In moderate and severe asthma, the use of inhaled corticosteroid (ICS)/formoterol maintenance and reliever therapy (MART) reduces the risk of severe exacerbation by about one-third compared with the equivalent dose of ICS/long-acting beta2-agonist (LABA) maintenance plus short-acting beta2-agonist (SABA) reliever therapy.1 This efficacy has not only been demonstrated in populations with tightly defined asthma,1 but also in a high-risk ‘real-world’ population with asthma, which included smokers, and did not require the demonstration of bronchodilator responsiveness.2 The broad population of patients with asthma to whom ICS/formoterol MART is now prescribed is likely to include a substantive proportion who also have clinical characteristics of chronic obstructive pulmonary disease (COPD), previously referred to as the asthma–COPD overlap syndrome.3 Asthma and COPD share many clinical and pathophysiological features,4 and long-standing asthma is a strong risk factor for the development of COPD.5 This leads to the question as to whether the ICS/formoterol MART regimen might also have a favourable risk/benefit profile in COPD.

This issue has been addressed for the first time by Muiser et al,6 who report the findings of a randomised controlled trial (RCT) comparing budesonide/formoterol prescribed according to the MART regimen with double the equivalent ICS dose …