A systematic review of comparative studies of tiotropium Respimat® and tiotropium HandiHaler® in patients with chronic obstructive pulmonary disease: does inhaler choice matter?

BACKGROUND: In many countries worldwide, the long-acting anticholinergic drug tiotropium is available as a dry powder formulation delivered by means of the HandiHaler® inhalation device and as an aqueous solution delivered via the Respimat® Soft Mist™ Inhaler. Tiotropium HandiHaler® is a single-dose, dry powder, breath-actuated inhaler that provides delivered doses and lung deposition of tiotropium that are, over a wide range, not influenced by the severity of chronic obstructive pulmonary disease (COPD). Tiotropium Respimat® is a propellant-free, multi-dose inhaler that delivers a metered dose of medication as a fine, slow-moving, long-lasting soft mist, independently of patient inspiratory effort. The high fine-particle fraction of droplets produced by the Respimat® inhaler optimizes the efficiency of drug delivery to the lungs.

METHODS: To help inform the choice of tiotropium inhaler for prescribers and patients, this systematic review summarizes the available pharmacokinetic, efficacy and safety data from comparative studies of tiotropium Respimat® and tiotropium HandiHaler® in COPD, focusing on the licensed once-daily doses of 5 and 18 μg, respectively. Data sources reviewed include publications and abstracts identified from database searches.

RESULTS: Published evidence from comparative studies suggests that tiotropium Respimat® 5 μg and tiotropium HandiHaler® 18 μg provide similar clinical outcomes in patients with COPD.

CONCLUSIONS: The findings indicate that physicians can base their decision about an inhaler for tiotropium on factors other than efficacy or safety. These could be patient preference for a particular inhaler, ease of use and the efficiency of drug delivery, with the aim of optimizing adherence and clinical outcomes with long-term tiotropium maintenance therapy.