Bronchodilator efficacy of 18 µg once-daily tiotropium inhalation via Discair^® versus HandiHaler^® in adults with chronic obstructive pulmonary disease: randomized, active-controlled, parallel-group, open-label, Phase IV trial

Abstract

PurposeTo compare the bronchodilator efficacy of 18 μg once-daily tiotropium inhalation administered via Discair® versus HandiHaler® in adults with moderate-to-severe chronic obstructive pulmonary disease (COPD).Patients and methodsFifty-eight patients with moderate-to-severe COPD were enrolled in this randomized, active-controlled, parallel-group, open-label, Phase IV non-inferiority trial. Patients were randomly assigned to a test group (n=29, inhalation with Discair) or a reference group (n=29, inhalation with HandiHaler). The primary efficacy parameter was the average maximum change in forced expiratory volume in 1 second (FEV1, in L). Change in forced vital capacity (FVC, in L), %FEV1 and %FVC, the standardized area under the response–time curve (AUC) for the absolute change in FEV1 and FVC, time to onset and peak of response, and safety data were also evaluated.ResultsThe test inhaler was non-inferior to the reference inhaler in terms of maximum change in FEV1 at 24 h (unadjusted change: 0.0017 L [95% confidence interval [CI]: −0.0777, 0.0812]; change adjusted for time to reach maximum change in FEV1 and smoking in pack-years: 0.0116 L [95% CI: −0.0699, 0.0931]), based on a non-inferiority margin of 0.100 L. There were also no significant differences between the two groups in maximum change in FVC value from baseline (0.3417 L vs 0.4438 L, P=0.113), percent change from baseline (22.235 vs 20.783 for FEV1, P=0.662; 16.719 vs 20.337 for FVC, P=0.257), and AUC0–24 h (2.949 vs 2.833 L for FEV1, P=0.891; 2.897 vs 4.729 L for FVC, P=0.178). There were no adverse events, serious adverse events, or deaths.ConclusionOur findings show that the Discair was non-inferior to the HandiHaler. More specifically, these devices had similar clinical efficacy in terms of time-dependent response over 24 h for patients with moderate-to-severe COPD.