Rationale In the randomised, double-blind, Phase IIIb OTEMTO® 1 and 2 studies (NCT01431274; NCT01431287), the combination of tiotropium (T), a long-acting muscarinic antagonist, plus olodaterol (O), a long-acting β2-agonist, showed meaningful improvements in quality of life (St George’s Respiratory Questionnaire [SGRQ]) and lung function in patients with moderate to severe COPD after 12 weeks’ treatment compared to T alone or placebo. This post hoc analysis investigated whether symptomatic status at inclusion, as measured by the modified Medical Research Council (mMRC) dyspnoea scale and the Baseline Dyspnoea Index (BDI), influenced lung-function and SGRQ responses.
Methods Patients aged ≥40 years received T/O 2.5/5 µg, T/O 5/5 µg, T 5 µg or placebo once daily for 12 weeks via Respimat® inhaler. SGRQ total score and lung function (FEV1 area under the curve from 0–3 hours [AUC0–3] and trough FEV1 responses) were primary end points. Patients completed the mMRC and BDI scales at baseline. We report comparisons between T/O 5/5 µg, T 5 µg and placebo.
Results 1621 patients were evaluated: 736 patients (45%) had mMRC scores <2, 883 patients (54%) ≥2 (scored from grade 0–5, lower is better); 418 patients (26%) had BDI scores <6, 1201 patients (74%) ≥6 (scored from 0–12, higher is better). Patients were distributed evenly across treatment arms with respect to mMRC and BDI scores, and baseline characteristics were consistent across treatment arms. Improvements in FEV1 AUC0–3 and trough FEV1 were observed with T/O compared to T and placebo in patients with mMRC score <2 and ≥2, as well as in patients with BDI score ≥6 and <6 (Table). All BDI and mMRC groups demonstrated improvements in SGRQ with T/O compared to placebo above the minimal clinically important difference.
Conclusions There was a trend towards better lung-function improvement with T/O versus T or placebo in less symptomatic patients assessed by baseline BDI. More severe dyspnoea by mMRC category was associated with improved SGRQ with T/O versus T or placebo, but did not affect lung-function improvement. Overall, T/O provided lung-function and quality of life benefits regardless of symptomatic status prior to treatment.
Funding Boehringer Ingelheim.
Please refer to page A274 for declarations of interest in relation to abstract P299.