy.

Background: If asthma patients fail to achieve symptom control using a medium dose of inhaled corticosteroid (ICS) alone, addition of a long-acting β2 agonist (LABA) is the preferred treatment. Currently, there are several combinations of ICS/LABA that are available, each of which has a different property. Here, we aimed to compare the early effects of budesonide/formoterol (BUD/FM; Symbicort(®)) for maintenance and reliever therapy (SMART) with a fixed dose of fluticasone furoate/vilanterol (FF/VI; Relvar(®)).

Methods: Inadequately controlled asthma patients (defined as having an Asthma Control Questionnaire, 5-item version [ACQ5] score≥1.5) with a fractional exhaled nitric oxide (FeNO) value > 35 ppb, who had been treated with a medium dose of ICS alone, were enrolled. Patients were randomized into two groups and treated with two inhalations twice-daily of BUD/FM 160/4.5 μg plus as-needed BUD/FM (SMART group, n = 15) or one inhalation once-daily of FF/VI 100/25 μg plus as-needed procaterol (FF/VI group, n = 15) for 4 weeks. Outcomes including FeNO, impulse oscillometry (IOS) parameters and ACQ5 scores were measured at 0, 2 and 4 weeks.

Results: Both groups showed improvement in airway inflammation, pulmonary function and symptoms from baseline to 2 weeks. From 2 to 4 weeks, the SMART group exhibited continuous improvement in most measured parameters, whereas improvement in the FF/VI group seemed to reach a plateau transiently. Consequently, the SMART group showed significant improvement in the FeNO, IOS parameters (resonance frequency and integrated area of low frequency reactance) and ACQ5 score as compared with the FF/VI group at 4 weeks.

Conclusion: As compared with the FF/VI group, the SMART group achieved a greater improvement in FeNO, small airway parameters regarding IOS and ACQ score, in patients with airway inflammation and uncontrolled symptoms treated with a medium dose of ICS alone. In this 4-week study, these two ICS/LABA combination therapies showed different treatment outcomes; they must be investigated further to clarify suitable patient characters and the long term efficacies for each combination.