Dual Bronchodilator Therapy as First-Line Treatment in Maintenance-Naïve Patients with Symptomatic COPD: A Pre-Specified Analysis of the EMAX Trial

INTRODUCTION: Limited prospective evidence is available to guide selection of first-line maintenance therapy in patients with COPD. This pre-specified analysis of the EMAX trial explored the efficacy and safety of dual- versus mono-bronchodilator therapy in maintenance-naïve and maintenance-treated patients. METHODS: The 24-week EMAX trial evaluated lung function, symptoms (including rescue medication use), exacerbations, and safety with umeclidinium/vilanterol, umeclidinium, and salmeterol in symptomatic patients at low exacerbation risk who were not receiving inhaled corticosteroids. Maintenance-naïve and maintenance-treated subgroups were defined by maintenance bronchodilator use 30 days before screening. RESULTS: The analysis included 749 (31%) maintenance-naïve and 1676 (69%) maintenance-treated patients. For both subgroups, improvements from baseline in trough FEV(1) at Week 24 (primary endpoint) were greater with umeclidinium/vilanterol versus umeclidinium (mean difference [95% CI]; maintenance-naïve: 44 mL [1, 87]; maintenance-treated: 77 mL [50, 104]), and salmeterol (maintenance-naïve: 128 mL [85, 171]; maintenance-treated: 145 mL [118, 172]), and in rescue medication inhalations/day over 24 weeks versus umeclidinium (maintenance-naïve: −0.44 [−0.73, −0.16]; maintenance-treated: −0.28 [−0.45, −0.12]) and salmeterol (maintenance-naïve: −0.37 [−0.66, −0.09]; maintenance-treated: −0.25 [−0.41, −0.08]). In maintenance-naïve patients, umeclidinium/vilanterol numerically improved scores at Week 24 for Transition Dyspnea Index versus umeclidinium (0.37 [−0.21, 0.96]) and versus salmeterol (0.47 [−0.10, 1.05]) and Evaluating Respiratory Symptoms–COPD versus umeclidinium (−0.26 [−1.04, 0.53]) and versus salmeterol (−0.58 [−1.36, 0.20]), with similar improvements seen in maintenance-treated patients. All treatments were well tolerated across both subgroups. CONCLUSION: Similar to maintenance-treated patients, maintenance-naïve patients receiving umeclidinium/vilanterol showed greater improvements in lung function and symptoms compared with patients receiving umeclidinium or salmeterol. These findings provide support for the consideration of dual bronchodilator treatment in symptomatic maintenance-naïve patients with COPD.