Bronchodilator efficacy of tiotropium in patients with mild to moderate COPD.

AIMS: Evaluation of tiotropium efficacy in patients with mild chronic obstructive pulmonary disease (COPD) defined by the 2003 Swedish Society of Respiratory Medicine guidelines (post-bronchodilator FEV1/FVC <70%; FEV1 >60% predicted).

METHODS: In this 12-week, randomised, double-blind, placebo-controlled study of tiotropium 18 mcg once daily versus placebo, respiratory function was assessed on Days 1, 15 and 85 (baseline: pre-dose Day 1).

RESULTS: Mean+/-SD baseline FEV1 (% predicted) was 73.4+/-12.5 (tiotropium, n=107; placebo, n=117). Tiotropium significantly improved change from baseline in area under the curve from pre-dose to 2 hours post-dose (AUC0-2 h) FEV1 versus placebo, by 166+/-26 mL (mean+/-SE) at study end (p<0.0001). With tiotropium, there were significant increases in the change in AUC0-2 h FVC versus baseline, and trough FEV1 and FVC, versus placebo, on all test days (p<0.01). Adverse event rates were similar.

CONCLUSION: Compared with placebo, tiotropium improved lung function in patients with mild COPD.