Comparative studies of dual bronchodilation in COPD

Asthma and COPD: A Focus on β-Agonists - Past, Present and Future

Asthma has been recognised as a respiratory disorder for millennia and the focus of targeted drug development for the last 120 years. Asthma is one of the most common chronic non-communicable diseases worldwide. Chronic obstructive pulmonary disease (COPD), a leading cause of morbidity and mortality worldwide, is caused by exposure to tobacco smoke and other noxious particles and exerts a substantial economic and social burden. This chapter reviews the development of the treatments of asthma and COPD particularly focussing on the β-agonists, from the isolation of adrenaline, through the development of generations of short- and long-acting β-agonists. It reviews asthma death epidemics, considers the intrinsic efficacy of clinical compounds, and charts the improvement in selectivity and duration of action that has led to our current medications. Important β2-agonist compounds no longer used are considered, including some with additional properties, and how the different pharmacological properties of current β2-agonists underpin their different places in treatment guidelines. Finally, it concludes with a look forward to future developments that could improve the β-agonists still further, including extending their availability to areas of the world with less readily accessible healthcare.

Dual bronchodilation for the treatment of COPD - From bench to bedside

Because there is a solid pharmacological rationale based on positive interactions between long-acting muscarinic receptor antagonists (LAMAs) and long-acting β-agonists (LABAs) for their ability to relax human airway smooth muscle in vitro alongside several randomised controlled trials (RCTs) and real-world observational studies that support the use of LAMA/LABA fixed-dose combinations (FDCs) for the treatment of patients with COPD, in this narrative review we discuss the preclinical and clinical proofs supporting the use of LAMA+LABA therapy in COPD and why this therapeutic approach optimises bronchodilation. Robust evidence indicates that all LAMA/LABA FDCs are consistently more effective than LAMA or LABA administered alone in improving lung function, dyspnoea, quality of life, and exercise capacity in patients with COPD. However, the ability of dual bronchodilation with FDCs of LAMA/LABA to prevent or reduce the risk of COPD exacerbations remains unclear due to conflicting data from large RCTs, despite several mechanisms explaining why such combinations should be of value in decreasing the frequency of COPD exacerbations. Both LABAs and LAMAs mechanistically can affect the cardiovascular system, but from clinical studies to date, LAMA/LABA FDCs have an acceptable cardiovascular safety profile, at least in the COPD population enrolled in RCTs. Indirect evidence suggests that some FDCs may even exert a protective role against serious cardiovascular adverse events compared to monotherapies. Consequently, several LAMA/LABA FDCs have been developed and approved for clinical use as treatments for patients with COPD. However, to date, there are unfortunately very few head-to-head studies comparing the safety and efficacy of different LAMA/LABA FDCs making it difficult to choose the most appropriate combination, although the use of meta-analyses has provided some information in this regard.