Positioning of Long-Acting Muscarinic Antagonists in the Management of Asthma

Abstract

Despite a range of efficacious therapies for asthma, including inhaled corticosteroids (ICS) and long-acting β₂-agonists (LABA), a significant proportion of patients have poor asthma control and retain a risk of future worsening of their symptoms. Long-acting muscarinic antagonist (LAMA) bronchodilators offer a well-tolerated, efficacious, and cost-effective add-on to a patient's treatment. Of the LAMAs currently under investigation or available for the treatment of asthma, evidence from a comprehensive clinical trial program in adults and children shows that once-daily treatment with tiotropium provides benefits for patients with uncontrolled asthma despite the use of ICS and LABAs. Tiotropium is included in the Global Initiative for Asthma (GINA) strategy document as an add-on therapy option for patients at Step 4 or 5 with a history of asthma exacerbations. Tiotropium Respimat® has demonstrated safety and efficacy in patients with a range of disease severities, ages, and phenotypes. This review describes the evidence for the use of LAMA as add-on therapy for patients with asthma who remain uncontrolled despite the use of ICS and LABA treatments.

Keywords: Asthma; long-acting muscarinic antagonists; tiotropium.

Figure. The role of cholinergic activity in the pathophysiology of asthma. Autonomic regulation of airway smooth muscle tone. M₁, M₂, M₃ represent muscarinic receptors 1, 2, and 3. + and − symbols represent signals increasing and decreasing airway smooth muscle tone, respectively. Reproduced with permission from Price et al. M, muscarinic.