A Randomized, Noninferiority Trial Comparing ICS + LABA with ICS + LABA + LAMA in Asthma-COPD Overlap (ACO) Treatment: The ACO Treatment with Optimal Medications (ATOMIC) Study.

BACKGROUND Current guidelines for the treatment of asthma and chronic obstructive pulmonary disease overlap (ACO) recommend initial treatment using inhaled corticosteroids (ICSs) plus 1 or more bronchodilators. OBJECTIVE To clarify which therapeutic effect is better between the ICS + long-acting β2 agonist (LABA) and ICS + LABA + long-acting muscarinic antagonist (LAMA) treatment in patients with ACO. METHODS We conducted a multicenter, 48-week, randomized, noninferiority trial. Patients with ACO were enrolled if they were treated with a moderate to high dose of ICS + LABA. In total, 303 patients were involved in the present trial, with 149 receiving ICS + LABA + LAMA. The primary end point was the time to first exacerbation. Secondary outcomes included changes in FEV1, forced vital capacity, FEV1/forced vital capacity ratio, asthma control, blood eosinophil count, and fractional exhaled nitric oxide. RESULTS In the ICS + LABA treatment group, 29 of 154 patients (18.83%) experienced exacerbation, whereas 28 of 149 patients (18.79%) experienced exacerbation in the ICS + LABA + LAMA treatment group. The results of this noninferiority study were ultimately inconclusive (hazard ratio, 1.1; 95% CI, 0.66-1.84). However, the patients treated with the addition of LAMA showed significant improvements in FEV1 and forced vital capacity (P < .001). Asthma control did not improve in either group. CONCLUSIONS Although this study was unable to conclude that ICS + LABA treatment is not inferior to ICS + LABA + LAMA in terms of exacerbation, it is obvious that the ICS + LABA + LAMA treatment group had improved lung function in ACO.