Abstract
Background: It has been reported that a blood eosinophil count of ≥2% identifies those COPD patients who benefit from ICS in terms of reduction of exacerbations (Bafadhel M et al, AJRCCM 2012;186:48–55).
Objective: To determine if an eosinophil count of ≥2% is a marker for greater responsiveness to bronchodilator treatment with umeclidinium (UMEC), vilanterol (VI) or UMEC/VI in COPD.
Methods: We investigated the effect of UMEC, VI and UMEC/VI compared with placebo on FEV1, SGRQ and transitional dyspnoea index (TDI) in patients whose eosinophil counts were recorded at baseline. A total of 4,713 patients from four 6-month studies were included (DB2113360 [NCT01316900]; DB2113374 [NCT01316913]; DB2113361 [NCT01313637]; DB2113373 [NCT01313650]) of whom 36% had an eosinophil count of ≥2%. Analysis was performed using a repeated measures model including terms for treatment, day, eosinophil subgroup (≥2%, <2%) and their interactions.
Results: For trough FEV1 (mean of 23h and 24h post-dose) at the 6-month time point, patients with an eosinophil count of ≥2% had mean differences from placebo of 205mL for UMEC/VI 62.5/25mcg, 130mL for UMEC 62.5mcg and 100mL for VI 25mcg. Patients with an eosinophil count of <2% had mean differences from placebo of 197mL for UMEC/VI 62.5/25mcg, 139mL for UMEC 62.5mcg and 100mL for VI 25mcg. A similar lack of difference for patients with eosinophil counts ≥2% or <2% was seen for FEV1 at other time points and for SGRQ and TDI endpoints.
Conclusion: Response to treatment in terms of health-related quality of life, bronchodilator response or dyspnoea for UMEC, VI or UMEC/VI in COPD was similar for patients with eosinophil counts ≥2% or <2% at baseline.
Funding: GSK
- © 2014 ERS