Singh D, et al. - Authors gauged the bronchodilator effects, pharmacokinetics and safety of PUR0200 in patients with chronic obstructive pulmonary disease (COPD). In COPD patients, bronchodilation was caused by PUR0200 treatment. This bronchodilation was similar in magnitude to that caused by tiotropium HandiHaler (HH). Similar clinical effect on lung function to be achieved with PUR0200 using a lower metered dose of tiotropium compared with tiotropium HH was enabled by this.