Rationale The efficacy and safety of the once-daily combination of tiotropium (T), a long-acting muscarinic antagonist (LAMA), and olodaterol (O), a long-acting β₂-agonist (LABA), for the treatment of chronic obstructive pulmonary disease (COPD) has been established. We investigated whether there was a difference in the characteristics of COPD patients with and without baseline maintenance treatment.

Methods Two replicate, randomised, 52-week, double-blind, parallel-group, Phase III trials (NCT01431274; NCT01431287; n = 5162) assessed the efficacy and safety of once-daily treatment with T+O (2.5/5 μg; 5/5 μg; Respimat® inhaler) compared to the individual components. Baseline characteristics of COPD patients within Global initiative for chronic Obstructive Lung Disease (GOLD) subgroups 2 and 3/4, with/without maintenance treatment (prior LABA, LAMA or both at baseline), are presented, based on data from the pooled set.

Results Most patients received baseline maintenance treatment (3037 vs 2121) and of those, there was a greater proportion of GOLD 3/4 compared to GOLD 2 patients (52.58% vs 47.42%, respectively). An opposite trend was observed in patients not receiving maintenance treatment (GOLD 3/4, 45.87% vs GOLD 2, 54.13%). The proportion of current smokers was lower in GOLD 3/4 than GOLD 2 patients, as expected (Table); nevertheless, irrespective of GOLD stage, there was a greater proportion of smokers without maintenance treatment than with maintenance treatment (42.81% vs 32.86%, respectively). As expected, pulmonary function was reduced in GOLD 3/4 compared to GOLD 2 patients, although it appeared comparable between patients with and without maintenance treatment. Of the patients with maintenance treatment, a considerably greater proportion received inhaled steroids compared to those without prior LAMA/LABA treatment (69.67% vs 15.51%, respectively). Furthermore, a smaller proportion of patients without prior LAMA/LABA treatment received short-acting β-adrenergics compared to those with maintenance treatment (Table 1). Of the GOLD 3/4 patients without baseline maintenance treatment, 43.4% were not receiving any other pulmonary medication.

Conclusions A high proportion of GOLD 3/4 patients not receiving maintenance treatment were not receiving any other pulmonary medication. One could hypothesise that these patients had either been diagnosed recently or that they were not treated according to current COPD guidelines.