Tiotropium, a once-daily long-acting anticholinergic agent, has been shown to be an efficacious and safe add-on treatment for adults with symptomatic asthma, despite treatment with inhaled corticosteroids (ICS). A large proportion of asthmatic adolescents have symptomatic disease despite a wide range of therapeutic options. We investigated the efficacy and safety of three doses of tiotropium, administered in the evening (via Respimat^® SoftMist™ inhaler), versus placebo in asthmatic adolescents symptomatic despite ICS treatment.

This randomised, double-blind, placebo-controlled, incomplete crossover study evaluated once-daily tiotropium 5 μg, 2.5 μg and 1.25 μg versus placebo in three 4-week treatment periods. Primary efficacy end point was change in peak forced expiratory volume in 1 s within 3 h post-dose from baseline (peak FEV_1(0–3h)).

From 139 enrolled patients, 105 were randomised to receive one of four treatment sequences. Peak FEV_1(0–3h) response for tiotropium 5 μg was significantly greater versus placebo (p = 0.0043). Trough FEV₁ responses were significantly greater for tiotropium 5 μg (p < 0.00001) and 1.25 μg (p = 0.0134) versus placebo, but not for 2.5 μg (p = 0.0975), while FEV₁ area under the curve_(0–3h) responses were significant for all doses (p = 0.00001–0.0398). Overall incidence of adverse events was balanced across treatment groups, with no dose-dependent observations. The majority of adverse events were mild to moderate in intensity.

This first study of tiotropium in adolescents with symptomatic asthma demonstrates that tiotropium is well tolerated and efficacious as add-on to maintenance treatment with ICS.

ClinicalTrials.gov identifier; NCT01122680.