BACKGROUND: Despite currently available therapies and detailed treatment guidelines, many patients with asthma remain symptomatic. Tiotropium delivered by the soft mist inhaler Respimat®, as add-on therapy to medium-dose inhaled corticosteroids (ICS), has been shown to improve lung function and asthma control in patients with symptomatic moderate asthma.
OBJECTIVE: To determine whether the efficacy of tiotropium Respimat® in asthma differs by patients' study baseline characteristics.
METHODS: Two replicate Phase III, randomized, double-blind, placebo-controlled, parallel-group studies (MezzoTinA-asthma®; NCT01172808 and NCT01172821) of once-daily tiotropium Respimat 5 μg and 2.5 μg add-on to ICS were conducted in patients with symptomatic asthma despite treatment with medium-dose ICS with or without additional controllers. Subgroup analyses of peak forced expiratory volume in 1 s (FEV1), trough FEV1, risk of severe asthma exacerbation and Asthma Control Questionnaire responder rate were performed to determine whether results were influenced by patients' baseline characteristics.
RESULTS: In this analysis, 523 patients received placebo while 517 and 519 patients received the 5 μg and 2.5 μg dose of tiotropium Respimat, respectively. The magnitude of the improvements in lung function and asthma control, as well as the reduced risk of severe exacerbation with both doses of tiotropium Respimat versus placebo, was independent of a broad range of baseline characteristics.
CONCLUSIONS: Once-daily tiotropium Respimat as add-on to ICS is a beneficial treatment option for patients with asthma who remain symptomatic despite at least medium-dose ICS, regardless of baseline characteristics.