Tiotropium Respimat Is Effective for the Treatment of Asthma at a Dose Lower Than That for Chronic Obstructive Pulmonary Disease.

Anticholinergic drug products are not part of the current treatment paradigm for asthma, despite their widespread availability for chronic obstructive pulmonary disease (COPD) and interest in their use for asthma. Published study results, mostly of short duration and primarily with ipratropium and tiotropium, have revealed inconsistent efficacy results. Consequently, the role of inhaled anticholinergic drugs in the treatment of asthma has been unclear. This commentary discusses and comments on data from five clinical trials in adults that were submitted by Boehringer Ingelheim to the U.S. Food and Drug Administration to support approval of tiotropium delivered by the Respimat device (Spiriva Respimat) for the treatment of asthma. These trials provided substantial evidence that supported the approval of Spiriva Respimat at a recommended dose of 2.5 μg once daily for asthma. Notably, in trials that evaluated two doses of tiotropium, 2.5 μg and 5 μg (the dose approved for COPD), pulmonary function measures for Spiriva Respimat 2.5 μg once daily were better overall than those obtained for the 5-μg once-daily dose, thus justifying selection of the lower dose for asthma. Spiriva Respimat represents the first new class of drug approved by the U.S. Food and Drug Administration for the treatment of asthma in more than a decade. The availability of Spiriva Respimat for asthma along with other novel therapies currently under development has the potential to impact asthma treatment guidelines.