1. Tiotropium is noninferior to salmeterol in maintaining improved lung function in B16-Arg/Arg patients with asthma;Bateman;Journal of Allergy and Clinical Immunology,2011
2. NCT00350207 A 16-week randomised, placebo-controlled, double-blind, double-dummy, parallel-group study comparing the efficacy and safety of tiotropium inhalation solution delivered by the Respimat Inhaler (2 actuations of 2.5 mcg once daily) with that of salmeterol from the hydrofluoroalkane metered dose inhaler (2 actuations of 25 mcg twice daily) in moderate persistent asthma patients with the B16-Arg/Arg genotype clinicaltrials.gov/show/NCT00350207
3. Tiotropium bromide in asthma patients: an alternative to inhaled long-acting beta-agonists?;Lane;Journal of the Royal College of Physicians of Edinburgh,2010
4. NCT00565266 Asthma Clinical Research Network (ACRN) Trial - Tiotropium bromide as an alternative to increased inhaled corticosteroid in patients inadequately controlled on a lower dose of inhaled corticosteroid (TALC) clinicaltrials.gov/show/NCT00565266
5. Predictors of response to tiotropium versus salmeterol in asthmatic adults;Peters;Journal of Allergy and Clinical Immunology,2013