Laird Harrison

March 06, 2014

SAN DIEGO — Patients with mild asthma using corticosteroids can improve their lung function by inhaling tiotropium, a phase 3 clinical trial suggests.

"Starting the first day, tiotropium improved lung function," Georges El Azzi, MD, from Boehringer Ingelheim, told Medscape Medical News.

Dr. Azzi presented the findings here at the American Academy of Allergy, Asthma & Immunology 2014.

This study of mild asthma follows previous trials showing that tiotropium can improve symptoms of moderate and severe asthma. All 3 trials used Boehringer Ingelheim's Respimat inhaler to deliver the tiotropium.

Tiotropium is a long-acting anticholinergic bronchodilator and a selective M3 muscarinic-receptor agonist. The drug is currently approved in the United States to treat chronic obstructive pulmonary disease.

Dr. Azzi said his team thought tiotropium might complement inhaled corticosteroids and help patients whose asthma is not completely controlled with current therapies.

To see whether inhaled tiotropium could improve symptoms in patients with mild asthma who are already using steroids, the researchers randomly assigned 155 patients to inhale 5.0 µg/day, 154 to inhale 2.5 µg/day, and 155 to inhale a placebo.

Patients in the treatment groups started with a baseline forced expiratory volume in the first second of exhaling (FEV1) of 2.3 L; those in the placebo group started with a FEV1 of 2.2 L.

The researchers measured the change in FEV1 after 12 weeks of treatment over a 3-hour period.

Improvement was significantly greater in the tiotropium groups than in the placebo group.

Table. Change at 12 Weeks Compared With Placebo

Response by Dose Adjusted Mean Difference (mL) P Value
3-h peak FEV1    
5 µg 128 .0005
2.5 µg 159 <.0001
Trough FEV1    
5 µg 122 .001
2.5 µg< 110 .0028


Improvement in morning and evening peak expiratory flow after 12 weeks was significantly greater in the treatment groups than in the placebo group.

Patients in the 5 µg group also showed more improvement in peak and trough forced vital capacity, but those in the 2.5 µg group did not.

All of the groups showed improvement on the Asthma Control Questionnaire, but the differences were not significant among the groups.

The addition of tiotropium appeared to be fairly safe; the incidence of adverse events was similar in the 2 treatment and the placebo groups.

Another group of researchers at the meeting, also supported by Boehringer Ingelheim, presented analyses of their previous data on tiotropium in patients taking inhaled corticosteroids for moderate and severe asthma.

One analysis showed that patients with moderate asthma could benefit from tiotropium, regardless of their T-helper cell type 2 inflammatory status.

Another analysis showed that patients with severe asthma could benefit from tiotropium in addition to inhaled corticosteroids, along with long-acting beta agonists, and independent of whether they received leukotriene-receptor agonists at baseline.

The results look promising, said Heather Dyer, MD, a Dallas allergist, who chatted with the presenters at their poster session.

"I think it's good, but there is a lot more coming onto the market and it's going to be hard to say which drug is best for which patient," she told Medscape Medical News.

Even drug companies have trouble giving clear guidelines, she explained.

The new therapy presents clinicians and their patients with another challenge, Dr. Dyer noted: "Making sure it's covered."

The studies were funded by Boehringer Ingelheim. Dr. Azzi is an employee of the company. Dr. Dyer has disclosed no relevant financial relationships.

American Academy of Allergy, Asthma & Immunology (AAAAI) 2014: Abstract 15. Presented March 1, 2014.


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