Phase 3 Trial Update of Tiotropium for Asthma Patients Symptomatic Despite ICS/LABA Treatment

Boehringer Ingelheim announced results from its Phase 3 PrimoTinA-asthma studies, evaluating tiotropium delivered by the Respimat Soft Mist Inhaler (SMI) in adults with asthma who remain symptomatic despite treatment with at least inhaled corticosteroids (ICS)/long-acting beta-agonists (LABA).

The PrimoTinA-asthma studies (part of the ongoing Phase 3 trial program named UniTinA-asthma) were two replicate double-blind parallel-group trials. Patients enrolled in the studies had a post-bronchodilator FEV1 <80% predicted and Asthma Control Questionnaire 7 (ACQ-7) score ≥1.5, while on at least high dose ICS/LABA. A total of 912 patients were randomized to additional once-daily tiotropium Respimat 5mcg or placebo for 48 weeks.

The pre-specified co-primary lung function endpoints included peak and trough FEV1 at 24 weeks. Adding tiotropium Respimat provided significant lung function improvements at 24 weeks, which were sustained over 48 weeks.

For the third co-primary endpoint, in the pre-specified combined analysis of the two trials, the addition of tiotropium Respimat was associated with an increase in time to first severe asthma exacerbation (282 days vs. 226 days with placebo, as measured in the first quartile of patients.) This corresponds to a 21% relative risk reduction in numbers of patients with at least one severe exacerbation ([HR, 0.79; 95% CI 0.62–1; P=0.03] ARR 5.9% (26.9% vs. 32.8%)).

Further pre-specified secondary endpoints showed that the addition of tiotropium Respimat increased the time to first exacerbation of asthma (315 days, vs. 181 days with placebo) and a relative risk reduction of 31% of patients having any asthma exacerbation ([HR,0.69; 95% CI, 0.58–0.82; P<0.001] ARR 13.3% (49.9% vs. 63.2%)).

Tiotropium is a long-acting muscarinic antagonist (LAMA) that works by opening narrowed airways by targeting a dominant reversible mechanism - cholinergic bronchoconstriction and helping to keep them open for 24 hours with once-daily dosing. Marketed as Spiriva Handihaler, tiotropium is indicated for the treatment of chronic obstructive pulmonary disorder (COPD) symptoms. Respimat SMI is an innovative delivery device, which uses mechanical energy (a spring) to generate a long-lasting, slow-moving mist for inhalation.

For more information call (800) 542-6257 or visit www.boehringer-ingelheim.com.