Introduction: It has long been known that combining short-acting muscarinic antagonists and β2 agonists produces additive effects on the lung function of patients with chronic obstructive pulmonary disease (COPD). Two closely related approaches to provide long-acting treatments offering the same functional are compared.
Areas covered: Six combinations of long-acting muscarinic antagonists and β2 agonists are in clinical development, with five having progressed to Phase III studies or regulatory filing. Two dual-acting muscarinic antagonist/β2 agonist molecules have progressed to Phase II clinical studies, with two more having been identified as in clinical development.
Expert opinion: Both approaches have been shown to provide clinically enhanced bronchodilator activity that is superior to that offered by the current standard treatments, but clinical results have yet to clearly demonstrate that these new combinations also provided an enhanced reduction in the frequency of disease exacerbations. At least one of these combinations should reach the market in 2014, so by the end of 2015, it should be clear how useful such combinations may be in the treatment of COPD.