Although the goal of asthma management is to achieve and maintain control of asthma symptoms, prospective studies have confirmed that a significant proportion of patients do not achieve this target, even after upward titration of an inhaled corticosteroid (ICS) plus a long-acting β2-agonist (LABA).1, 2 The last recommended step in the Global Initiative for Asthma (GINA) guidelines is the addition of another treatment, such as antileukotrienes, theophyllines, anti-IgE, and immunosuppressants (eg, systemic corticosteroids or cyclosporine). Nevertheless, many patients remain both symptomatic and obstructed.2 A potential alternative approach is the addition of a second bronchodilator with an alternative mode of action, the anticholinergic tiotropium bromide, which has been shown to be effective in patients with chronic obstructive pulmonary disease (COPD), in whom it is widely used.3, 4