The efficacy of tiotropium administered via Respimat® Soft Mist™ Inhaler or HandiHaler® in COPD patients

SummaryBackgroundTiotropium, a once daily inhaled anticholinergic delivered via HandiHaler®, provides bronchodilation for >24 h and improves patient-centred outcomes. The Respimat® Soft Mist™ Inhaler (SMI), a novel, propellant-free inhaler, has been developed and proposed as an alternative delivery device for use with tiotropium.MethodsIn a pre-specified, pooled analysis of two 30-week, double-blind, double-dummy, crossover studies, 207 patients with Chronic Obstructive Pulmonary Disease (COPD) were randomised to receive once daily tiotropium 5 μg or 10 μg (aqueous solution delivered via Respimat SMI), tiotropium 18 μg (inhalation powder via HandiHaler) or placebo. The primary endpoint was trough forced expiratory volume in 1 s (FEV1) response. Forced vital capacity (FVC), peak expiratory flow rate (PEFR), rescue medication use, safety and pharmacokinetics (in a subgroup of patients) were also assessed.ResultsBoth tiotropium doses delivered by Respimat SMI were significantly superior to placebo and non-inferior to tiotropium 18 μg HandiHaler on the primary endpoint (all p < 0.0001). All active treatments were significantly superior to placebo (all p < 0.0001) and both doses of tiotropium Respimat SMI were non-inferior to tiotropium 18 μg HandiHaler on the secondary spirometry variables and rescue medication use. The systemic exposure was similar between tiotropium 5 μg Respimat SMI and tiotropium 18 μg HandiHaler but was higher for tiotropium 10 μg Respimat SMI. All active treatments were well tolerated.ConclusionsTiotropium 5 μg Respimat SMI is comparable with tiotropium 18 μg HandiHaler in terms of efficacy, pharmacokinetics and safety. Respimat SMI is an effective alternative, multi-dose delivery device for tiotropium.