“Treatable traits” have been proposed as a new paradigm for the management of airway diseases, particularly complex disease, which aims to apply personalised medicine to each individual to improve outcomes. Moving new treatment approaches from concepts to practice is challenging, but necessary. In an effort to accelerate progress in research and practice relating to the treatable traits approach, the Treatable Traits Down Under International Workshop was convened in Melbourne, Australia in May 2018. Here, we report the key concepts and research questions that emerged in discussions during the meeting. We propose a programme of research that involves gaining international consensus on candidate traits, recognising the prevalence of traits, and identifying a potential hierarchy of traits based on their clinical impact and responsiveness to treatment. We also reflect on research methods and designs that can generate new knowledge related to efficacy of the treatable traits approach and consider multidisciplinary models of care that may aid its implementation into practice.

Chronic obstructive pulmonary disease (COPD) frequently coexists with other conditions often known as comorbidities. The prevalence of most of the common comorbid conditions that accompany COPD has been widely reported. It is also recognized that comorbidities have significant health and economic consequences. Nevertheless, there is scant research examining how comorbidities should be assessed and managed in the context of COPD. Also, the underlying mechanisms linking COPD with its comorbidities are still not fully understood. Owing to these knowledge gaps, current disease‐specific approaches provide clinicians with little guidance in terms of managing comorbid conditions in the clinical care of multi‐diseased COPD patients. This review discusses the concepts of comorbidity and multi‐morbidity in COPD in relation to the overall clinical outcome of COPD management. It also summarizes some of the currently available clinical scores used to measure comorbid conditions and their prognostic abilities. Furthermore, recent developments in the proposed mechanisms linking COPD with its comorbidities are discussed.

Asthma treatment goals currently focus on symptom and exacerbation control rather than remission. Remission is not identical to cure, but is a step closer. This review considers the current definitions of remission in asthma, the prevalence and predictors, the pathophysiology of remission, the possibility of achieving it using the available treatment options, and the future research directions. Asthma remission is characterised by a high level of disease control, including the absence of symptoms and exacerbations, and normalisation or optimisation of lung function with or without ongoing treatment. Even in those who develop a symptomatic remission of asthma, persistent pathological abnormalities are common, leading to a risk of subsequent relapse at any time. Complete remission requires normalisation or stabilisation of any underlying pathology in addition to symptomatic remission. Remission is possible as part of the natural history of asthma, and the prevalence of remission in the adult asthma population varies between 2% and 52%. The factors associated with remission include mild asthma, better lung function, better asthma control, younger age, early-onset asthma, shorter duration of asthma, milder bronchial hyperresponsiveness, fewer comorbidities and smoking cessation or never smoking. Although previous studies have not targeted treatment-induced remission, there is some evidence to show that the current long-term add-on therapies such as biologics and azithromycin can achieve some criteria for asthma remission on treatment, at least in a subgroup of patients. However, more research is required. Long-term remission could be included as a therapeutic goal in studies of asthma treatments.

Rationale: Treatable traits have been proposed as a new paradigm for airway disease management.Objectives: To characterise treatable traits in a severe asthma population and to determine the efficacy of targeting treatments to these treatable traits in severe asthma.Methods: Participants (n=140) with severe asthma were recruited to a cross-sectional study and underwent a multidimensional assessment to characterise treatable traits. Eligible participants with severe asthma (n=55) participated in a 16-week parallel-group randomised controlled trial to determine the feasibility and efficacy of management targeted to predefined treatable traits, compared to usual care in a severe asthma clinic. The patient-reported outcome of health-related quality of life was the trial's primary end-point.Main results: Participants with severe asthma had a mean±sdof 10.44±3.03 traits per person, comprising 3.01±1.54 pulmonary and 4.85±1.86 extrapulmonary traits and 2.58±1.31 behavioural/risk factors. Individualised treatment that targeted the traits was feasible and led to significantly improved health-related quality of life (0.86 units, p<0.001) and asthma control (0.73, p=0.01).Conclusions: Multidimensional assessment enables detection of treatable traits and identifies a significant trait burden in severe asthma. Targeting these treatable traits using a personalised-medicine approach in severe asthma leads to improvements in health-related quality of life, asthma control and reduced primary care acute visits. Treatable traits may be an effective way to address the complexity of severe asthma.