Bronchodilator efficacy of tiotropium/formoterol (18/12 µg once daily via a Discair inhaler), tiotropium alone (18 µg by Handihaler) or combined with formoterol (12 µg twice daily by Aerolizer) in adults with moderate-to-severe stable COPD.

The bronchodilator efficacy of a once-daily fixed-dose combination of tiotropium/formoterol (18/12 µg administered via a dry-powder inhaler, Discair) [TIO/FORM group] vs a single-dose of tiotropium (18 µg) by Handihaler alone [TIO group], or combined with formoterol 12 µg twice-daily by Aerolizer [TIO/FORM group] was compared in patients with moderate-to-severe stable COPD. COPD patients were randomized (28 patients/group) to receive TIO/FORM, TIO or TIO/FORM. AUC for the changes in FEV and FVC over a 24-h period; bronchodilator response (100 ml improvement in FEV) in the first 30 min; maximum changes in FEV and FVC; and safety data were recorded. The primary endpoint was to confirm the non-inferiority of TIO/FORM vs TIO/FORM in terms of the AUC for the changes in FEV over a 24-h period. Changes in AUC for FEV and FVC were similar for TIO/FORM and TIO/FORM, and were superior to TIO ( < 0.001). A positive bronchodilator response at 30 min was demonstrated in 50%, 64%, and 71% of patients in the TIO, TIO/FORM, and TIO/FORM groups, respectively (NS). Maximum FEV and FVC changes were measured as 0.25/0.41 L, 0.32/0.49 L, and 0.37/0.53 L, for TIO, TIO/FORM, and TIO/FORM, respectively (FEV: TIO/FORM vs TIO,  = 0.0017 and TIO/FORM vs TIO/FORM,  = 0.4846); no differences were recorded between the combination groups. The 24-h bronchodilator efficacy of TIO/FORM 18/12 µg once-daily by Discair was non-inferior to a combination of tiotropium 18 µg by Handihaler plus formoterol 12 µg twice-daily by Aerolizer, and superior to tiotropium 18 µg monotherapy by Handihaler.