Tiotropium Respimat® add-on therapy to inhaled corticosteroids in patients with symptomatic asthma improves clinical outcomes regardless of baseline characteristics

Up to half of people with asthma still suffer from symptoms despite treatment. A drug that relaxes the smooth muscle in the airways, called tiotropium, reduces symptoms of asthma when it is added on top of other asthma drugs. Asthma patients are diverse. We wanted to see whether the drug works across different patients. To test this, we studied just over 1500 people with symptomatic moderate asthma. Some were given the drug tiotropium at one dose (5 μg) and some were given the drug at a lower dose (2.5 μg), once a day, on top of other asthma drugs. Other patients were given a placebo (a substance with no effect) or a drug called salmeterol, but here we focus on the tiotropium and placebo groups. We measured their symptoms and breathing before and after giving them the different drugs. We found that tiotropium improves asthma symptoms and control compared with the placebo across the different patient types.