Rationale The once-daily combination of tiotropium (T), a long-acting muscarinic antagonist, and olodaterol (O), a long-acting β₂-agonist, has demonstrated efficacy and safety in chronic obstructive pulmonary disease (COPD).¹ Recently, it has been demonstrated that patients with milder disease (GOLD 2) have better bronchodilator responses compared to those with more severe disease. This post hoc analysis investigated whether the response to T/O and to T alone is influenced by forced expiratory volume in 1 second (FEV₁) American Thoracic Society (ATS) category (mild, moderate or severe).

Methods In total, 5162 patients were randomised to O 5 µg, T 2.5 µg, T 5 µg, T/O 2.5/5 µg or T/O 5/5 µg (via Respimat^® inhaler) in two 52-week, parallel-group, double-blind studies (TONADO^® 1 and 2: NCT01431274; NCT01431287). This post hoc analysis focuses on the T 5 µg and T/O 5/5 µg analyses. Primary efficacy end points were trough FEV₁ response (ie, change from baseline) and FEV₁ area under the curve from 0–3 hours (AUC_0–3) response. Data are presented for patients by ATS category subgroups: mild (predicted FEV₁ ≥50%), moderate (35 ≤ 50%) and severe (<35%), using data pooled from both of the TONADO^® studies.

Results In all disease-severity categories, the improvements in trough FEV₁ and FEV₁ AUC_0–3 were larger with T/O compared to T alone. However, trough FEV₁ and FEV₁ AUC_0–3 responses were generally greater in patients with mild (T/O versus T: both p < 0.0001) or moderate (T/O versus T: p < 0.001 and p < 0.0001, respectively) COPD versus those with severe COPD (T/O versus T: p < 0.01 and p < 0.0001, respectively) at baseline (Table). Treatments were well tolerated across all ATS categories and similar responses were observed in both of the studies individually.

Conclusions These data build on the analysis of the GOLD 2 population from TONADO^® and confirm that patients with mild to moderate disease derive greater benefits with T/O than with T. There was an overall trend towards greater lung-function improvement with T/O or T alone in patients with mild/moderate versus severe airflow obstruction.

Funding Boehringer Ingelheim.

Reference

1. Buhl R, et al. Eur Respir J 2015;45:969–979.

ReferencePlease refer to page A273 for declarations of interest in relation to abstract P295.