Tiotropium Respimat Add-on Is Efficacious in Symptomatic Asthma, Independent of T2 Phenotype

An update on long-acting muscarinic agents for asthma therapy

INTRODUCTION

The manifestations of asthma are influenced by the dysfunction of the autonomic nervous system, which results in elevated vagal tone within the airways. Acetylcholine (ACh) plays a pivotal role in the pathophysiology of asthma through its interaction with muscarinic acetylcholine receptors (mAChRs). Consequently, using mAChR antagonists to counteract the actions of ACh is scientifically sound.

AREAS COVERED

This narrative review methodically examines the latest information on the mechanisms and evidence supporting the use of long-acting muscarinic antagonists (LAMAs) in asthma.

EXPERT OPINION

Adding a LAMA to existing asthma treatments involving an ICS and a LABA, within a single inhaler triple therapy (SITT), improves lung function regulating airflow limitation, reduces exacerbations, and eosinophilic inflammation and offers a more comprehensive approach to managing inflammation and tissue remodeling, which are linked to ACh. Additionally, it disrupts the vicious cycle of ACh release that contributes to neuronal plasticity and dysfunction of small airways. Identifying treatable traits is key to using SITT in a customized way that aligns with patients' needs. The 5T (Triple Therapy Targeting Treatable Traits) approach proposes the utilization of SITT for all asthma cases, not solely severe ones, and involves using LAMAs in ICS/LABA combinations earlier than current guidelines recommend.

The role of ILC2s in asthma combined with atopic dermatitis: bridging the gap from research to clinical practice

Asthma, a complex and heterogeneous respiratory disease, is often accompanied by various comorbidities, notably atopic dermatitis (AD). AD characterized by recurrent eczematous lesions and severe itching, can trigger or exacerbate asthma. Individuals with AD are 2.16 times more likely to develop asthma compared to the reference population. Furthermore, asthmatics with AD experience more severe and frequent emergency department visits and hospital admissions compared to patients with asthma alone. The close connection between asthma and AD indicates there are overlap pathophysiologic mechanisms. It is well-known that dysregulated type 2 (T2) immune inflammation is pivotal in the development of both AD and asthma, traditionally attributed to CD4+ type 2 helper T (Th2) cells. Over the past decade, group 2 innate lymphoid cells (ILC2s), as potent innate immune cells, have been demonstrated to be the key drivers of T2 inflammation, playing a crucial role in the pathogenesis of both asthma and AD. ILC2s not only trigger T2 immune-inflammation but also coordinate the recruitment and activation of innate and adaptive immune cells, thereby intensifying the inflammatory response. They are rapidly activated by epithelium alarmins producing copious amounts of T2 cytokines such as interleukin (IL) -5 and IL-13 that mediate the airway inflammation, hyperresponsiveness, and cutaneous inflammation in asthma and AD, respectively. The promising efficiency of targeted ILC2s in asthma and AD has further proven their essential roles in the pathogenesis of both conditions. However, to the best of our knowledge, there is currently no review article specifically exploring the role of ILC2s in asthma combined with AD and their potential as future therapeutic targets. Hence, we hypothesize that ILC2s may play a role in the pathogenesis of asthma combined with AD, and targeting ILC2s could be a promising therapeutic approach for this complex condition in the future. In this review, we discuss recent insights in ILC2s biology, focus on the current knowledge of ILC2s in asthma, AD, particularly in asthma combined with AD, and suggest how this knowledge might be used for improved treatments of asthma combined with AD.

Asthma Phenotypes and Biomarkers

Asthma experienced by both adults and children is a phenotypically heterogeneous condition. Severe asthma, characterized by ongoing symptoms and airway inflammation despite high doses of inhaled and/or systemic corticosteroids, is the focus of research efforts to understand this underlying heterogeneity. Clinical phenotypes in both adult and pediatric asthma have been determined using supervised definition-driven classification and unsupervised data-driven clustering methods. Efforts to understand the underlying inflammatory patterns of severe asthma have led to the seminal discovery of type 2-high versus type 2-low phenotypes and to the development of biologics targeted at type 2-high inflammation to reduce the rates of severe asthma exacerbations. Type 2-high asthma is characterized by upregulation of T helper 2 immune pathways including interleukin (IL)-4, IL-5, and IL-13 along with eosinophilic airway inflammation, sometimes allergic sensitization, and responsiveness to treatment with corticosteroids. Type 2-low asthma is poorly responsive to corticosteroids and is not as well characterized as type 2-high asthma. Type 2-low asthma is limited by being defined as the absence of type 2-high inflammatory markers. Choosing a biologic for the treatment of severe asthma involves the evaluation of a panel of biomarkers such as blood eosinophils, total and specific immunoglobulin E/allergic sensitization, and fractional exhaled nitric oxide. In this review, we focus on the underlying pathobiology of adult and pediatric asthma, discuss the different phenotype-based treatment options for adult and pediatric type 2-high with or without allergic asthma and type 2-low asthma, and describe a clinical phenotyping approach to patients to guide out-patient therapy. Finally, we end with a discussion of whether pediatric asthma exacerbations necessitating admission to an ICU constitute their own high-risk phenotype and/or whether it is a part of other previously defined high-risk subgroups such as difficult-to-control asthma, exacerbation-prone asthma, and severe treatment-resistant asthma.

The Bronchodilator and Anti-Inflammatory Effect of Long-Acting Muscarinic Antagonists in Asthma: An EAACI Position Paper

As cholinergic innervation is a major contributor to increased vagal tone and mucus secretion, inhaled long-acting muscarinic antagonists (LAMA) are a pillar for the treatment of chronic obstructive pulmonary disease and asthma. By blocking the muscarinic receptors expressed in the lung, LAMA improve lung function and reduce exacerbations in asthma patients who remained poorly controlled despite treatment with inhaled corticosteroids and long-acting β2 agonists. Asthma guidelines recommend LAMA as a third controller to be added on before the initiation of biologicals. In addition to bronchodilation, LAMA also exert anti-inflammatory and anti-fibrotic effects by inhibiting muscarinic receptors present in neutrophils, macrophages, fibroblasts and airway smooth muscle cells. Thus, besides bronchodilation, LAMA might provide additional therapeutic effects, thereby supporting an endotype-driven approach to asthma management. The Position Paper, developed by the Asthma Section of the European Academy of Allergy and Clinical Immunology, discusses the main cholinergic pathways in the lung, reviews the findings of significant clinical trials and real-life studies on LAMA use in asthma, examines the placement of these drugs in asthma clinical guidelines, and considers the potential for personalised medicine with LAMA in both adult and paediatric asthma patients.

The use of a long-acting muscarinic antagonist in the treatment of asthma: A tertiary asthma center experience

INTRODUCTION

We aimed to investigate the frequency and sociodemographic and clinical distinguishing features of asthmatic patients in whom long-acting muscarinic antagonists (LAMA) were added to maintenance therapy in our clinic.

METHODS

In this cross-sectional study, data on sociodemographic, phenotypic, and clinical characteristics of patients with asthma using Steps 4 and 5 medications, who were followed up in our center for at least 1 year, were obtained from file records. Whether the patients received add-on LAMA for at least 6 months was also noted.

RESULTS

A total of 279 patients with asthma using Steps 4 and 5 medications (female/male: 215/64) with a mean age of 50.84 ± 12.42 years were included in the study. Seventy-nine (28.3%) patients (female/male: 60/19) with a mean age of 52.45 ± 11.61 years used LAMA as an add-on treatment; 28 (37.8%) at Step 4 and 51 (24.8%) at Step 5. In Steps 4 and 5, there was no difference in terms of age, sex, body mass index, smoking status, being allergic or eosinophilic, phenotype, and asthma onset between patients with and without add-on LAMA. Asthma control in the previous year was better, and minimum forced expiratory volume in 1s (FEV1) was lower in patients with LAMA than in those without in Step 4 (P = 0.001 and P = 0.030, respectively). In Step 5, the rate of being well-controlled was higher in those without add-on LAMA (P < 0.001). The number of exacerbations in the previous year was higher, and minimum and maximum FEV1 were lower in patients with add-on LAMA (P < 0.001 and P < 0.001, respectively).

CONCLUSION

Our study showed that add-on LAMA treatment was effective in increasing asthma control in patients using Step 4 medication independent of baseline characteristics and asthma phenotype.

Nasal epithelial gene expression and total IgE in children and adolescents with asthma

BACKGROUND

Little is known about nasal epithelial gene expression and total IgE in youth.

OBJECTIVE

We aimed to identify genes whose nasal epithelial expression differs by total IgE in youth, and group them into modules that could be mapped to airway epithelial cell types.

METHODS

We conducted a transcriptome-wide association study of total IgE in 469 Puerto Ricans aged 9 to 20 years who participated in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study, separately in all subjects and in those with asthma. We then attempted to replicate top findings for each analysis using data from 3 cohorts. Genes with a Benjamini-Hochberg-adjusted P value of less than .05 in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study and a P value of less than .05 in the same direction of association in 1 or more replication cohort were considered differentially expressed genes (DEGs). DEGs for total IgE in subjects with asthma were further dissected into gene modules using coexpression analysis, and such modules were mapped to specific cell types in airway epithelia using public single-cell RNA-sequencing data.

RESULTS

A higher number of DEGs for total IgE were identified in subjects with asthma (n = 1179 DEGs) than in all subjects (n = 631 DEGs). In subjects with asthma, DEGs were mapped to 11 gene modules. The top module for positive correlation with total IgE was mapped to myoepithelial and mucus secretory cells in lower airway epithelia and was regulated by IL-4, IL5, IL-13, and IL-33. Within this module, hub genes included CDH26, FETUB, NTRK2, CCBL1, CST1, and CST2. Furthermore, an enrichment analysis showed overrepresentation of genes in signaling pathways for synaptogenesis, IL-13, and ferroptosis, supporting interactions between interleukin- and acetylcholine-induced responses.

CONCLUSIONS

Our findings for nasal epithelial gene expression support neuroimmune coregulation of total IgE in youth with asthma.

Efficacy of mometasone/indacaterol/glycopyrronium in patients with inadequately controlled asthma with respect to baseline eosinophil count: Post hoc analysis of IRIDIUM study

BACKGROUND

Baseline characteristics could potentially guide asthma treatments. We evaluated whether baseline eosinophil levels affect the efficacy of mometasone/indacaterol/glycopyrronium (MF/IND/GLY) in patients with inadequately controlled asthma.

METHOD

In this post hoc analysis of IRIDIUM study, efficacy of high-dose MF/IND/GLY (160/150/50 μg, once-daily [o.d.]) versus high-dose MF/IND (320/150 μg o.d.) and high-dose fluticasone/salmeterol (FLU/SAL [500/50 μg, twice-daily [b.i.d.]); and efficacy of pooled MF/IND/GLY (160/150/50 μg and 80/150/50 μg) versus pooled MF/IND (320/150 μg and 160/150 μg) was evaluated in patient subgroups with baseline blood eosinophil count of <300 cells/μL or ≥300 cells/μL.

RESULTS

Overall, 3065 patients were included. At Week 26, high-dose MF/IND/GLY showed improved trough FEV1 versus high-dose MF/IND (Δ78mL [<300 cells/μL]; Δ54mL [≥300 cells/μL]) and FLU/SAL (Δ112mL [<300 cells/μL]; Δ98mL [≥300 cells/μL]). Similarly, pooled MF/IND/GLY also showed improved trough FEV1 versus pooled MF/IND (Δ75mL [<300 cells/μL]; Δ68mL [≥300 cells/μL]). Over 52 weeks, high-dose MF/IND/GLY reduced the annualized rate of moderate or severe asthma exacerbations by 23% and 10%, severe exacerbations by 31% and 15%, and all exacerbation by 33% and 10% versus high-dose MF/IND for subgroups with <300 cells/μL and ≥300 cells/μL, respectively; and by 33% and 41%, 45% and 42%, 42% and 39% versus FLU/SAL, respectively. Similarly, pooled MF/IND/GLY reduced exacerbations by 22% and 8%, 21% and 7%, 27% and 8%, versus pooled MF/IND, for the respective subgroups.

CONCLUSION

MF/IND/GLY showed improvement in lung function and reduction in asthma exacerbations over MF/IND and FLU/SAL independent of baseline eosinophil levels, indicating that eosinophil levels did not affect the efficacy of MF/IND/GLY in patients with inadequately controlled asthma.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02571777 (IRIDIUM).

Open-inhaler versus single-inhaler triple therapy (long-acting muscarinic antagonist, inhaled corticosteroid, and long-acting β2-agonist) in asthma patients: a narrative review

OBJECTIVE

To review the evidence for the use of open-inhaler (inhaled corticosteroid [ICS] plus long-acting β2-agonist [LABA] with separate add-on long-acting muscarinic antagonist [LAMA]) versus single-inhaler triple therapy (ICS/LABA/LAMA combination) and the merits of add-on LAMA to ICS/LABA in patients with uncontrolled asthma.

DATA SOURCES

Original research articles were identified from PubMed using the search term "triple therapy asthma." Information was also retrieved from the ClinicalTrials.gov website.

STUDY SELECTIONS

Articles detailing the use of add-on LAMA to ICS plus LABA (open-inhaler triple therapy), and closed triple therapy compared with ICS plus LABA dual therapy, addressing patient symptoms, exacerbations, and health-related quality of life.

RESULTS

Open-inhaler triple therapy was associated with a significantly reduced incidence of hospitalizations and emergency department visits and a decrease in ICS dose, oral corticosteroids use, and antibiotics use. Exacerbations and acute respiratory events were also reduced. Single-inhaler triple therapy showed a greater improvement in lung function, asthma control, and health status and was noninferior to open-inhaler triple therapy for Asthma Quality of Life Questionnaire scores. Single-inhaler triple therapy may also lead to improved therapy adherence.

CONCLUSION

Add-on LAMA to ICS plus LABA (open- or single-inhaler triple therapy) improves the response in patients who remain symptomatic and provides a reasonable alternative to ICS dose escalation in treatment-refractory patients.

Maintenance Therapy for Children and Adolescents with Asthma: Guidelines and Recommendations from the Emilia-Romagna Asthma (ERA) Study Group

Asthma is the most frequent chronic disease of childhood, affecting up to 20% of children worldwide. The main guidelines on asthma maintenance therapy in pediatrics suggest different approaches and describe different stages of asthma to determine the most appropriate treatment. This project aims to summarize the most recent evidence regarding maintenance therapy for asthma in children and adolescents. A multidisciplinary panel of experts was asked clinical questions regarding the treatment of children and adolescents with asthma. Overall, 10 clinical questions were addressed, and the search strategy included accessing electronic databases and a manual search of gray literature published in the last 25 years. After data extraction and narrative synthesis of results, recommendations were developed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) methodology. Results showed that the choice of medication depends on the severity of the child's asthma, phenotype, age, preference, and individual factors. In addition to medications, the identification of comorbidities and modifiable factors is crucial to obtaining good control. Asthma in children is heterogeneous, and its evolution varies over time. Since most recommendations for asthma management in childhood are extrapolated from clinical studies performed in adults, more clinical trials specifically designed for young children should be conducted.

The Role of Long-Acting Antimuscarinic Agents in the Treatment of Asthma

The journey of using anticholinergics in the treatment of asthma started with anticholinergic-containing plants such as Datura stramonium and Atropa belladonna, followed by ipratropium bromide and continued with tiotropium, glycopyrronium, and umeclidinium. Although antimuscarinics were used in the maintenance treatment of asthma over a century ago, after a long time (since 2014), it has been recommended to be used as an add-on long-acting antimuscarinic agent (LAMA) therapy in the maintenance treatment of asthma. The airway tone controlled by the vagus nerve is increased in asthma. Allergens, toxins, or viruses cause airway inflammation and inflammation-related epithelial damage, increased sensory nerve stimulation, ganglionic and postganglionic acetylcholine (ACh) release by inflammatory mediators, intensification of ACh signaling at M1 and M3 muscarinic ACh receptors (mAChRs), and dysfunction of M2 mAChR. Optimal anticholinergic drug for asthma should effectively block M3 and M1 receptors, but have minimal effect on M2 receptors. Tiotropium, umeclidinium, and glycopyrronium are anticholinergic agents with this feature. Tiotropium has been used in a separate inhaler as an add-on treatment to inhaled corticosteroid (ICS)/long-acting β2-agonist (LABA), and glycopyrronium and umeclidinium have been used in a single inhaler as a combination of ICS/LABA/LAMA in asthma in recent years. Guidelines recommend this regimen as an optimization step for patients with severe asthma before initiating any biologic or systemic corticosteroid therapy. In this review, the history of antimuscarinic agents, their effectiveness and safety in line with randomized controlled trials, and real-life studies in asthma treatment will be discussed according to the current data.

Systemic corticosteroids in asthma: A call to action from World Allergy Organization and Respiratory Effectiveness Group

Systemic corticosteroids (SCS) are a highly effective treatment for acute exacerbations and long-term symptom control in asthma. Long-term SCS use is highly prevalent across all asthma severities, occurring in over 20% of patients with severe or uncontrolled disease globally. It is now well known that exposure to both long-term and repeated acute courses of SCS is associated with a high risk of serious adverse effects (AEs), such as osteoporosis, and metabolic and cardiovascular complications, especially when prescribed onto a background of other corticosteroids. The aim of this call-to-action article, endorsed by the World Allergy Organization and the Respiratory Effectiveness Group, is to review the accumulating evidence on the burden of SCS on patients with asthma and provide an overview of potential strategies for implementing SCS Stewardship. Primary prevention of exacerbations and improvement of asthma control is a key first step in achieving SCS Stewardship, by optimizing maintenance asthma medications and addressing modifiable risk factors, such as adherence and inhaler technique. Other key elements of SCS Stewardship include increasing appropriate specialist referrals for multidisciplinary review, assessment of biomarkers, and consideration of oral corticosteroid-sparing add-on therapies (eg, biologics). In cases where SCS use is deemed clinically justified, it should be tapered to the lowest possible dose. In addition, patients receiving long-term SCS or frequent acute courses should be closely monitored for emergence of SCS-related AEs. Because of the extensive data available on the costly and burdensome AEs associated with SCS use, as well as the range of treatment options now available, there is a need for healthcare providers (HCPs) to carefully evaluate whether the benefits of SCS outweigh the potential harms, to adopt SCS-sparing and Stewardship strategies, and to consider alternative therapies where possible. Development of a structured and collaborative SCS Stewardship approach is urgently required to protect patients from the potential harm of SCS use.

Residual Dyspnea May Predict Small Airways Dysfunction and Poor Responsiveness to Single-Inhaler Triple Therapy in Asthmatic Patients

PURPOSE

Recently, single-inhaler triple therapy (SITT) has demonstrated efficacy in patients with uncontrolled asthma who were symptomatic despite treatment with inhaled corticosteroids/long-acting β2 agonists. However, the characteristics of patients who benefit from SITT remain unclear in the real-world. The aim of this study was to examine the predictors of responsiveness to SITT in patients with asthma.

PATIENTS AND METHODS

A total of 45 patients with asthma who had regularly visited our respiratory clinic and were started on SITT from March 2019 to March 2021 were retrospectively analyzed. Patients' demographic characteristics, residual respiratory symptoms, type 2 biomarkers, and lung function before SITT were assessed from the patients' medical records. Predictors of responsiveness to four-week SITT were evaluated in these patients. The definition of responders was based on the physician-assessed global evaluation of treatment effectiveness.

RESULTS

Thirty-four (75%) of 45 patients were identified as responders to SITT. Non-responders showed significantly lower forced vital capacity (FVC) (%predicted) values, and complained of dyspnea more frequently than responders before SITT (p = 0.01 and p = 0.02, respectively). There were no significant differences in demographic characteristics and type 2 biomarkers between responders and non-responders. Clinical predictors of poor response to SITT were residual dyspnea (OR = 0.14, p = 0.02), low FVC (%predicted) values (OR = 1.05, p = 0.01), and FVC (%predicted) <80% (OR = 0.11, p = 0.02). Multivariate analysis showed that poor response to SITT was associated with residual dyspnea before SITT (OR = 0.14, p = 0.02). On the other hand, patients with residual dyspnea had significantly lower FEF_25-75 (%predicted) values than patients without residual dyspnea before SITT (p = 0.04).

CONCLUSION

Residual dyspnea, reflecting small airways dysfunction, may predict poor responsiveness to short-term SITT in patients with asthma.

Recent advances in the treatment of childhood asthma: a clinical pharmacology perspective

INTRODUCTION

Childhood asthma is a complex heterogenous inflammatory disease that can pose a large burden on patients and their caregivers. There is a strong need to adapt asthma treatment to the individual patient taking into account underlying inflammatory profiles, moving from a 'one size fits all' approach toward a much-needed personalized approach.

AREAS COVERED

This review article aims to provide an overview of recent advances in the management and treatment of pediatric asthma, including novel insights on the molecular heterogeneity of childhood asthma, the emergence of biologicals to treat severe asthma, and innovative e-health and home monitoring techniques to make asthma management more convenient and accessible.

EXPERT OPINION

Molecular technologies have provided new treatment leads. E-health and home monitoring technologies have helped to gain more insights into disease dynamics and improve adherence to treatment while bringing health care to the patient. However, uncontrolled childhood asthma is still a major unmet clinical need and precision-medicine approaches are still scarce in clinical practice. Advanced omics methods may help researchers or clinicians to more accurately phenotype and treat subtypes of childhood asthma and gain more insight into the complexity of the disease.

[Markers of severity and predictors of response to treatment in severe asthma]

Asthma is a multifactorial disease with complex pathophysiology. Knowledge of its immunopathology and inflammatory mechanisms is progressing and has led to the development over recent years of increasingly targeted therapeutic strategies. The objective of this review is to pinpoint the different predictive markers of asthma severity and therapeutic response. Obesity, nasal polyposis, gastroesophageal reflux disease and intolerance to aspirin have all been considered as clinical markers associated with asthma severity, as have functional markers such as bronchial obstruction, low FEV1, small daily variations in FEV1, and high FeNO. While sinonasal polyposis and allergic comorbidities are associated with better response to omalizumab, nasal polyposis or long-term systemic steroid use are associated with better response to antibodies targeting the IL5 pathway. Elevated total IgE concentrations and eosinophil counts are classic biological markers regularly found in severe asthma. Blood eosinophils are predictive biomarkers of response to anti-IgE, anti-IL5, anti-IL5R and anti-IL4R biotherapies. Dupilumab is particularly effective in a subgroup of patients with marked type 2 inflammation (long-term systemic corticosteroid therapy, eosinophilia≥150/μl or FENO>20 ppb). Chest imaging may help to identify severe patients by seeking out bronchial wall thickening and bronchial dilation. Study of the patient's environment is crucial insofar as exposure to tobacco, dust mites and molds, as well as outdoor and indoor air pollutants (cleaning products), can trigger asthma exacerbation. Wider and more systematic use of markers of severity or response to treatment could foster increasingly targeted and tailored approaches to severe asthma.

Optimizing asthma management: Role of long-acting muscarinic antagonists

Patients with asthma who are suboptimally responsive to inhaled corticosteroids (ICS) and long-acting β₂-agonists (LABAs) are frequently exposed to oral corticosteroids and high-dose ICS, which can lead to significant side effects. Long-acting muscarinic antagonists (LAMAs) have demonstrated efficacy and safety in a subset of these patients. This review summarizes the results of key studies using LAMAs in patients with asthma aged 12 years or older. LAMA as an add-on treatment improved lung function and asthma control in patients with uncontrolled asthma across studies. The efficacy of LAMAs as an add-on to ICS was superior to that of placebo and ICS dose escalation and comparable with that of LABAs. LAMA plus ICS plus LABA provided modest improvements in bronchodilation and increased the time to first severe exacerbation versus ICS plus LABA. Single-inhaler triple therapy was associated with decreased health care resource utilization and improved cost-effectiveness versus multiple inhalers. LAMAs were generally well tolerated; asthma exacerbations, bronchitis, and nasopharyngitis were common adverse events with LAMA in combination with ICS alone or ICS plus LABA. Thus, the overall evidence presented in this review supports the use of add-on LAMA treatment as a reasonable option in patients with asthma uncontrolled with ICS plus LABA or ICS alone.

The 5T approach in asthma: Triple Therapy Targeting Treatable Traits

Using a therapeutic strategy that is free from traditional diagnostic labels and based on the identification of "treatable traits" (TTs), which are influential in clinical presentations in each patient, might overcome the difficulties in identifying and validating asthma phenotypes and endotypes. Growing evidence is documenting the importance of using the triple therapy with ICS, LABA, and LAMAs in a single inhaler (SITT) in cases of asthma not controlled by ICS/LABA and in the prevention of exacerbations. The identification of TTs may overcome the possibility of using SITT without considering the specific needs of the patient. In effect, it allows a treatment strategy that is closer to the precision strategy now widely advocated for the management of patients with asthma. There are different TTs in asthma that may benefit from treatment with SITT, regardless of guideline recommendations. The airflow limitation and small airway dysfunction are key TTs that are present in different phenotypes/endotypes, do not depend on the degree of T2 inflammation, and respond better than other treatments to SITT. We suggest that the 5T (Triple Therapy Targeting Treatable Traits) approach should be applied to the full spectrum of asthma, not just severe asthma, and, consequently, SITT should begin earlier than currently recommended.

An update on the currently available and emerging synthetic pharmacotherapy for uncontrolled asthma

INTRODUCTION

: The treatment of uncontrolled asthma has improved because of triple therapy that includes a long-acting muscarinic antagonist (LAMA) and biological drugs, but several patients are resistant to corticosteroids and/or cannot achieve adequate asthma control using such therapies.

AREAS COVERED

: Herein, the authors review the current and emerging synthetic pharmacotherapy for uncontrolled asthma to overcome obstacles and limitations of biological therapies. The authors also provide their expert perspectives and opinion on the treatment of uncontrolled asthma.

EXPERT OPINION

: LAMAs should be added to inhaled corticosteroid/long-acting β₂-agonist combinations much earlier than currently recommended by the Global Initiative for Asthma strategy because they can influence the course of small airways disease, reducing lung hyperinflation and improving asthma control. Biological therapies are a major advance in the treatment of severe asthma, but their use is still very limited for several reasons. An alternative to overcome the use of biological therapies is to synthesise compounds that target inflammation-signalling pathways. Several pathways have been identified as potential targets to design either therapeutic or prophylactic drugs against asthma. Some new compounds have already been tested in humans, but results have often been disappointing probably because existing phenotypic and endotypic variants may unpredictably limit the therapeutic value of blocking a specific pathway in most asthmatics, although there may be a substantial benefit for a subgroup of patients.

Paucigranulocytic Asthma: Potential Pathogenetic Mechanisms, Clinical Features and Therapeutic Management

Asthma is a heterogeneous disease usually characterized by chronic airway inflammation, in which several phenotypes have been described, related to the age of onset, symptoms, inflammatory characteristics and treatment response. The identification of the inflammatory phenotype in asthma is very useful, since it allows for both the recognition of the asthmatic triggering factor as well as the optimization of treatment The paucigranulocytic phenotype of asthma (PGA) is characterized by sputum eosinophil levels <1−3% and sputum neutrophil levels < 60%. The precise characteristics and the pathobiology of PGA are not fully understood, and, in some cases, it seems to represent a previous eosinophilic phenotype with a good response to anti-inflammatory treatment. However, many patients with PGA remain uncontrolled and experience asthmatic symptoms and exacerbations, irrespective of the low grade of airway inflammation. This observation leads to the hypothesis that PGA might also be either a special phenotype driven by different kinds of cells, such as macrophages or mast cells, or a non-inflammatory phenotype with a low grade of eosinophilic inflammation. In this review, we aim to describe the special characteristics of PGA and the potential therapeutic interventions that could be offered to these patients.

The new era of add-on asthma treatments: where do we stand?

Globally, a small proportion (5-12%) of asthma patients are estimated to have severe disease. However, severe asthma accounts for disproportionately high healthcare resource utilization. The Global Initiative for Asthma (GINA) management committee recommends treating patients with asthma with inhaled corticosteroids plus long-acting β2-agonists and, when needed, adding a long-acting muscarinic receptor antagonist or biologic agent. Five biologics, targeting different effectors in the type 2 inflammatory pathway, are approved for asthma treatment. However, biologics have not been compared against each other or add-on inhaled therapies in head-to-head clinical trials. As a result, their positioning versus that of current and anticipated small-molecule strategies is largely unknown. Furthermore, with the emergence of biomarkers for predicting response to biologics, a more personalized treatment approach-currently lacking with inhaled therapies-may be possible. To gain perspective, we reviewed recent advances in asthma pathophysiology, phenotypes, and biomarkers; the place of biologics in the management and personalized treatment of severe asthma; and the future of biologics and small-molecule drugs. We propose an algorithm for the stepwise treatment of severe asthma based on recommendations in the GINA strategy document that accounts for the broad range of phenotypes targeted by inhaled therapies and the specificity of biologics. In the future, both biologics and small molecules will continue to play key roles in the individualized treatment of severe asthma. However, as targeted therapies, their application will continue to be focused on patients with certain phenotypes who meet the specific criteria for use as identified in pivotal clinical trials.

Neutrophils and Asthma

Although eosinophilic inflammation is characteristic of asthma pathogenesis, neutrophilic inflammation is also marked, and eosinophils and neutrophils can coexist in some cases. Based on the proportion of sputum cell differentiation, asthma is classified into eosinophilic asthma, neutrophilic asthma, neutrophilic and eosinophilic asthma, and paucigranulocytic asthma. Classification by bronchoalveolar lavage is also performed. Eosinophilic asthma accounts for most severe asthma cases, but neutrophilic asthma or a mixture of the two types can also present a severe phenotype. Biomarkers for the diagnosis of neutrophilic asthma include sputum neutrophils, blood neutrophils, chitinase-3-like protein, and hydrogen sulfide in sputum and serum. Thymic stromal lymphoprotein (TSLP)/T-helper 17 pathways, bacterial colonization/microbiome, neutrophil extracellular traps, and activation of nucleotide-binding oligomerization domain-like receptor family, pyrin domain-containing 3 pathways are involved in the pathophysiology of neutrophilic asthma and coexistence of obesity, gastroesophageal reflux disease, and habitual cigarette smoking have been associated with its pathogenesis. Thus, targeting neutrophilic asthma is important. Smoking cessation, neutrophil-targeting treatments, and biologics have been tested as treatments for severe asthma, but most clinical studies have not focused on neutrophilic asthma. Phosphodiesterase inhibitors, anti-TSLP antibodies, azithromycin, and anti-cholinergic agents are promising drugs for neutrophilic asthma. However, clinical research targeting neutrophilic inflammation is required to elucidate the optimal treatment.

Understanding the role of long-acting muscarinic antagonists in asthma treatment

OBJECTIVE

Long-acting muscarinic antagonists (LAMAs) have been used in the treatment of obstructive pulmonary diseases for years. Long-acting muscarinic antagonists were previously mainly used as bronchodilators in chronic obstructive pulmonary disease, but the use of LAMAs in the treatment of asthma has gained great interest. There is now ample evidence of the efficacy and safety of LAMAs as add-on therapy to inhaled corticosteroid (ICS) plus long-acting β₂-agonist (LABA) combinations in patients with moderate to severe uncontrolled asthma. Long-acting muscarinic antagonists have subsequently been included in asthma guidelines. This review summarizes the scientific evidence on the use of LAMAs in asthma and aims to provide a better understanding of the role of LAMAs in the asthma treatment care algorithm and the current gaps in our knowledge.

DATA SOURCES

PubMed review using the following words: long-acting muscarinic antagonists, asthma, muscarinic receptors, tiotropium, glycopyrronium, umeclidinium.

STUDY SELECTIONS

This review focused on the key trials that led to the inclusion of LAMAs in asthma guidelines. In addition, we highlighted a number of studies with other study designs and populations.

RESULTS

We identified 6 major studies that led to inclusion in asthma guidelines and 3 studies with other study designs and populations.

CONCLUSION

Long-acting muscarinic antagonists add-on therapy to ICS-LABA improves lung function, reduces exacerbations, and modestly improves asthma control in patients with moderate to severe asthma who are uncontrolled despite the use of ICS-LABA. Long-acting muscarinic antagonists are effective in all asthma phenotypes and endotypes.

Which Therapy for Non-Type(T)2/T2-Low Asthma

Currently, the asthmatic population is divided into Type 2-high and non-Type 2/Type 2-low asthmatics, with 50% of patients belonging to one of the two groups. Differently from T2-high, T2-low asthma has not been clearly defined yet, and the T2-low patients are identified on the basis of the absence or non-predominant expression of T2-high biomarkers. The information about the molecular mechanisms underpinning T2-low asthma is scarce, but researchers have recognized as T2-low endotypes type 1 and type 3 immune response, and remodeling events occurring without inflammatory processes. In addition, the lack of agreed biomarkers reprents a challenge for the research of an effective therapy. The first-choice medication is represented by inhaled corticosteroids despite a low efficacy is reported for/in T2-low patients. However, macrolides and long-acting anti-muscarinic drugs have been recognized as efficacious. In recent years, clinical trials targeting biomarkers playing key roles in T3 and T1 immune pathways, alarmins, and molecules involved in neutrophil recruitment have provided conflicting results probably misleading (or biased) in patients' selection. However, further studies are warranted to achieve a precise characterization of T2-low asthma with the aim of defining a tailored therapy for each single asthmatic patient.

Manifesto on inhaled triple therapy in asthma: an Interasma (Global Asthma Association - GAA) document

The optimal use of drug combinations for the management of asthma is providing significant results. This has prompted INTERASMA (Global Asthma Association) to take a position on inhaled triple therapy in asthma. Starting from an extensive literature review, Interasma executive committee discussed and approved this Manifesto, developed by Interasma scientific network (INES) members. The manifesto describes the evidence gathered to date and states, advocates, and proposes issues on Inhaled corticosteroid (ICS) plus Long-acting beta 2 agonist (LABA) and long-acting muscarinic antagonists (LAMA) with the aim of challenging assumptions, fostering commitment, and bringing about change.

2021 Brazilian Thoracic Association recommendations for the management of severe asthma

Advances in the understanding that severe asthma is a complex and heterogeneous disease and in the knowledge of the pathophysiology of asthma, with the identification of different phenotypes and endotypes, have allowed new approaches for the diagnosis and characterization of the disease and have resulted in relevant changes in pharmacological management. In this context, the definition of severe asthma has been established, being differentiated from difficult-to-control asthma. These recommendations address this topic and review advances in phenotyping, use of biomarkers, and new treatments for severe asthma. Emphasis is given to topics regarding personalized management of the patient and selection of biologicals, as well as the importance of evaluating the response to treatment. These recommendations apply to adults and children with severe asthma and are targeted at physicians involved in asthma treatment. A panel of 17 Brazilian pulmonologists was invited to review recent evidence on the diagnosis and management of severe asthma, adapting it to the Brazilian reality. Each of the experts was responsible for reviewing a topic or question relevant to the topic. In a second phase, four experts discussed and structured the texts produced, and, in the last phase, all experts reviewed and approved the present manuscript and its recommendations.

Tiotropium bromide as adjunct therapy in children with asthma: a clinical experience

Background

The Global Initiative for Asthma has only recently added tiotropium bromide as adjunct controller therapy in severe asthma (Step 4 or 5) in adults (2015) and children (2019). Although not yet approved for pediatric use by Health Canada, it has been occasionally offered by asthma specialists as a therapeutic trial in children with troublesome asthma or treatment for adverse effects. The objective of this study was to describe the indications and real-life clinical experience in initiating tiotropium in children with asthma.

Methods

We designed a retrospective mixed-method case series study of children aged 1–17 years who initiated tiotropium in our tertiary-care centre between 2013 and 2020. Clinical information was extracted from electronic medical records and tiotropium dispensing, from drug claims. Parents/children and physicians independently completed a questionnaire about treatment goals, perceived efficacy, safety, satisfaction, and lessons learned.

Results

The 34 (11 females; 23 males) children had a median (range) age of 9.1 (1.4–17.8) years. Children were primarily on Step 4 (85%) or 5 (6%) prior to tiotropium initiation, yet most (84%) did not increase their treatment step after tiotropium initiation. The physicians’ treatment goals were to improve asthma control, alleviate adverse effects of current therapy, and/or improve lung function. The most improved symptoms were coughing/moist cough, difficulty breathing, whistling breath, and bronchial secretions/mucus. Although most parents and physicians reported a significant benefit with tiotropium bromide, physicians particularly remarked, as their “lesson learned’, on the improvement in chronic symptoms in asthmatic children, particularly those with prominent moist cough and in lung function, in those with seemingly none (or incompletely) reversible obstruction as well as the ability to decrease the ICS and/or LABA dose to lessen adverse effects. A few physicians raised caution on the risk of lower adherence with an additional inhaler.

Conclusion

In children with severe asthma on Step 4 or 5, tiotropium bromide was primarily used as substitute, rather than additional, adjunct therapy to improve asthma control, alleviate adverse effects, and/or to improve lung function. The latter two indications, combined with its perceived effectiveness in children with prominent moist cough, also suggest additional indications of tiotropium to be formally explored.

Treatment approaches for the patient with T2 low asthma

OBJECTIVE

To identify treatment approaches that can be used in the management of patients with asthma who lack significant type 2 inflammation, also called T2 low asthma.

DATA SOURCES

Recent expert guideline updates on the management of asthma, recent journal articles and review articles, and foundational journal articles are referenced.

STUDY SELECTIONS

This review cites clinical cohort studies of highly characterized patients with asthma, clinical interventional trials of high impact, mechanistic studies relevant to T2 low asthma, and emerging work in this area.

RESULTS

T2 low asthma accounts for approximately one-third to one-half of individuals with asthma. Characteristics of participants with T2 low asthma include higher body mass index, cigarette smoking/smoke exposure, relative lack of responsiveness to steroids, less bronchodilator reversibility, and often the presence of neutrophilic inflammation. Multiple available interventions target these characteristics, including standard inhalers, azithromycin, and lifestyle interventions of weight loss and smoking cessation.

CONCLUSION

Treatment of T2 low asthma should involve currently available approaches and will benefit from improved definition and understanding of disease pathobiology.

Management Strategies to Reduce Exacerbations in non-T2 Asthma

There have been considerable advances in our understanding of asthmatic airway inflammation, resulting in a paradigm shift of classifying individuals on the basis of either the presence or the absence of type 2 (T2) inflammatory markers. Several novel monoclonal antibody therapies targeting T2 cytokines have demonstrated significant clinical effects including reductions in acute exacerbations and improvements in asthma-related quality of life and lung function for individuals with T2-high asthma. However, there have been fewer advancements in developing therapies for those without evidence of T2 airway inflammation (so-called non-T2 asthma). Here, we review the heterogeneity of molecular mechanisms responsible for initiation and regulation of non-T2 inflammation and discuss both current and potential future therapeutic options for individuals with non-T2 asthma.

Current long-acting muscarinic antagonists for the treatment of asthma

INTRODUCTION

The role of long-acting muscarinic antagonists (LAMAs) is well established in uncontrolled asthma, but not in milder stages.

AREAS COVERED

This review examines the main randomized controlled trials (RCTs) that have investigated LAMAs administered as monotherapy or in combination to asthmatic patients, according to the different phenotypes. It offers an overview of the role of LAMAs or their fixed dose combinations (FDCs) in the treatment across all the different stages of asthma.

EXPERT OPINION

Tiotropium is now widely recognized as treatment for moderate to severe uncontrolled asthma (step 4-5) in adults and children. The most recent new evidence is: a) in adults, three different LAMA/long-acting β₂-agonist (LABA)/inhaled corticosteroid (ICS) FDCs have been recently approved, extending the treatment options for these patients; b) therapy with LAMAs does not depend on patient's Th2 status and justifies the indication regardless of patient's phenotyping; c) in the milder stages, the high variability of response to LAMAs and the lack of a good phenotyping of patients represents the main obstacle in prescribing LAMAs. A better characterization of parasympathetic tone activity could improve LAMAs prescription.

Step-up and step-down approaches in the treatment of asthma

Introduction: Significant intraindividual and temporal variability in symptom control is a feature of asthma that requires careful monitoring and the need to periodically review and adjust therapy. Both NHLBI/NAEPP and GINA offer helpful algorithms for a stepping approach to asthma.Areas covered: The problems arisen in applying the stepwise approach to the treatment of asthma proposed by NHLBI/NAEPP and GINA algorithms and their possible alternatives.Expert opinion: The current therapeutic stepping approach to asthma, which takes into account lung function, symptoms and quality of life, is certainly useful, but it does not consider the underlying mechanisms. Furthermore, patient's overestimation or underestimation of the severity of the disease and differences in the opinions on the level of asthma control required between patients and physicians and also between physicians in both primary care and specialist settings are common and may negatively affect asthma control and future risks. A reassessment of the conventional stepping approach to management of asthma is now needed. A pragmatic approach that sets therapeutic goals for each individual and associates them with the treatable traits of asthma which, when therapeutically targeted, will in many cases help to achieve the goals, seems more reasonable than the present stepping approach.

T2-"Low" Asthma: Overview and Management Strategies

Although the term "asthma" has been applied to all patients with airway lability and variable chest symptoms for centuries, phenotypes of asthma with distinct clinical and molecular features that may warrant different treatment approaches are well recognized. Patients with type 2 (T2)-"high" asthma are characterized by upregulation of T2 immune pathways (ie, IL-4 and IL-13 gene sets) and eosinophilic airway inflammation, whereas these features are absent in patients with T2-"low" asthma and may contribute to poor responsiveness to corticosteroid treatment. This review details definitions and clinical features of T2-"low" asthma, potential mechanisms and metabolic aspects, pediatric considerations, and potential treatment approaches. Priority research questions for T2-"low" asthma are also discussed.

Asthma phenotypes and endotypes: a systematic review

INTRODUCTION

Asthma is a complex disorder characterized by expiratory airflow limitation, wheeze, shortness of breath, chest tightness and cough, which can vary over time and in intensity. Being highly heterogeneous, asthma was characterized and classified in several asthma phenotypes and endotypes from 1947 until today. The present systematic review aims to summarize and describe evidence that was published in the last ten years in the field of asthma phenotyping and endotyping.

EVIDENCE ACQUISITION

The systematic review resumed high-quality evidence (clinical trials and randomized control trials) retrieved on MEDLINE and EMBASE databanks and involving adult asthmatic populations. Analyses of literature were conducted according to PRISMA and CASP guidelines.

EVIDENCE SYNTHESIS

Querying MEDLINE and EMBASE databanks, 5019 and 12261 entries were retrieved, respectively. Applying limitations for year of publication, age of participants, and type of publication, the search results were reduced to 98 and 132 articles, respectively. After data abstraction and resolution of duplications, only 50 articles were further evaluated. The research products were then classified first in macro-areas of interest (phenotypes or endotypes) and then in detailed micro-areas.

CONCLUSIONS

This systematic review overviews the principal findings available from high-quality literature in the last decade concerning asthma phenotypes and endotypes. Asthma has been described from different points of view, characterizing symptoms, microbiota composition, comorbidities, viral infections, and airway and/or systemic inflammatory status. The comprehension of precise mechanisms underlying asthma pathogenesis is thereby the basis for the development of novel therapeutic strategies, likely essential to the development of precision medicine.

Severe Adult Asthmas: Integrating Clinical Features, Biology, and Therapeutics to Improve Outcomes

Evaluation and effective management of asthma, and in particular severe asthma, remains at the core of pulmonary practice. Over the last 20-30 years, there has been increasing appreciation that "severe asthma" encompasses multiple different subgroups or phenotypes, each with differing presentations. Using clinical phenotyping, in combination with rapidly advancing molecular tools and targeted monoclonal antibodies (human knockouts), the understanding of these phenotypes, and our ability to treat them, have greatly advanced. Type-2 (T2)-high and -low severe asthmas are now easily identified. Fractional exhaled nitric oxide and blood eosinophil counts can be routinely employed in clinical settings to identify these phenotypes and predict responses to specific therapies, meeting the initial goals of precision medicine. Integration of molecular signals, biomarkers, and clinical responses to targeted therapies has enabled identification of critical molecular pathways and, in certain phenotypes, advanced them to near-endotype status. Despite these advances, little guidance is available to determine which class of biologic is appropriate for a given patient, and current "breakthrough" therapies remain expensive and even inaccessible to many patients. Many of the most severe asthmas, with and without T2-biomarker elevations, remain poorly understood and treated. Nevertheless, conceptual understanding of "the severe asthmas" has evolved dramatically in a mere 25 years, leading to dramatic improvements in the lives of many.

Phenotype-Guided Asthma Therapy: An Alternative Approach to Guidelines

Despite recent advances in therapy, a substantial proportion of asthmatics remain not well controlled. The classical stepwise approach to pharmacological therapy in adult asthma recommends that treatment is progressively stepped up by increasing the inhaled corticosteroid (ICS) dose or by adding another controller medication- to achieve symptom control and reduce the risk of exacerbations, and stepped down after a period of control. In general, asthma guideline recommendations do not reflect that there are significant differences between ICS in terms of potency. Moreover, they do not consider efficacy and safety separately, incorrectly assuming that "low" and "high" dose categories inevitably correspond with low and high risk of systemic effects. Another point of criticism is the fact that guidelines do not take into account the inflammatory profile of the patient, although substantial groups of patients with mild and moderate asthma have little evidence of "T2-high" inflammation, and by extension are likely to show a poor response to ICS treatment. On the other hand, the latest version of the Global Initiative for Asthma (GINA) equally recommends regular ICS and ICS/formoterol as needed to prevent exacerbations in step 2 patients, without taking into consideration that the therapeutic objectives (exacerbations, symptoms) may differ between individual patients and that different goals may warrant distinct treatment strategies. In this review, we bring to the table several controversial issues concerning asthma treatment and suggest an alternative proposal that takes into consideration the potential side effects of high ICS doses, the patient's inflammatory profile and the therapeutic goals to be achieved.

Inhaled long-acting muscarinic antagonists in asthma - A narrative review

Long-acting muscarinic antagonists (LAMAs) have a recognised role in the management of chronic obstructive pulmonary disease. In asthma, muscarinic antagonists (both short- and long-acting) were historically considered less effective than β₂-agonists; only relatively recently have studies been conducted to evaluate the efficacy of LAMAs, as add-on to either inhaled corticosteroid (ICS) monotherapy or ICS/long-acting β₂-agonist (LABA) combinations. These studies led to the approval of the first LAMA, tiotropium, as an add-on therapy in patients with poorly controlled asthma. Subsequently, a number of single-inhaler ICS/LABA/LAMA triple therapies have been approved or are in clinical development for the management of asthma. There is now substantial evidence of the efficacy and safety of LAMAs in asthma that is uncontrolled despite treatment with an ICS/LABA combination. This regimen is recommended by GINA as an optimisation step for patients with severe asthma before any biologic or systemic corticosteroid treatment is initiated. This narrative review summarises the potential mechanisms of action of LAMAs in asthma, together with the initial clinical evidence supporting this use. We also discuss the studies that led to the approval of tiotropium for asthma and the data evaluating the efficacy and safety of the various triple therapies, before considering other potential uses for triple therapy.

The Impact of Muscarinic Receptor Antagonists on Airway Inflammation: A Systematic Review

Long-acting muscarinic receptor antagonists (LAMAs) are the cornerstone for the treatment of chronic obstructive pulmonary disease (COPD); furthermore, tiotropium is approved as add-on therapy in severe asthmatic patients. Accumulating evidence suggests that LAMAs may modulate airway contractility and airway hyperresponsiveness not only by blocking muscarinic acetylcholine receptors (mAchRs) expressed on airway smooth muscle but also via anti-inflammatory mechanisms by blocking mAchRs expressed on inflammatory cells, submucosal glands, and epithelial cells. The aim of this systematic review, performed according to the PRISMA-P guidelines, was to provide a synthesis of the literature on the anti-inflammatory impact of muscarinic receptor antagonists in the airways. Most of the current evidence originates from studies on tiotropium, that demonstrated a reduction in synthesis and release of cytokines and chemokines, as well as the number of total and differential inflammatory cells, induced by different pro-inflammatory stimuli. Conversely, few data are currently available for aclidinium and glycopyrronium, whereas no studies on the potential anti-inflammatory effect of umeclidinium have been reported. Overall, a large body of evidence supports the beneficial impact of tiotropium against airway inflammation. Further well-designed randomized controlled trials are needed to better elucidate the anti-inflammatory mechanisms leading to the protective effect of LAMAs against exacerbations via identifying suitable biomarkers.

Targeting eosinophils in respiratory diseases: Biological axis, emerging therapeutics and treatment modalities

Eosinophils are bi-lobed, multi-functional innate immune cells with diverse cell surface receptors that regulate local immune and inflammatory responses. Several inflammatory and infectious diseases are triggered with their build up in the blood and tissues. The mobilization of eosinophils into the lungs is regulated by a cascade of processes guided by Th2 cytokine generating T-cells. Recruitment of eosinophils essentially leads to a characteristic immune response followed by airway hyperresponsiveness and remodeling, which are hallmarks of chronic respiratory diseases. By analysing the dynamic interactions of eosinophils with their extracellular environment, which also involve signaling molecules and tissues, various therapies have been invented and developed to target respiratory diseases. Having entered clinical testing, several eosinophil targeting therapeutic agents have shown much promise and have further bridged the gap between theory and practice. Moreover, researchers now have a clearer understanding of the roles and mechanisms of eosinophils. These factors have successfully assisted molecular biologists to block specific pathways in the growth, migration and activation of eosinophils. The primary purpose of this review is to provide an overview of the eosinophil biology with a special emphasis on potential pharmacotherapeutic targets. The review also summarizes promising eosinophil-targeting agents, along with their mechanisms and rationale for use, including those in developmental pipeline, in clinical trials, or approved for other respiratory disorders.

Applying personalized medicine to adult severe asthma

Background: Severe asthma is a heterogeneous disease that consists of various phenotypes driven by different pathways. Associated with significant morbidity, an important negative impact on the quality of life of patients, and increased health care costs, severe asthma represents a challenge for the clinician. With the introduction of various antibodies that target type 2 inflammation (T2) pathways, severe asthma therapy is gradually moving to a personalized medicine approach. Objective: The purpose of this review was to emphasize the important role of personalized medicine in adult severe asthma management. Methods: An extensive research was conducted in medical literature data bases by applying terms such as "severe asthma" associated with "structured approach," "comorbidities," "biomarkers," "phenotypes/endotypes," and "biologic therapies." Results: The management of severe asthma starts with a structured approach to confirm the diagnosis, assess the adherence to medications and identify confounding factors and comorbidities. The definition of phenotypes or endotypes (phenotypes defined by mechanisms and identified through biomarkers) is an important step toward the use of personalized medicine in asthma. Severe allergic and nonallergic eosinophilic asthma are two defined T2 phenotypes for which there are efficacious targeted biologic therapies currently available. Non-T2 phenotype remains to be characterized, and less efficient target therapy exists. Conclusion: Despite important progress in applying personalized medicine to severe asthma, especially in T2 inflammatory phenotypes, future research is needed to find valid biomarkers predictive for the response to available biologic therapies to develop more effective therapies in non-T2 phenotype.

Hospitalization, Asthma Phenotypes, and Readmission Rates in Pre-school Asthma

Objective: Children with pre-school asthma suffer disproportionally more often from severe asthma exacerbations with emergency visits and hospital admissions compared to school children. Despite this high disease burden, there are only a few reports looking at this particular severe asthma cohort. Similarly, there is little real-life research on the distribution of asthma phenotypes and personalized treatment at discharge in this age group. Patients and Methods: Retrospective analysis of the electronic charts of all children aged 1-5 years with asthma hospitalizations (ICD J45) at the Frankfurt University between 2008 and 2017. An acute severe asthma exacerbation was defined as dyspnea, oxygen demand, and/or systemic steroid therapy. Age, gender, duration of hospitalization, asthma phenotype, treatment, and readmission rate were analyzed. Results: Of 572 patients, 205 met the definition of acute severe asthma. The phenotypic characterization showed 56.1% had allergic asthma, 15.2% eosinophilic asthma and 28.7% non-allergic asthma. Of these patients, 71.7% were discharged with inhaled corticosteroids (ICS) or ICS + long-acting-beta-agonists (LABA), 15.1% with leukotriene antagonists (LTRA) and 7.3% salbutamol on demand. The rate of emergency presentations (emergency department and readmission) within 12 months after discharge was high (n = 42; 20.5%). No phenotype tailored treatment was detectable. Neither the number of eosinophils (>300/μl) nor the treatment at discharge had an effect on emergency visits and readmission rate. Conclusion: Despite protective therapy with ICS, ICS + LABA, or LTRA, the readmission rate was high. Thus, current care and treatment strategies should be reevaluated continuously, in order to better control asthma in pre-school children and prevent hospitalization.

Comparing LAMA with LABA and LTRA as add-on therapies in primary care asthma management

The Global Initiative for Asthma recommends a stepwise approach to adjust asthma treatment to the needs of individual patients; inhaled corticosteroids (ICS) remain the core pharmacological treatment. However, many patients remain poorly controlled, and evidence-based algorithms to decide on the best order and rationale for add-on therapies are lacking. We explore the challenges of asthma management in primary care and review outcomes from randomised controlled trials and meta-analyses comparing the long-acting muscarinic antagonist (LAMA) tiotropium with long-acting β₂-agonists (LABAs) or leukotriene receptor antagonists (LTRAs) as add-on to ICS in patients with asthma. In adults, LAMAs and LABAs provide a greater improvement in lung function than LTRAs as add-on to ICS. In children, results were positive and comparable between therapies, but data are scarce. This information could aid decision-making in primary care, supporting the use of add-on therapy to ICS to help improve lung function, control asthma symptoms and prevent exacerbations.

Determinants of response to inhaled extrafine triple therapy in asthma: analyses of TRIMARAN and TRIGGER

Background

A number of single-inhaler triple therapies are being developed for asthma, including the extrafine formulation of beclometasone dipropionate (BDP), formoterol fumarate (FF), and glycopyrronium (G). Given asthma is a heterogenous disease, we investigated whether the clinical response to the addition of the long-acting muscarinic antagonist component within inhaled triple therapy was impacted by a range of clinical characteristics.

Methods

These were pre-specified and post-hoc sub-group analyses of TRIMARAN and TRIGGER, which were double-blind, 52-week studies comparing medium-strength (100/6/10 µg; TRIMARAN) and high-strength (200/6/10 µg; TRIGGER) BDP/FF/G with the respective BDP/FF strengths in adults with uncontrolled asthma and a history of ≥ 1 exacerbation. Co-primary endpoints were pre-dose forced expiratory volume in 1 s (FEV₁) at Week 26 and the rate of moderate-to-severe exacerbations over 52 weeks. Key secondary endpoints: peak FEV₁ at Week 26 and average morning peak expiratory flow over the first 26 weeks in each study, and severe exacerbation rate over 52 weeks (pooled data).

Results

Baseline clinical characteristics (pre-specified analyses) had no consistent effect on the lung function improvements with BDP/FF/G. For the exacerbation endpoints, sub-groups with higher reversibility gained greatest relative benefit from BDP/FF/G versus BDP/FF. In post-hoc analyses with patients sub-grouped by screening blood eosinophil values, in TRIMARAN the greatest relative effect of BDP/FF/G versus BDP/FF on the lung function endpoints was in the ≤ 300 cells/µL group; in TRIGGER, eosinophil levels did not markedly influence the relative efficacy of BDP/FF/G versus BDP/FF. Eosinophil levels did not influence relative efficacy on moderate-to-severe or severe exacerbations.

Conclusion

Overall, the relative efficacy of extrafine BDP/FF/G versus BDP/FF was not influenced by a range of clinical characteristics. However, some patient sub-groups gained additional benefit from BDP/FF/G for certain endpoints. In particular, for exacerbations the relative efficacy of BDP/FF/G was greater in more reversible patients.

Trial registration ClinicalTrials.gov: TRIMARAN, NCT02676076 (registered February 8, 2016, https://clinicaltrials.gov/ct2/show/NCT02676076?term=NCT02676076&draw=2&rank=1,); TRIGGER, NCT02676089 (registered February 8, 2016, https://clinicaltrials.gov/ct2/show/NCT02676089?term=NCT02676089&draw=2&rank=1)

Tiotropium in asthma - perspectives for the primary care physician

Asthma is a heterogeneous disease characterized by airway inflammation resulting from complex interactions between multiple hosts as well as environmental factors. As a chronic respiratory condition, asthma exerts a significant impact on patients and the healthcare system. Per the Global Initiative for Asthma (GINA), inhaled corticosteroids (ICS) with/without long-acting beta₂-agonists (LABAs) should be used as the preferred controllers for the management of asthma. Despite a range of therapeutic options, many patients with asthma remain uncontrolled, resulting in an increased risk of hospitalization and emergency room visits and a worsened quality of life. Tiotropium (Spiriva®, Boehringer Ingelheim Pharmaceuticals, Inc; 1.25 µg, two puffs, once daily), delivered via the Respimat® inhaler (Boehringer Ingelheim Pharmaceuticals, Inc.), was the first long-acting muscarinic antagonist to be approved as an add-on maintenance treatment option for patients with asthma aged ≥6 years at GINA steps 4 and 5. By binding to the muscarinic receptors M1 and M3 in the bronchial airways, tiotropium antagonizes the action of acetylcholine, leading to smooth muscle relaxation and reduced mucus secretion.The efficacy and safety of tiotropium add-on to ICS±LABA maintenance treatment have been evaluated in randomized controlled trials (RCTs) involving patients with a range of asthma severities (mild, moderate, and severe) and across age groups (children, adolescents, and adults). Add-on tiotropium was found to be well tolerated and efficacious in all RCTs. Moreover, the findings from real-world studies complement results from RCTs, showing beneficial effects of tiotropium in reducing exacerbations, hospitalization, emergency room visits, and asthma worsening.In this review article, we discuss the pathophysiology of asthma and the role of tiotropium in the management of asthma from the perspective of a primary care physician.

Efficacy and safety of once-daily single-inhaler triple therapy (FF/UMEC/VI) versus FF/VI in patients with inadequately controlled asthma (CAPTAIN): a double-blind, randomised, phase 3A trial

BACKGROUND

Despite inhaled corticosteroid plus long-acting β₂-agonist (ICS/LABA) therapy, 30-50% of patients with moderate or severe asthma remain inadequately controlled. We investigated the safety and efficacy of single-inhaler fluticasone furoate plus umeclidinium plus vilanterol (FF/UMEC/VI) compared with FF/VI.

METHODS

In this double-blind, randomised, parallel-group, phase 3A study (Clinical Study in Asthma Patients Receiving Triple Therapy in a Single Inhaler [CAPTAIN]), participants were recruited from 416 hospitals and primary care centres across 15 countries. Participants were eligible if they were aged 18 years or older, with inadequately controlled asthma (Asthma Control Questionnaire [ACQ]-6 score of ≥1·5) despite ICS/LABA, a documented health-care contact or a documented temporary change in asthma therapy for treatment of acute asthma symptoms in the year before screening, pre-bronchodilator FEV₁ between 30% and less than 85% of predicted normal value, and reversibility (defined as an increase in FEV₁ of ≥12% and ≥200 mL in the 20-60 min after four inhalations of albuterol or salbutamol) at screening. Participants were randomly assigned (1:1:1:1:1:1), via central based randomisation stratified by pre-study ICS dose at study entry, to once-daily FF/VI (100/25 μg or 200/25 μg) or FF/UMEC/VI (100/31·25/25 μg, 100/62·5/25 μg, 200/31·25/25 μg, or 200/62·5/25 μg) administered via Ellipta dry powder inhaler (Glaxo Operations UK, Hertfordshire, UK). Patients, investigators, and the funder were masked to treatment allocation. Endpoints assessed in the intention-to-treat population were change from baseline in clinic trough FEV₁ at week 24 (primary) and annualised moderate and/or severe asthma exacerbation rate (key secondary). Other secondary endpoints were change from baseline in clinic FEV₁ at 3 h post-dose, St George's Respiratory Questionnaire (SGRQ) total score, and ACQ-7 total score, all at week 24. Change from baseline in Evaluating Respiratory Symptoms in Asthma total score at weeks 21-24 was also a secondary endpoint but is not reported here. Exploratory analyses of biomarkers of type 2 airway inflammation on treatment response were also done. This study is registered with ClinicalTrials.gov, NCT02924688, and is now complete.

FINDINGS

Between Dec 16, 2016, and Aug 31, 2018, 5185 patients were screened and 2439 were recruited and randomly assigned to FF/VI (100/25 μg n=407; 200/25 μg n=406) or FF/UMEC/VI (100/31·25/25 μg n=405; 100/62·5/25 μg n=406; 200/31·25/25 μg n=404; 200/62·5/25 μg n=408), with three patients randomly assigned in error and not included in analyses. In the intention-to-treat population, 922 (38%) patients were men, the mean age was 53·2 years (SD 13·1) and body-mass index was 29·4 (6·6). Baseline demographics were generally similar across all treatment groups. The least squares mean improvement in FEV₁ change from baseline for FF/UMEC/VI 100/62·5/25 μg versus FF/VI 100/25 μg was 110 mL (95% CI 66-153; p<0·0001) and for 200/62·5/25 μg versus 200/25 μg was 92 mL (49-135; p<0·0001). Adding UMEC 31·25 μg to FF/VI produced similar improvements (FF/UMEC/VI 100/31·25/25 μg vs FF/VI 100/25 μg: 96 mL [52-139; p<0·0001]; and 200/31·25/25 μg vs 200/25 μg: 82 mL [39-125; p=0·0002]). These results were supported by the analysis of clinic FEV₁ at 3 h post-dose. Non-significant reductions in moderate and/or severe exacerbation rates were observed for FF/UMEC 62·5 μg/VI versus FF/VI (pooled analysis), with rates lower in FF 200 μg-containing versus FF 100 μg-containing treatment groups. All pooled treatment groups demonstrated mean improvements (decreases) in SGRQ total score at week 24 compared with baseline in excess of the minimal clinically important difference of 4 points; however, there were no differences between treatment groups. For mean change from baseline to week 24 in asthma control questionnaire-7 score, improvements (decreases) exceeding the minimal clinically important difference of 0·5 points were observed in all pooled treatment groups. Adding UMEC to FF/VI resulted in small, dose-related improvements compared with FF/VI (pooled analysis: FF/UMEC 31·25 μg/VI versus FF/VI, -0·06 (95% CI -0·12 to 0·01; p=0·094) FF/UMEC 62·5 μg/VI versus FF/VI, -0·09 (-0·16 to -0·02, p=0·0084). By contrast with adding UMEC, the effects of higher dose FF on clinic trough FEV₁ and annualised moderate and/or severe exacerbation rate were increased in patients with higher baseline blood eosinophil count and exhaled nitric oxide. Occurrence of adverse events was similar across treatment groups (patients with at least one event ranged from 210 [52%] to 258 [63%]), with the most commonly reported adverse events being nasopharyngitis (51 [13%]-63 [15%]), headache (19 [5%]-36 [9%]), and upper respiratory tract infection (13 [3%]-24 [6%]). The incidence of serious adverse events was similar across all groups (range 18 [4%]-25 [6%)). Three deaths occurred, of which one was considered to be related to study drug (pulmonary embolism in a patient in the FF/UMEC/VI 100/31·25/25 μg group).

INTERPRETATION

In patients with uncontrolled moderate or severe asthma on ICS/LABA, adding UMEC improved lung function but did not lead to a significant reduction in moderate and/or severe exacerbations. For such patients, single-inhaler FF/UMEC/VI is an effective treatment option with a favourable risk-benefit profile. Higher dose FF primarily reduced the rate of exacerbations, particularly in patients with raised biomarkers of type 2 airway inflammation. Further confirmatory studies into the differentiating effect of type 2 inflammatory biomarkers on treatment outcomes in asthma are required to build on these exploratory findings and further guide clinical practice.

FUNDING

GSK.

A Proposed Approach to Chronic Airway Disease (CAD) Using Therapeutic Goals and Treatable Traits: A Look to the Future

Chronic airflow obstruction affects a wide range of airway diseases, the most frequent of which are asthma, COPD, and bronchiectasis; they are clearly identifiable in their extremes, but quite frequently overlap in some of their pathophysiological and clinical characteristics. This has generated the description of new mixed or overlapping disease phenotypes with no clear biological grounds. In this special article, a group of experts provides their perspective and proposes approaching the treatment of chronic airway disease (CAD) through the identification of a series of therapeutic goals (TG) linked to treatable traits (TT) - understood as clinical, physiological, or biological characteristics that are quantifiable using biomarkers. This therapeutic approach needs validating in a clinical trial with the strategy of identification of TG and treatment according to TT for each patient independently of their prior diagnosis.

Multidimensional Assessment of Asthma Identifies Clinically Relevant Phenotype Overlap: A Cross-Sectional Study

BACKGROUND

Asthma is a heterogeneous disease with multiple phenotypes; however, the relevance of phenotype overlap remains largely unexplored.

OBJECTIVE

To examine the relationship between phenotype overlap and clinical and inflammatory profiles of asthma.

METHODS

In this cross-sectional study, adult participants with stable asthma (n = 522) underwent multidimensional assessments. The 10 most common phenotypes of asthma were defined and then classified into those commonly associated with Type (T) 2 or non-T2 inflammation. Furthermore, phenotype overlap scores (POS), representing the cumulative concomitant phenotypes, were used to analyze its association with clinical and inflammatory asthmatic profiles.

RESULTS

Among the 522 participants, 73.4% (n = 383) had phenotype overlap, and mixed T2 and non-T2 inflammation coexisted in 47.5% (n = 248). T2 POS was positively associated with eosinophils, IgE, and fractional exhaled nitric oxide (FeNO), and negatively with Asthma Quality of Life Questionnaire (AQLQ), sputum neutrophils, IL-17A, IL-8, and TNF-α. Non-T2 POS was positively associated with Asthma Control Questionnaire, neutrophils and sputum IL-8, and negatively with AQLQ, forced expiratory volume in 1 s, blood eosinophils, IgE, and FeNO (all P < .05). Patients with phenotypes that are associated with mixed T2 and non-T2 inflammation had elevated T2 inflammation biomarkers but worse asthma control. Both T2 (adjusted β = -0.191, P = .035) and non-T2 (adjusted β = 0.310, P < .001) POS were significantly associated with severe exacerbations.

CONCLUSIONS

Phenotype overlap is extremely common in asthmatic patients and significantly associated with clinical and inflammatory profiles. Patients with phenotypes associated with mixed T2 and non-T2 inflammation might be unresponsive to medications owing to increased non-T2 inflammation. Multidimensional asthma assessment identifies clinically relevant phenotype overlap.

Emerging muscarinic receptor antagonists for the treatment of asthma

INTRODUCTION

The increased acetylcholine signaling in asthma pathophysiology offers the rationale for the use of LAMAs in the treatment of asthmatic patients. Tiotropium is still the only LAMA approved for use in asthma but there is a real interest in developing novel LAMAs for the treatment of asthma, or at least to extend this indication to other LAMAs already on the market.

AREAS COVERED

We examined and discussed trials and research that have studied or are evaluating the role of LAMAs already on the market in asthma and possible novel muscarinic acetylcholine receptor antagonists.

EXPERT OPINION

Glycopyrronium and umeclidinium will soon be included in the GINA strategy with the same current indications of tiotropium. It is likely that the choice of the LAMA will be influenced not so much by its pharmacological profile as by the type of triple therapy chosen. It is extremely difficult to identify a new LAMA that is more effective than tiotropium, but is it plausible that new technologies that will allow delivering the drug in a more targeted way and with a lower risk of adverse effects may represent the real progress in the use of LAMAs in asthma in the coming years.

New perspectives on the role of muscarinic antagonists in asthma therapy

INTRODUCTION

There is increasing evidence that tiotropium, a long-acting muscarinic agent (LAMA), is useful in the presence of severe-uncontrolled asthma despite the optimization of therapy with inhaled corticosteroids (ICSs) and long-acting β₂ agonists (LABAs) as recommended by the current guidelines. Furthermore, in recent years there have been several  preclinical and clinical studies on the pharmacological and therapeutic impact of other LAMAs in asthma.

AREAS COVERED

We have conducted an extensive search on muscarinic antagonists in asthma therapy throughout several sources and discuss what has emerged in the last 3 years (January 2017-March 2020).

EXPERT OPINION

New evidence indicates that the effectiveness of adding a LAMA, at least tiotropium, is independent of the degree of the type 2 inflammation and age of patient. Therefore, tiotropium can be administered without the need for patient phenotyping. Umeclidinium and glycopyrronium also appear effective in asthma. Initial treatment with LAMA+ICS for those with mild asthma may be an equally effective therapeutic option as LABA+ICS but this hypothesis should be confirmed by statistically powered trials.