"Refractory" eosinophilic airway inflammation in severe asthma: effect of parenteral corticosteroids

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Mechanisms underlying corticosteroid resistance in patients with asthma: a review of current knowledge

INTRODUCTION

Corticosteroids are the most cost-effective anti-inflammatory drugs available for the treatment of asthma. Despite their effectiveness, several asthmatic patients have corticosteroid resistance or insensitivity and exhibit a poor response. Corticosteroid insensitivity implies a poor prognosis due to challenges in finding alternative therapeutic options for asthma.

AREAS COVERED

In this review, we describe asthma phenotypes and endotypes, as well as their differential responsiveness to corticosteroids. In addition, we describe the mechanism of action of corticosteroids underlying their regulation of the expression of glucocorticoid receptors (GRs) and their anti-inflammatory effects. Furthermore, we summarize the mechanistic evidence underlying corticosteroid-insensitive asthma, which is mainly related to changes in GR gene expression, structure, and post-transcriptional modifications. Finally, various pharmacological strategies designed to reverse corticosteroid insensitivity are discussed.

EXPERT OPINION

Corticosteroid insensitivity is influenced by the asthma phenotype, endotype, and severity, and serves as an indication for biological therapy. The molecular mechanisms underlying corticosteroid-insensitive asthma have been used to develop targeted therapeutic strategies. However, the lack of clinical trials prevents the clinical application of these treatments.

Airway remodeling heterogeneity in asthma and its relationship to disease outcomes

Asthma affects an estimated 262 million people worldwide and caused over 461,000 deaths in 2019. The disease is characterized by chronic airway inflammation, reversible bronchoconstriction, and airway remodeling. Longitudinal studies have shown that current treatments for asthma (inhaled bronchodilators and corticosteroids) can reduce the frequency of exacerbations, but do not modify disease outcomes over time. Further, longitudinal studies in children to adulthood have shown that these treatments do not improve asthma severity or fixed airflow obstruction over time. In asthma, fixed airflow obstruction is caused by remodeling of the airway wall, but such airway remodeling also significantly contributes to airway closure during bronchoconstriction in acute asthmatic episodes. The goal of the current review is to understand what is known about the heterogeneity of airway remodeling in asthma and how this contributes to the disease process. We provide an overview of the existing knowledge on airway remodeling features observed in asthma, including loss of epithelial integrity, mucous cell metaplasia, extracellular matrix remodeling in both the airways and vessels, angiogenesis, and increased smooth muscle mass. While such studies have provided extensive knowledge on different aspects of airway remodeling, they have relied on biopsy sampling or pathological assessment of lungs from fatal asthma patients, which have limitations for understanding airway heterogeneity and the entire asthma syndrome. To further understand the heterogeneity of airway remodeling in asthma, we highlight the potential of in vivo imaging tools such as computed tomography and magnetic resonance imaging. Such volumetric imaging tools provide the opportunity to assess the heterogeneity of airway remodeling within the whole lung and have led to the novel identification of heterogenous gas trapping and mucus plugging as important predictors of patient outcomes. Lastly, we summarize the current knowledge of modification of airway remodeling with available asthma therapeutics to highlight the need for future studies that use in vivo imaging tools to assess airway remodeling outcomes.

Corticosteroid Responsiveness Following Mepolizumab in Severe Eosinophilic Asthma-A Randomized, Placebo-Controlled Crossover Trial (MAPLE)

BACKGROUND

Mepolizumab inhibits IL-5 activity and reduces exacerbation frequency and maintenance oral corticosteroid (OCS) dosage in patients with severe eosinophilic asthma (SEA). Some patients remain dependent on OCS despite anti-IL-5 treatment, suggesting residual corticosteroid-responsive mechanisms.

OBJECTIVE

To determine the clinical and anti-inflammatory effects of OCS in patients with SEA on mepolizumab.

METHODS

We conducted a randomized, triple-blind, placebo-controlled crossover trial of prednisolone (0.5 mg/kg/d, maximum 40 mg/d, for 14 ± 2 days) in adults with SEA after 12 or more weeks of mepolizumab. We compared change in asthma symptoms, quality of life, lung function measured by spirometry and airwave oscillometry, fractional exhaled nitric oxide, and blood and sputum eosinophil cell count after prednisolone and placebo treatment.

RESULTS

A total of 27 patients completed the study. Prednisolone did not improve 5-item Asthma Control Questionnaire (mean difference in change for prednisolone vs placebo, -0.23; 95% CI, -0.58 to 0.11), mini-Asthma Quality of Life Questionnaire (0.03; 95% CI, -0.26 to 0.42), St. George's Respiratory Questionnaire (0.24; 95% CI, -3.20 to 3.69), or Visual Analogue Scale scores for overall asthma symptoms (0.11; 95% CI, -0.58 to 0.80). The mean difference for FEV₁ in favor of prednisolone was 105 mL (95% CI, -4 to 213 mL); forced expiratory flow at 25% and 75% 484 mL/s (95% CI, 151 to 816 mL/s); fractional exhaled nitric oxide reduction 41% (95% CI, 25% to 54%); blood eosinophil count reduction 49% (95% CI, 31% to 62%); and percentage of sputum eosinophil reduction 71% (95% CI, 26% to 89%).

CONCLUSIONS

OCS improved small-airway obstruction and reduced biomarkers of type 2 inflammation but had no significant effect on symptoms or quality of life in patients with SEA receiving treatment with mepolizumab.

Longitudinal Impact of Sputum Inflammatory Phenotypes on Small Airway Dysfunction and Disease Outcomes in Asthma

BACKGROUND

Little is known about the relationship between airway inflammatory phenotypes and some important asthma features such as small airway dysfunction (SAD).

OBJECTIVE

To describe the longitudinal impact of airway inflammatory phenotypes on SAD and asthma outcomes.

METHODS

We measured eosinophil and neutrophil counts in induced sputum at baseline and 1 year later to stratify 197 adult patients with asthma into 4 inflammatory phenotypes. We conducted a comprehensive assessment of lung function using spirometry, body plethysmography, impulse oscillometry, and inert gas single and multiple breath washouts. We compared lung function, asthma severity, exacerbation frequency, and symptom control between the phenotypes. We studied the longitudinal impact of persistent sputum inflammatory phenotypes and the change of sputum cell counts on lung function.

RESULTS

Patients were stratified into eosinophilic (23%, n = 45), neutrophilic (33%, n = 62), mixed granulocytic (22%, n = 43), and paucigranulocytic (24%, n = 47) phenotypes. Patients with eosinophilic and mixed granulocytic asthma had higher rates of airflow obstruction and severe exacerbation as well as poorer symptom control than patients with paucigranulocytic asthma. All SAD measures were worse in patients with eosinophilic and mixed asthma than in those with paucigranulocytic asthma (all P values <.05). Eosinophilic asthma also indicated worse distal airflow obstruction, increased ventilation inhomogeneity (all P values <.05), and higher tendency for severe exacerbation (P = .07) than neutrophilic asthma. Longitudinally, persistent mixed granulocytic asthma was associated with the worst follow-up measures of SAD compared with persistent neutrophilic, persistent paucigranulocytic, or nonpersistent asthma phenotypes. In patients with stable forced expiratory volume in 1 second (FEV1), the mean increase in small airway resistance (R5-20) was greater in patients with persistent mixed granulocytic asthma (+103%) than in patients with persistent neutrophilic (+26%), P = .040, or persistent paucigranulocytic asthma (-41%), P = .028. Multivariate models adjusted for confounders and treatment with inhaled or oral corticosteroids or antieosinophilic biologics indicated that the change of sputum eosinophil rather than neutrophil counts is an independent predictor for the longitudinal change in FEV1, forced expiratory flow at 25% to 75% of forced vital capacity, specific effective airway resistance, residual lung volume, and lung clearance index.

CONCLUSIONS

In asthma, airway eosinophilic inflammation is the main driver of lung function impairment and poor disease outcomes, which might also be aggravated by the coexistence of airway neutrophilia to confer a severe mixed granulocytic asthma phenotype. Persistent airway eosinophilia might be associated with dynamic SAD even in patients with stable FEV1.

Corticosteroid resistance in asthma: Cellular and molecular mechanisms

Inhaled glucocorticoids (GCs) are drugs widely used as treatment for asthma patients. They prevent the recruitment and activation of lung immune and inflammatory cells and, moreover, have profound effects on airway structural cells to reverse the effects of disease on airway inflammation. GCs bind to a specific receptor, the glucocorticoid receptor (GR), which is a member of the nuclear receptor superfamily and modulates pro- and anti-inflammatory gene transcription through a number of distinct and complementary mechanisms. Targets genes include many pro-inflammatory mediators such as chemokines, cytokines, growth factors and their receptors. Inhaled GCs are very effective for most asthma patients with little, if any, systemic side effects depending upon the dose. However, some patients show poor asthma control even after the administration of high doses of topical or even systemic GCs. Several mechanisms relating to inflammation have been considered to be responsible for the onset of the relative GC resistance observed in these patients. In these patients, the side-effect profile of GCs prevent continued use of high doses and new drugs are needed. Targeting the defective pathways associated with GC function in these patients may also reactivate GC responsiveness.

Chronic Allergen Challenge Induces Corticosteroid Insensitivity With Persistent Airway Remodeling and Type 2 Inflammation

Type 2-high severe asthma is described as a distinct endotype with Th2 inflammation, high eosinophil lung infiltration, impaired lung function, and reduced corticosteroid sensitivity. While the inflammatory milieu is similar to mild asthma, patients with type 2-high severe asthma likely have underlying mechanisms that sustain asthma pathophysiology despite corticosteroid treatments. Acute and chronic allergen models induce robust type 2 inflammatory responses, however differences in corticosteroid sensitivity remains poorly understood. In the present study, we sensitized and challenged mice with ovalbumin (OVA; acute model) or mixed allergens (MA; chronic model). Corticosteroid sensitivity was assessed by administering vehicle, 1, or 3 mg/kg fluticasone propionate (FP) and examining key asthmatic features such as airway inflammation, remodeling, hyperresponsiveness, and antioxidant capacity. Both acute and chronic allergen exposure exhibited enhanced AHR, immune cell infiltration, airway inflammation, and remodeling, but corticosteroids were unable to fully alleviate inflammation, AHR, and airway smooth muscle mass in MA-challenged mice. While there were no differences in antioxidant capacity, persistent IL-4+ Th2 cell population suggests the MA model induces type 2 inflammation that is insensitive to corticosteroids. Our data indicate that chronic allergen exposure is associated with more persistent type 2 immune responses and corticosteroid insensitivity. Understanding differences between acute and chronic allergen models could unlock underlying mechanisms related to type 2-high severe asthma.

Anti-Interleukin-5 Therapy Is Associated with Attenuated Lung Function Decline in Severe Eosinophilic Asthma Patients from the Belgian Severe Asthma Registry

BACKGROUND

Asthmatics have accelerated lung function decline over time compared with healthy individuals.

OBJECTIVE

To evaluate risk factors for accelerated lung function decline.

METHODS

In a longitudinal analysis on severe asthmatics enrolled in the Belgian Severe Asthma Registry with at least 2 visits a minimum of 12 months apart, we compared characteristics of patients with and without decline (loss of post-bronchodilation forced expiratory volume in 1 s [FEV₁] (% predicted)/y greater than zero) over time. Multiple linear regression was applied to study the factors independently associated with FEV₁ decline.

RESULTS

In the overall population (n = 318), median annual FEV₁ decline was 0.27 (-4.22 to 3.80) % predicted/y over a period of 23 months (12-41 months). Asthma was less controlled at baseline in nondecliners than in decliners (53%). Lung function and residual volume at baseline were higher in the declining group. Decliners presented with increased bronchial reactivity (ie, a lower provocative concentration of methacholine causing a 20% fall in FEV₁) at baseline. Twenty-five percent of nondecliners were started on anti-interleukin-5 (anti-IL-5) for severe eosinophilic asthma during the study compared with 10% of decliners. The multivariable model suggested that Asthma Control Questionnaire score at baseline, late-onset asthma, and addition of anti-IL-5 during follow-up were associated with lower FEV₁ decline, independently from other variables such as evolution in exacerbations, smoking status, inhaled corticosteroids or oral corticosteroids dose, or add-on anti-immunoglobulin E over time, whereas reversibility to salbutamol and higher FEV₁ were associated with accelerated FEV₁ decline.

CONCLUSIONS

Add-on therapy with anti-IL-5 in severe eosinophilic asthma was associated with an attenuated FEV₁ decline. The causality of this observation should, however, be confirmed in future prospective controlled studies.

Targeting dynamic hyperinflation in moderate-to-severe asthma: a randomised controlled trial

Background

Dynamic hyperinflation is highly prevalent in moderate-to-severe asthma, which may significantly impede activities of daily life. We hypothesised that dynamic hyperinflation in asthma is due to inflammation of large and small airways and can be reduced by systemic anti-inflammatory treatment. Therefore, we investigated the effect of systemic glucocorticoids on dynamic hyperinflation in moderate-to-severe asthma patients and explored the relationships between inflammatory markers and changes in dynamic hyperinflation.

Methods

In this randomised placebo-controlled trial we included 32 asthma patients on inhaled glucocorticoid therapy showing dynamic hyperinflation, defined by a ≥10% reduction in inspiratory capacity measured by standardised metronome-paced tachypnea test. Patients received either triamcinolone (80 mg) or placebo intramuscularly. Before and 2 weeks after treatment, patients completed respiratory health questionnaires, had blood eosinophils and exhaled nitric oxide levels measured, and underwent lung function and dynamic hyperinflation testing.

Results

After adjustment for potential confounders, dynamic hyperinflation was significantly reduced by 28.1% in the triamcinolone group and increased by 9.4% in the placebo group (p=0.027). In the triamcinolone-treated patients, the reduction in dynamic hyperinflation was greater in patients with higher blood eosinophils at baseline (r=−0.592, p=0.020) and tended to be associated with a reduction in blood eosinophils (r=0.412, p=0.127) and exhaled nitric oxide (r=0.442, p=0.099).

Conclusions

This exploratory study suggests that dynamic hyperinflation in asthma can be reduced by systemic anti-inflammatory treatment, particularly in patients with elevated blood eosinophils. This supports the hypothesis that dynamic hyperinflation in asthma is due to airway inflammation and should be considered an important target for treatment.

Dynamic hyperinflation: a target for treatment in asthma, which can be reduced by systemic anti-inflammatory treatmenthttps://bit.ly/3gfyxYv

Responsiveness to Parenteral Corticosteroids and Lung Function Trajectory in Adults with Moderate-to-Severe Asthma

Rationale: It is unclear why select patients with moderate-to-severe asthma continue to lose lung function despite therapy. We hypothesized that participants with the smallest responses to parenteral corticosteroids have the greatest risk of undergoing a severe decline in lung function.Objectives: To evaluate corticosteroid-response phenotypes as longitudinal predictors of lung decline.Methods: Adults within the NHLBI SARP III (Severe Asthma Research Program III) who had undergone a course of intramuscular triamcinolone at baseline and at ≥2 annual follow-up visits were evaluated. Longitudinal slopes were calculated for each participant's post-bronchodilator FEV₁% predicted. Categories of participant FEV₁ slope were defined: severe decline, >2% loss/yr; mild decline, >0.5-2.0% loss/yr; no change, 0.5% loss/yr to <1% gain/yr; and improvement, ≥1% gain/yr. Regression models were used to develop predictors of severe decline.Measurements and Main Results: Of 396 participants, 78 had severe decline, 91 had mild decline, 114 had no change, and 113 showed improvement. The triamcinolone-induced difference in the post-bronchodilator FEV₁% predicted (derived by baseline subtraction) was related to the 4-year change in lung function or slope category in univariable models (P < 0.001). For each 5% decrement in the triamcinolone-induced difference the FEV1% predicted, there was a 50% increase in the odds of being in the severe decline group (odds ratio, 1.5; 95% confidence interval, 1.3-1.8), when adjusted for baseline FEV₁, exacerbation history, blood eosinophils and body mass index.Conclusions: Failure to improve the post-bronchodilator FEV₁ after a challenge with parenteral corticosteroids is an evoked biomarker for patients at risk for a severe decline in lung function.

Efficacy and safety of mepolizumab in Korean patients with severe eosinophilic asthma from the DREAM and MENSA studies

BACKGROUND/AIMS

The efficacy and safety of mepolizumab in patients with severe eosinophilic asthma has been evaluated in a global clinical trial programme. This post hoc analysis assesses the efficacy and safety of mepolizumab in Korean patients.

METHODS

Data from Korean patients in the Phase III, placebo-controlled, randomised DREAM (MEA112997/NCT01000506) and MENSA (MEA115588/ NCT01691521) studies were included. Patients ≥ 12 years old with severe eosinophilic asthma received mepolizumab (DREAM: 75, 250 or 750 mg intravenously [IV]; MENSA: 75 mg IV or 100 mg subcutaneously [SC]), or placebo every 4 weeks for 52 weeks (DREAM) or 32 weeks (MENSA). The primary outcome was the rate of clinically significant asthma exacerbations. Secondary outcomes included forced expiratory volume in 1 second (FEV1), Asthma Control Questionnaire (ACQ) and St George's Respiratory Questionnaire (SGRQ) scores (MENSA only). Blood eosinophil counts (BEC) and safety were assessed throughout.

RESULTS

Reductions in the rate of clinically significant asthma exacerbations were observed with the approved (100 mg SC) and bioequivalent (75 mg IV) doses of mepolizumab in Korean patients who participated in DREAM and MENSA. In MENSA, trends for improvements from baseline at week 32 in pre-bronchodilator FEV1 (75 mg IV group), ACQ-5 and SGRQ scores (in both treatment groups) were seen versus placebo in Korean patients. Incidence of on-treatment adverse events was similar in Korean patients versus non-Korean patients as were observed reductions from baseline in BEC.

CONCLUSION

Mepolizumab treatment provided clinical benefits for Korean patients with severe eosinophilic asthma; the safety profile is consistent with the overall population.

Modern View of Neutrophilic Asthma Molecular Mechanisms and Therapy

For a long time asthma was commonly considered as a homogeneous disease. However, recent studies provide increasing evidence of its heterogeneity and existence of different phenotypes of the disease. Currently, classification of asthma into several phenotypes is based on clinical and physiological features, anamnesis, and response to therapy. This review describes five most frequently identified asthma phenotypes. Neutrophilic asthma (NA) deserves special attention, since neutrophilic inflammation of the lungs is closely associated with severity of the disease and with the resistance to conventional corticosteroid therapy. This review focuses on molecular mechanisms of neutrophilic asthma pathogenesis and on the role of Th1- and Th17-cells in the development of this type of asthma. In addition, this review presents current knowledge of neutrophil biology. It has been established that human neutrophils are represented by at least three subpopulations with different biological functions. Therefore, total elimination of neutrophils from the lungs can result in negative consequences. Based on the new knowledge of NA pathogenesis and biology of neutrophils, the review summarizes current approaches for treatment of neutrophilic asthma and suggests new promising ways to treat this type of asthma that could be developed in future.

Biochanin A Ameliorates Ovalbumin-induced Airway Inflammation through Peroxisome Proliferator-Activated Receptor-Gamma in a Mouse Model

OBJECTIVE

Asthma is an inflammatory airway disease affecting most of the population in the world. The current medication for asthma relieves airway inflammation but it has serious adverse effects. Biochanin A (BCA), a phytoestrogen, is an active component present in red clover, alfalfa, soy having anti-oxidant and anti-inflammatory properties. BCA was identified as a natural activator of peroxisome proliferator-activated receptor-gamma (PPARγ).

METHODS

The study aims to evaluate the effects of BCA in ovalbumin (OVA)-induced murine model of asthma and to study the role of PPARγ.

RESULTS

We found that BCA administration reduced the severity of murine allergic asthma as evidenced histologically, and measurement of allergen-specific IgE levels in serum as well as in BAL fluid. BCA also reversed the elevated levels of inflammatory cytokines, cell infiltration, protein leakage into the airways and expression of hemoxygenase-1 in OVA-induced lungs. Further, we confirmed that BCA mediated inhibitory effects are mediated through PPARγ as assessed by treatment with PPARγ antagonist GW9662.

CONCLUSION

Our results suggest that BCA is efficacious in a preclinical model of asthma and may have the potential for the treatment of asthma in humans.

Risk Factors Predicting Severe Asthma Exacerbations in Adult Asthmatics: A Real-World Clinical Evidence

PURPOSE

Minimizing the future risk of asthma exacerbation (AE) is one of the main goals of asthma management. We investigated prognostic factors for risk of severe AE (SAE) in a real-world clinical setting.

METHODS

This is an observational study evaluating subjects who were diagnosed with asthma and treated with anti-asthmatic medications from January 1995 to June 2018. Risk factors for SAE were analyzed in 2 treatment periods (during the initial 2 years and the following 3-10 years of treatment) using the big data of electronic medical records.

RESULTS

In this study, 5,058 adult asthmatics were enrolled; 1,335 (28.64%) experienced ≥ 1 SAE during the initial 2 years of treatment. Female sex, higher peripheral eosinophil/basophil counts, and lower levels of forced expiratory volume in 1 second (FEV1; %) were factors predicting the risk of SAEs (P < 0.001 for all). Higher serum total immunoglobulin E levels increased the risk of SAEs among the patients having ≤ 2 SAEs (P = 0.025). Patients with more frequent SAEs during the initial 2 years of treatment had significantly higher risks of SAEs during the following years of treatment (P < 0.001, for all) (patients with ≥ 4 SAEs, odds ratio [OR], 29.147; those with 3 SAEs, OR, 14.819; those with 2 SAEs, OR, 9.867; those with 1 SAE, OR, 5.116), had higher maintenance doses of systemic steroids, and showed more gradual decline in FEV1 (%) and FEV1/forced vital capacity levels maintained during the following years of treatment (P < 0.001 for all).

CONCLUSIONS

Asthmatics having risk factors for SAEs (female sex, higher peripheral eosinophil/basophil counts, and lower FEV1) should be strictly monitored to prevent future risk and improve clinical outcomes.

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.

Serum potential biomarkers according to sputum inflammatory cell profiles in adult asthmatics

BACKGROUND/AIMS

Asthma is not a single disease but, rather, a heterogeneous inf lammatory disorder with various pathogenic mechanisms. We analyzed the associations between the cellular profile of sputum and the serum levels of inflammatory mediators/cytokines in a cohort of adult asthmatics.

METHODS

We recruited 421 adult asthmatic patients. All subjects were classified into four groups according to their sputum cellular profiles: G1, eosinophilic; G2, mixed granulocytic; G3, neutrophilic; and G4, paucigranulocytic. Serum levels of cytokines and mediators including periostin, eosinophil-derived neurotoxin (EDN), S100A9, and folliculin were quantified.

RESULTS

Among 421 patients, G1 accounted for 149 (35.4%), G2 for 71 (16.9%), G3 for 155 (36.8%), and G4 for 46 (10.9%). Serum periostin and EDN levels were significantly higher in G1 (p = 0.004, and p = 0.031) than in the others. Serum S100A9 levels were elevated in G2 and G3 (p = 0.008). Serum folliculin levels differed significantly among the four groups, with the highest level in G4 (p = 0.042). To identify G1 from G1 plus G2 groups, the optimal serum cut-off levels were 1.71 ng/mL for periostin, and 1.61 ng/mL for EDN. When these two parameters were combined, the sensitivity was 76.0% and the specificity was 64.3% (area under the curve, 0.701; p = 0.004).

CONCLUSION

The serum periostin and EDN levels may be used as predictors to discriminate the eosinophilic asthma group from patients having eosinophilic or mixed granulocytic asthma, and the serum folliculin level is significantly elevated in patients with paucigranulocytic asthma compared to those with different inflammatory cell profile.

Systematic Assessment of Difficult-to-Treat Asthma: Principles and Perspectives

Difficult-to-treat asthma affects a minority of adults and children with asthma but represents a challenging mix of misdiagnosis, multimorbidity, inadequate self-management, severe airway pathobiology, and treatment complications. Management of these patients extends beyond asthma pharmacotherapy, because multiple other patient-related domains need to be addressed as well. Such complexity can hinder adequate clinical assessment even when performed in specialist practice. Systematic assessment undertaken by specialized multidisciplinary teams brings a broad range of resources to bear on patients with difficult-to-treat asthma. Although the concept of systematic assessment is not new, practices vary considerably and implementation is not universal. Nevertheless, assessment protocols are already in place in several institutions worldwide, and outcomes after such assessments have been highly encouraging. This review discusses the rationale, components, and benefits of systematic assessment, outlining its clinical utility and the available evidence for improved outcomes. It describes a range of service configurations and assessment approaches, drawing examples from severe asthma centers around the world to highlight common essential elements. It also provides a framework for establishing such services and discusses practical considerations for implementation.

Short-term pulmonary infiltrate with eosinophilia caused by asthma: a phenotype of severe, eosinophilic asthma? Five cases and a review of the literature

Background

Asthma is often accompanied by peripheral eosinophilia and eosinophilic airway inflammation. This article explores the relationship between asthma and short-term pulmonary infiltrate with eosinophilia, which results from irregular asthma treatment.

Case presentation

We report five unique cases of asthma-induced short-term eosinophilic pneumonia encountered at our pulmonary and critical care centre in Hunan, China, from January 1, 2014, to August 31, 2018. The 5 asthma patients were women with persistent dyspnoea symptoms, an increased peripheral eosinophil count and a high level of exhaled nitric oxide (FeNO). Chest CT revealed multiple infiltrates and ground-glass opacities in both lung fields in all 5 patients. Four of the 5 patients had increased eosinophils in bronchoalveolar lavage (BAL). Three were positive for reversibility in lung function testing, and two had eosinophil infiltration as revealed by lung biopsy. No antibiotic treatment was given, and after a short period of glucocorticoid therapy and inhaled corticosteroid plus long-acting β2-agonist (ICS + LABA) treatment, the symptoms of all of the patients disappeared. In addition, their blood eosinophils returned to normal, and their lung lesions were quickly absorbed and improved.

Conclusion

These cases show a unique association between short-term eosinophilic pneumonia and asthma. The occurrence of eosinophilic pneumonia can prove fatal during a serious asthma attack. Additionally, the presence of peripheral eosinophilia with lung infiltrates poses a diagnostic challenge for clinicians by creating suspicion of pulmonary infiltrate with eosinophilia when present in asthmatic patients.

Targeting cytokines to treat asthma and chronic obstructive pulmonary disease

Cytokines play a key role in orchestrating and perpetuating the chronic airway inflammation in asthma and chronic obstructive pulmonary disease (COPD), making them attractive targets for treating these disorders. Asthma and some cases of COPD are mainly driven by type 2 immune responses, which comprise increased airway eosinophils, T helper 2 (T_H2) cells and group 2 innate lymphoid cells (ILC2s) and the secretion of IL-4, IL-5 and IL-13. Clinical trials of antibodies that block these interleukins have shown reduced acute exacerbations and oral corticosteroid use and improvements in lung function and symptoms in selected patients. More recent approaches that block upstream cytokines, such as thymic stromal lymphopoietin (TSLP), show promise in improving patient outcome. Importantly, the clinical trials in cytokine blockade have highlighted the crucial importance of patient selection for the successful use of these expensive therapies and the need for biomarkers to better predict drug responses.

The prevalence and disease burden of severe eosinophilic asthma in Japan

Background: There are limited data on the prevalence and burden of severe eosinophilic asthma (SEA) both in Japan and globally. This study aimed to assess the prevalence and burden of SEA in Japan. Methods: This study was a retrospective, observational cohort analysis using health records or health insurance claims from patients with severe asthma treated at Kyoto University Hospital. The primary outcome was the prevalence of SEA, defined as a baseline blood eosinophil count ≥300 cells/μL. Secondary outcomes included frequency and risk factors of asthma exacerbations, and asthma-related healthcare resource utilization and costs. Results: Overall, 217 patients with severe asthma were included; 160 (74%) had eosinophil assessments. Of these, 97cases (61%), 54cases (34%), and 33cases (21%) had a blood eosinophil count ≥150, ≥300, and ≥500 cells/μL, respectively. Proportion of SEA was 34%. Blood eosinophil count was not associated with a significantly increased frequency of exacerbations. In the eosinophilic group, lower % forced expiratory volume in 1 second and higher fractional exhaled nitric oxide were predictive risk factors, while the existence of exacerbation history was a predictive risk factor for asthma exacerbations in the non-eosinophilic group. Severe asthma management cost was estimated as ¥357,958/patient-year, and asthma exacerbations as ¥26,124/patient-year. Conclusions: Approximately, one-third of patients with severe asthma in Japan have SEA. While risk factors for exacerbations differed between SEA and severe non-eosinophilic asthma, both subgroups were associated with substantial disease and economic burden. From subgroup analysis, blood eosinophil counts could be an important consideration in severe asthma management.

Repeated exacerbation of asthma: An intrinsic phenotype of uncontrolled asthma

Asthma is a chronic disease of the airways affecting a large number of people across the globe. Uncontrolled asthma poses an emotional as well as the physical burden on patients and results in a great economic burden. “Exacerbation-prone phenotype” asthmatics are a cluster of patients who may suffer from more frequent and severe exacerbations than other asthmatics. Factors such as inadequate symptom control, improper adherence to medications, and incorrect use of inhalers are responsible for frequent asthma exacerbations. Caring for the patient with “exacerbation-prone asthma” needs participation from both the doctor as well as the patient. Self-management, improving knowledge about the disease, control of comorbidities, and a stepwise approach with the use of a single inhaler maintenance and reliever therapy in patients with severe asthma could help in delivering better care for the “exacerbation-prone phenotype” of asthmatics.

Treating Pediatric Asthma According Guidelines

Asthma is a common chronic inflammatory disorder of the lower respiratory airways in childhood. The management of asthma exacerbations and the disease control are major concerns for clinical practice. The Global Strategy for Asthma Management and Prevention, published by GINA, updated in 2017, the British Thoracic Society/Scottish Intercollegiate Guideline Network, revised in 2016, the National Institute for Health and Care Excellence asthma guideline consultation, available in 2017, are widely accepted documents, frequently implemented, with conflicting advices, and different conclusion on asthma definition and treatment. An International Consensus on Pediatric Asthma was carried out in 2012 by a Committee with expertise in the field, to critically review differences on current guidelines. In addition, the specific issue of treating severe and difficult asthma has been recently highlighted throughout the International European Respiratory Society/American Thoracic Society guidelines on severe asthma. The aim of this paper is to describe conventional treatments and some new therapeutic approaches to pediatric asthma according to guidelines, highlighting key aspects, and differences on proposed clinical recommendations for asthma management. Age specific therapy are proposed in steps, according to clinical severity and the level of disease control. If control is not achieved within 3 months, stepping-up should be considered; otherwise, if control is achieved after 3 months, stepping down may be considered. The most used drug classes of asthma medications are beta-2 adrenergic agonists, corticosteroids, and leukotriene modifiers. Intramuscolar triamcinolone has been used for severe asthma treatment. Chromones and xanthines have been extensively used in the past, but they have shown limits related to their efficacy and safety profile. Omalizumab, a monoclonal antibody against IgE, is an immunomodulatory biological agent, used as new drug in patients with confirmed IgE-mediated allergic asthma, only for patient's specific range of total IgE level. There are low evidences in the efficacy of metotrexate, as well as macrolide antibiotics in children with asthma. Antifungal agents are also not recommended in asthmatic patients. Non-pharmacological measures that may improve patient's quality of life should also be attempted. We conclude that treatment decisions on childhood asthma management should be critically made, pondering the differences suggested by agreed international consensus documents.

Use of biomarkers to identify phenotypes and endotypes of severeasthma

OBJECTIVE

Severe asthma can be classified into phenotypes and endotypes, which may inform clinicians about inflammatory pathways leading to disease and ultimately guide optimal therapeutic strategy. Biomarkers, objectively measurable characteristics of the disease, are of increasing interest to clinicians and researchers as powerful tools to distinguish among the severe asthma phenotypes and endotypes. The objective of this review is to highlight current knowledge of biomarker applications to identify phenotypes and endotypes of severe asthma.

DATA SOURCES

Sources used include observational cohorts, clinical trials, translational studies, comprehensive reviews, and expert/taskforce statements.

STUDY SELECTIONS

Included studies were selected for their relevance to the topic and for strength of data or study design.

RESULTS

In severe asthma, biomarkers can be used for diagnosis of phenotype or endotype, can also be predictive of clinical outcomes or response to therapy, and may be dynamic with time or therapy. Fully determining phenotype or endotype of severe asthma will require interpretation of combinations of commercially available biomarkers.

CONCLUSION

Biomarkers have multiple potential clinical applications in severe asthma. Novel biomarkers may add accuracy to this field.

Pruning of the Pulmonary Vasculature in Asthma. The Severe Asthma Research Program (SARP) Cohort

RATIONALE

Loss of the peripheral pulmonary vasculature, termed vascular pruning, is associated with disease severity in patients with chronic obstructive pulmonary disease.

OBJECTIVES

To determine if pulmonary vascular pruning is associated with asthma severity and exacerbations.

METHODS

We measured the total pulmonary blood vessel volume (TBV) and the blood vessel volume of vessels less than 5 mm2 in cross-sectional area (BV5) and of vessels less than 10 mm2 (BV10) in cross-sectional area on noncontrast computed tomographic scans of participants from the Severe Asthma Research Program. Lower values of the BV5 to TBV ratio (BV5/TBV) and the BV10 to TBV ratio (BV10/TBV) represented vascular pruning (loss of the peripheral pulmonary vasculature).

MEASUREMENTS AND MAIN RESULTS

Compared with healthy control subjects, patients with severe asthma had more pulmonary vascular pruning. Among those with asthma, those with poor asthma control had more pruning than those with well-controlled disease. Pruning of the pulmonary vasculature was also associated with lower percent predicted FEV1 and FVC, greater peripheral and sputum eosinophilia, and higher BAL serum amyloid A/lipoxin A4 ratio but not with low-attenuation area or with sputum neutrophilia. Compared with individuals with less pruning, individuals with the most vascular pruning had 150% greater odds of reporting an asthma exacerbation (odds ratio, 2.50; confidence interval, 1.05-5.98; P = 0.039 for BV10/TBV) and reported 45% more asthma exacerbations during follow-up (incidence rate ratio, 1.45; confidence interval, 1.02-2.06; P = 0.036 for BV10/TBV).

CONCLUSIONS

Pruning of the peripheral pulmonary vasculature is associated with asthma severity, control, and exacerbations, and with lung function and eosinophilia.

Moving toward consensus on diagnosis and management of severe asthma in adults

Asthma is a considerable health problem with an increasing global prevalence. The burden of severe asthma is expected to notably increase in the following years. Some misleading concepts that sometimes appear in the literature can drive the physician responsible for a patient's management to make incorrect decisions. Furthermore, some of the concepts that appear in the literature and in the guidelines may not be clear to understand, follow or adapt to regional and local realities. This could again drive the physicians responsible for a patient's management to make incorrect clinical judgments. In this article, we review the definition, prevalence and immunopathology of severe asthma, describe the asthma phenotypes, clinical features and comorbidities, the diagnosis of severe asthma and personalized asthma treatment. At the end, we offer a treatment approach based on literature publications, personalized medicine and marketed biologic treatment options.

Airway pathology in severe asthma is related to airflow obstruction but not symptom control

BACKGROUND

Patients with asthma present structural and inflammatory alterations that are believed to play a role in disease severity. However, airway remodeling and inflammation have not been extensively investigated in relation to both symptom control and airflow obstruction in severe asthmatics. We aimed to investigate several inflammatory and structural pathological features in bronchial biopsies of severe asthmatics that could be related to symptom control and airflow obstruction after standardized treatment.

METHODS

Fifty severe asthmatics received prednisone 40 mg/d for 2 weeks and maintenance therapy with budesonide/formoterol 400/12 μg twice daily + budesonide/formoterol 200/6 μg as needed for 12 weeks. Endobronchial biopsies were performed at the end of 12 weeks. We performed extensive immunopathological analyses of airway tissue inflammation and remodeling features in patients stratified by asthma symptom control and by airflow obstruction.

RESULTS

Airway tissue inflammation and remodeling were not associated with symptom control. Asthmatics with persistent airflow obstruction had greater airway smooth muscle (Asm) area with decreased periostin and transforming growth factor beta-positive cells within Asm bundles, in addition to lower numbers of chymase-positive mast cells in the submucosa compared to patients with nonpersistent obstruction.

CONCLUSIONS

Symptom control in severe asthmatics was not associated with airway tissue inflammation and remodeling, although persistent airflow obstruction in these patients was associated with bronchial inflammation and airway structural changes.

Asthma

Asthma-one of the most common chronic, non-communicable diseases in children and adults-is characterised by variable respiratory symptoms and variable airflow limitation. Asthma is a consequence of complex gene-environment interactions, with heterogeneity in clinical presentation and the type and intensity of airway inflammation and remodelling. The goal of asthma treatment is to achieve good asthma control-ie, to minimise symptom burden and risk of exacerbations. Anti-inflammatory and bronchodilator treatments are the mainstay of asthma therapy and are used in a stepwise approach. Pharmacological treatment is based on a cycle of assessment and re-evaluation of symptom control, risk factors, comorbidities, side-effects, and patient satisfaction by means of shared decisions. Asthma is classed as severe when requiring high-intensity treatment to keep it under control, or if it remains uncontrolled despite treatment. New biological therapies for treatment of severe asthma, together with developments in biomarkers, present opportunities for phenotype-specific interventions and realisation of more personalised treatment. In this Seminar, we provide a clinically focused overview of asthma, including epidemiology, pathophysiology, clinical diagnosis, asthma phenotypes, severe asthma, acute exacerbations, and clinical management of disease in adults and children older than 5 years. Emerging therapies, controversies, and uncertainties in asthma management are also discussed.

Asthma management: A new phenotype-based approach using presence of eosinophilia and allergy

Asthma is a heterogeneous disease. The Czech Pneumology and Allergology Societies commissioned 10 experts to review the literature and create joint national guidelines for managing asthma, reflecting this heterogeneity. The aim was to develop an easy-to-use diagnostic strategy as a rational approach to the widening opportunities for the use of phenotype-targeted therapy. The guidelines were presented on websites for public comments by members of both the societies. The reviewers' comments contributed to creating the final version of the guidelines. The key hallmark of the diagnostic approach is the pragmatic concept, which assesses the presence of allergy and eosinophilia in each asthmatic patient. The guidelines define three clinically relevant asthma phenotypes: eosinophilic allergic asthma, eosinophilic nonallergic asthma and noneosinophilic nonallergic asthma. The resulting multifunctional classification describing the severity, level of control and phenotype is the starting point for a comprehensive treatment strategy. The level of control is constantly confronted with the intensity of the common stepwise pharmacotherapy, and the concurrently included phenotyping is essential for phenotype-specific therapy. The concept of the asthma approach with assessing the presence of eosinophilia and allergy provides a way for more precise diagnosis, which is a prerequisite for using widening options of personalized therapy.

Baseline Features of the Severe Asthma Research Program (SARP III) Cohort: Differences with Age

BACKGROUND

The effect of age on asthma severity is poorly understood.

OBJECTIVES

The objective of this study was to compare the baseline features of severe and nonsevere asthma in the Severe Asthma Research Program (SARP) III cohort, and examine in cross section the effects of age on those features.

METHODS

SARP III is a National Institutes of Health/National Heart Lung Blood Institute multisite 3-year cohort study conducted to investigate mechanisms of severe asthma. The sample included 188 children (111 severe, 77 nonsevere) and 526 adults (313 severe, 213 nonsevere) characterized for demographic features, symptoms, health care utilization, lung function, and inflammatory markers compared by age and severity.

RESULTS

Compared with children with nonsevere asthma, children with severe asthma had more symptoms and more historical exacerbations, but no difference in body weight, post-bronchodilator lung function, or inflammatory markers. After childhood, and increasing with age, the cohort had a higher proportion of women, less allergen sensitization, and overall fewer blood eosinophils. Enrollment of participants with severe asthma was highest in middle-aged adults, who were older, more obese, with greater airflow limitation and higher blood eosinophils, but less allergen sensitization than adults with nonsevere asthma.

CONCLUSIONS

The phenotypic features of asthma differ by severity and with advancing age. With advancing age, patients with severe asthma are more obese, have greater airflow limitation, less allergen sensitization, and variable type 2 inflammation. Novel mechanisms besides type 2 inflammatory pathways may inform the severe asthma phenotype with advancing age.

A new combination therapy for asthma using dual-function dexamethasone-conjugated polyethylenimine and vitamin D binding protein siRNA

Asthma is a multifactorial disease that is influenced by the interaction of genetic and environmental factors. Because of its complex nature, there is no cure for asthma currently. Instead, reliever and controller medications are used to treat asthma. Unfortunately, conventional treatments do not work in some severe cases of asthma. In addition, there may be adverse, systemic effects of long-term treatment with high-dose inhaled corticosteroids (ICSs) as a controller medication. Therefore, we attempted to develop a novel combination therapy for asthma. Our regimen included dexamethasone as a controller medication and vitamin D binding protein (VDBP) small interfering RNA (siRNA) as a novel target therapeutic. The dexamethasone moiety of DEXA-PEI (dexamethasone-conjugated polyethylenimine) was used as an ICS, combined with anti-VDBP treatment via delivery of VDBP siRNA, using DEXA-PEI as a siRNA carrier molecule. Treatment with DEXA-PEI/VDBP siRNA effectively reduced the ovalbumin sensitization/challenge-induced enhancement of airway inflammation, goblet cell hyperplasia and expression of interleukin (IL)-4, IL-13 and CCL11. These findings suggest that the DEXA-PEI/VDBP siRNA can be developed as a potent asthma therapeutic by dose-reducing ICSs and using a multitarget therapeutic method.

Efficacy and safety of mepolizumab in Japanese patients with severe eosinophilic asthma

BACKGROUND

The MENSA trial assessed the efficacy and safety of mepolizumab in patients with severe eosinophilic asthma. This report describes the efficacy and safety of mepolizumab in Japanese patients from MENSA.

METHODS

A post hoc analysis of the Japanese subgroup from the randomized, double-blind, placebo-controlled, double-dummy, Phase III MENSA trial (NCT01691521). Patients ≥12 years with severe eosinophilic asthma received mepolizumab 75 mg intravenously (IV), 100 mg subcutaneously (SC), or placebo, every 4 weeks for 32 weeks. The primary endpoint was the annualized rate of exacerbations. Secondary and other endpoints included annualized rate of exacerbations requiring emergency department (ED) visit/hospitalization, morning peak expiratory flow (PEF), St George's Respiratory Questionnaire (SGRQ) score and eosinophil counts. Adverse events (AEs) were monitored.

RESULTS

In the Japanese subgroup (N = 50), the rate of clinically significant exacerbations was reduced by 90% (rate ratio [RR]: 0.10; 95% confidence interval [CI]: 0.02-0.57; P = 0.010) with mepolizumab IV and 62% (RR: 0.38; 95% CI: 0.12-1.18; P = 0.094) with mepolizumab SC, versus placebo. No exacerbations requiring ED visit/hospitalization were reported with mepolizumab IV; exacerbations were reduced by 73% (RR: 0.27; 95% CI: 0.06-1.29; P = 0.102) with mepolizumab SC versus placebo. Compared with placebo, mepolizumab IV and SC numerically increased morning PEF from baseline by 40 L/min and 13 L/min, improved quality of life by greater than the minimal clinically important difference (SGRQ: 9.5 [P = 0.083] and 7.9 [P = 0.171] points) and reduced eosinophil counts. AE incidence was similar between treatments. Results were broadly consistent with the overall population.

CONCLUSIONS

Mepolizumab was efficacious and well tolerated in Japanese patients with severe eosinophilic asthma, producing similar responses to the overall MENSA population.

A sputum gene expression signature predicts oral corticosteroid response in asthma

Biomarkers that predict responses to oral corticosteroids (OCS) facilitate patient selection for asthma treatment. We hypothesised that asthma patients would respond differently to OCS therapy, with biomarkers and inflammometry predicting response.Adults with stable asthma underwent a randomised controlled cross-over trial of 50 mg prednisolone daily for 10 days (n=55). A six-gene expression biomarker signature (CLC, CPA3, DNASE1L3, IL1B, ALPL and CXCR2) in induced sputum, and eosinophils in blood and sputum were assessed and predictors of response were investigated (changes in forced expiratory volume in 1 s (ΔFEV₁), six-item Asthma Control Questionnaire score (ΔACQ6) or exhaled nitric oxide fraction (ΔF_eNO)).At baseline, responders to OCS (n=25) had upregulated mast cell CPA3 gene expression, poorer lung function, and higher sputum and blood eosinophils. Following treatment, CLC and CPA3 gene expression was reduced, whereas DNASE1L3, IL1B, ALPL and CXCR2 expression remained unchanged. Receiver operating characteristic (ROC) analysis showed the six-gene expression biomarker signature as a better predictor of clinically significant responses to OCS than blood and sputum eosinophils.The six-gene expression signature including eosinophil and Th2 related mast cell biomarkers showed greater precision in predicting OCS response in stable asthma. Thus, a novel sputum gene expression signature highlights an additional role of mast cells in asthma, and could be a useful measurement to guide OCS therapy in asthma.

Route of Administration Affects Corticosteroid Sensitivity of a Combined Ovalbumin and Lipopolysaccharide Model of Asthma Exacerbation in Guinea Pigs

Lipopolysaccharide (LPS) contributes to asthma exacerbations and development of inhaled corticosteroid insensitivity. Complete resistance to systemic corticosteroids is rare, and most patients lie on a continuum of steroid responsiveness. This study aimed to examine the sensitivity of combined ovalbumin- (Ova) and LPS-induced functional and inflammatory responses to inhaled and systemic corticosteroid in conscious guinea pigs to test the hypothesis that the route of administration affects sensitivity. Guinea pigs were sensitized to Ova and challenged with inhaled Ova alone or combined with LPS. Airway function was determined by measuring specific airway conductance via whole-body plethysmography. Airway hyper-responsiveness to histamine was determined before and 24 hours post-Ova challenge. Airway inflammation and underlying mechanisms were determined from bronchoalveolar lavage cell counts and lung tissue cytokines. Vehicle or dexamethasone was administered by once-daily i.p. injection (5, 10, or 20 mg/kg) or twice-daily inhalation (4 or 20 mg/ml) for 6 days before Ova challenge or Ova with LPS. LPS exacerbated Ova-induced responses, elongating early asthmatic responses (EAR), prolonging histamine bronchoconstriction, and further elevating airway inflammation. Intraperitoneal dexamethasone (20 mg/kg) significantly reduced the elongated EAR and airway inflammation but not the increased bronchoconstriction to histamine. In contrast, inhaled dexamethasone (20 mg/ml), which inhibited responses to Ova alone, did not significantly reduce functional and inflammatory responses to combined Ova and LPS. Combined Ova and LPS–induced functional and inflammatory responses are insensitive to inhaled, but they are only partially sensitive to systemic, dexamethasone. This finding suggests that the route of corticosteroid administration may be important in determining corticosteroid sensitivity of asthmatic responses.

Effects of Age and Disease Severity on Systemic Corticosteroid Responses in Asthma

RATIONALE

Phenotypic distinctions between severe asthma (SA) and nonsevere asthma (NONSA) may be confounded by differential adherence or incorrect use of corticosteroids.

OBJECTIVES

To determine if there are persistent phenotypic distinctions between SA (as defined by 2014 American Thoracic Society/European Respiratory Society guidelines) and NONSA after intramuscular triamcinolone acetonide (TA), and to identify predictors of a corticosteroid response in these populations.

METHODS

A total of 526 adults age 18 years and older (315 SA) and 188 children age 6 to less than 18 years (107 SA) in the NHLBI Severe Asthma Research Program III were characterized before and 3 weeks after TA. The primary outcome for corticosteroid response was defined as greater than or equal to 10-point improvement in percent predicted FEV1.

MEASUREMENTS AND MAIN RESULTS

Adult asthma groups exhibited a small but significant mean FEV1% predicted improvement after TA (SA group mean difference, 3.4%; 95% confidence interval, 2.2-4.7%; P = 0.001), whereas children did not. Adult SA continued to manifest lower FEV1 and worse asthma control as compared with NONSA after TA. In children, after TA only prebronchodilator FEV1 distinguished SA from NONSA. A total of 21% of adults with SA and 20% of children with SA achieved greater than or equal to 10% improvement after TA. Baseline bronchodilator response and fractional exhaled nitric oxide had good sensitivity and specificity for predicting response in all groups except children with NONSA.

CONCLUSIONS

One in five patients with SA exhibit greater than or equal to 10% improvement in FEV1 with parenteral corticosteroid. Those likely to respond had greater bronchodilator responsiveness and fractional exhaled nitric oxide levels. In adults, differences in airflow obstruction and symptoms between SA and NONSA persist after parenteral corticosteroids, suggesting a component of corticosteroid nonresponsive pathobiology in adults with SA that may differ in children. Clinical trial registered with www.clinicaltrials.gov (NCT 01606826).

Clinical phenotypes in asthma during childhood

Asthma is a heterogeneous disease characterized by numerous phenotypes relating to age of onset, triggers, comorbidities, severity (assessed by multiple exacerbations, lung function pattern) and finally the inflammatory cells involved in the pathophysiologic pathway. These phenotypes can vary over time in relation to changes in the principal triggers involved in the aetiology of the disease. Nevertheless, in a patient with multiple allergies and early-onset disease (defined as multiple sensitizations and allergic comorbidities), the prognosis of asthma is poor with a high risk of persistence and severity of the disease during childhood. Future research will focus on classifying phenotypes into groups based on pathophysiologic mechanisms (endotypes) and the biomarkers attached to these endotypes, which could predict prognosis and lead to targeted therapy. Currently, these biomarkers are related to inflammatory cells associated with the asthma endotype, essentially eosinophils and neutrophils (and related cytokines) attached to Th-2 and non Th-1 pathways, respectively. The most severe asthma (refractory asthma) is linked to neutrophil-derived inflammation (frequently associated with female sex, obesity and possibly disorganized airway microbiota) encountered in very young children or teenagers. Severe asthma is also linked to or a marked eosinophil inflammatory process (frequently associated with multiple atopy and, more rarely, with non-atopic hypereosinophilic asthma in children) and frequently encountered in teenagers. Severe phenotypes of asthma could also play a role in the origin of chronic obstructive pulmonary disease in adult life.

The transition of sputum inflammatory cell profiles is variable in stable asthma patients

Background

The sputum inflammatory cell profile is an important indicator for classifying asthma phenotypes.

Objective

To investigate if sputum inflammatory cell profile remains stable and there are different characteristics between groups that show different profile over time in stable asthmatic patients.

Methods

A total of 149 asthmatic patients, who were clinically stable at the time of sputum examination and had undergone sputum analysis twice, were subjected to a detailed review. Eosinophilic inflammation was diagnosed when the proportion of the sputum eosinophils was >3%. We divided the patients into 4 groups according to the transition patterns of their sputum profiles: group 1, persistent eosinophilia; group 2, eosinophilic to noneosinophilic; group 3, noneosinophilic to eosinophilic; and group 4, persistent noneosinophilia. The results of the pulmonary function tests and other clinical parameters were compared between these 4 groups.

Results

Thirty-four of the initially eosinophilic asthmatic patients (39.5%; 34 of 86 patients) demonstrated noneosinophilic airway inflammation at their second sputum examination, and 24 of the initially noneosinophilic patients (38.1%; 24 of 63 patients) demonstrated eosinophilic airway inflammation at follow-up. Various clinical parameters, except the blood eosinophil count, demonstrated no significant differences between the eosinophilic and noneosinophilic asthmatic patients or among the 4 groups.

Conclusion

A substantial proportion of asthmatic patients who demonstrate a certain sputum inflammatory cell profile at the initial examination demonstrated profile transition in clinically stable settings over time. The clinical significance of using induced sputum analysis to phenotype stable asthmatic patients requires further evaluation.

Can severe asthmatic patients achieve asthma control? A systematic approach in patients with difficult to control asthma followed in a specialized clinic

Background

Despite advances in asthma treatment, severe asthma (SA) still results in high morbidity and use of health resources. Our hypothesis was that SA patients would achieve adequate control with a systematic protocol, including oral corticosteroids, budesonide/formoterol maintenance and reliever therapy and a multidisciplinary approach to improve adherence.

Methods

Non-controlled (NC) SA patients were enrolled to receive 2 weeks of oral corticosteroids and 12 weeks of formoterol + budesonide. Assessments included asthma control questionnaire (ACQ), asthma control test (ACT), daily symptom diary, lung function and health-related quality of life (HRQoL) questionnaires.

Results

Of 51 patients, 13 (25.5%) achieved control. NC patients had higher utilization of health resources and higher exacerbation rates. Both controlled (C) and NC patients had significantly reduced ACQ scores after oral corticosteroid treatment. After 12 weeks, C patients continued improving. NC patients did not have significant changes. A similar pattern was found regarding lung function, use of rescue medication, and days free of symptoms. After 2 weeks of oral corticosteroids, an increase occurred in those who achieved the ACQ cut off; however, 53.8% of C patients had an ACQ < 1.57 versus 21.1% of NC patients (p = 0.03). Both groups had low HRQoL at baseline with improvement after intervention.

Conclusions

Despite rigorous, optimized follow-up treatment, 75% of SA patients did not achieve adequate symptom control and presented with impaired quality of life. Conversely, application of a low-cost, easy to implement systematic protocol can prevent up to 25% of SA patients from up-titrating to new and complex therapies, thus reducing costs and morbidity.

Trial registration

Retrospectively registered at ClinicalTrial.gov on 22 February 2010 (NCT01089322).

Asthma transition from childhood into adulthood

Asthma is the most prevalent chronic respiratory disease both in children and adults and resembles a complex syndrome rather than a single disease. Different methods have been developed to better characterise distinct asthma phenotypes in childhood and adulthood. In studies of adults, most phenotyping relies on biomaterials from the lower airways; however, this information is missing in paediatric studies because of restricted accessibility. Few patients show symptoms throughout childhood, adolescence, and adulthood. Risk factors for this might be genetics, family history of asthma and atopy, infections early in life, allergic diseases, and lung function deficits. In turn, a large proportion of children with asthma lose their symptoms during school age and adolescence. This improved prognosis, which might also reflect a better treatment response, is associated with being male and with milder and less allergic disease. Importantly, whether clinical remission of symptoms equals the disappearance of underlying pathology is unknown. In fact, airway hyper-responsiveness and airway inflammation might remain despite the absence of overt symptoms. Additionally, a new-onset of asthma symptoms is apparent in adulthood, especially in women and in the case of impaired lung function. However, many patients do not remember childhood symptoms, which might reflect relapse rather than true initiation. Both relapse and adult-onset of asthma symptoms have been associated with allergic disease and sensitisation in addition to airway hyper-responsiveness. Thus, asthma symptoms beginning in adults might have originated in childhood. Equivocally, persistence into, relapse, and new-onset of symptoms in adulthood have all been related to active smoking. However, underlying mechanisms for the associations remain unclear, and future asthma research should therefore integrate standardised molecular approaches in identical ways in both paediatric and adult populations and in longitudinal studies.

Systemic Corticosteroid Responses in Children with Severe Asthma: Phenotypic and Endotypic Features

BACKGROUND

Severe asthma in children is a heterogeneous disorder associated with variable responses to corticosteroid treatment. Criterion standards for corticosteroid responsiveness assessment in children are lacking.

OBJECTIVE

This study sought to characterize systemic corticosteroid responses in children with severe asthma after treatment with intramuscular triamcinolone and to identify phenotypic and molecular predictors of an intramuscular triamcinolone response.

METHODS

Asthma-related quality of life, exhaled nitric oxide, blood eosinophils, lung function, and inflammatory cytokine and chemokine mRNA gene expression in peripheral blood mononuclear cells were assessed in 56 children with severe asthma at baseline and 14 days after intramuscular triamcinolone injection. The Asthma Control Questionnaire was used to classify children with severe asthma into corticosteroid response groups.

RESULTS

Three groups of children with severe asthma were identified: controlled severe asthma, children who achieved control after triamcinolone, and children who did not achieve control. At baseline, these groups were phenotypically similar. After triamcinolone, discordance between symptoms, lung function, exhaled nitric oxide, and blood eosinophils was noted. Clinical phenotypic predictors were of limited utility in predicting the triamcinolone response, whereas systemic mRNA expression of inflammatory cytokines and chemokines related to IL-2, IL-10, and TNF signaling pathways, namely, AIMP1, CCR2, IL10RB, and IL5, strongly differentiated children who failed to achieve control with triamcinolone administration.

CONCLUSIONS

Systemic corticosteroid responsiveness in children with severe asthma is heterogeneous. Alternative prediction models that include molecular endotypic as well as clinical phenotypic features are needed to identify which children derive the most clinical benefit from systemic corticosteroid step-up therapy given the potential side effects.

Refractory asthma - An old disorder: Novel approaches for effective control

Bronchial asthma is an inflammatory disorder of airways characterized by hyper-responsiveness to a wide range of triggers and is associated with variable airflow obstruction that remits spontaneously or with the treatment. Several phenotype of asthma not responding to the currently acceptable standard therapy of high dose inhaled gluco-corticosteroids along with along acting β2 agonists come under the purview of refractory asthma. This condition is a heterogeneous and complex disease that requires a multi-disciplinary approach to identify accurately various sub-phenotypes to enable improved understanding of the pathogenesis and development of effective management strategies including use of novel methods and targeted therapy.

Mepolizumab for the reduction of exacerbations in severe eosinophilic asthma

Asthma affects over 300 million people worldwide and is severe in 10% of sufferers. Severe asthma is associated with greater morbidity and mortality particularly as a consequence of frequent exacerbations. Advances in approaches to phenotype the heterogeneity of severe asthma has established the importance of eosinophilic inflammation and emerging new therapies are broadly designed to target T2-mediated eosinophilic inflammation with the aim to reduce exacerbation frequency. Here, we summarize the evidence that eosinophilic asthma is an important pheno(endo)type and identifies a group at risk of exacerbations; that established therapies reduce exacerbations, particularly in eosinophilic severe asthma; and discuss the role of mepolizumab, an IL-5 neutralising monoclonal antibody therapy, in reducing exacerbations in severe eosinophilic asthma compared to established and other emerging therapies.

Assessment of corticosteroid response in pediatric patients with severe asthma by using a multidomain approach

BACKGROUND

There is no agreed upon definition of systemic corticosteroid response in asthmatic children. Moreover, pediatric severe therapy-resistant asthma (STRA) is heterogeneous, and thus response to steroids is unlikely to be uniform in all patients.

OBJECTIVE

We sought to evaluate the utility of a multidomain approach incorporating symptoms, lung function, and inflammation to determine steroid responsiveness in pediatric patients with STRA.

METHODS

Eighty-two children (median age, 12 years) with STRA received a clinically indicated dose of intramuscular steroid. Changes in 4 separate domains were assessed 4 weeks after intramuscular triamcinolone acetonide: normalization of (1) symptoms (Asthma Control Test score, >19/25 or 50% increase), (2) spirometric results (FEV1 ≥80% of predicted value or ≥15% increase), (3) fraction of exhaled nitric oxide levels (<24 ppb), and (4) sputum eosinophil counts (<2.5%). Fifty-four of 82 children had complete data in all 4 domains.

RESULTS

Twenty-three (43%) of 54 children had a symptom response, 29 (54%) of 54 had a lung function response, 28 (52%) of 54 had a fraction of exhaled nitric oxide response, and 29 (54%) of 54 had a sputum eosinophil response. Although a similar proportion of children responded to systemic corticosteroids in each domain, there were no reliable predictors of a response pattern. Seven (13%) of 54 were complete responders (response in all domains), 8 (15%) of 54 were nonresponders (no response in any domain), and 39 (72%) of 54 were partial responders (response in ≥1 domain).

CONCLUSIONS

A multidomain evaluation of systemic steroid responsiveness using pragmatic clinical assessments confirms childhood STRA is heterogeneous and that a complete response in symptoms and inflammatory and physiologic parameters is rare. Individual response patterns to systemic steroids might be useful in guiding the choice of add-on therapies in each child as a step toward achieving personalized medicine.

Asthma phenotyping: a necessity for improved therapeutic precision and new targeted therapies

Asthma is a common heterogeneous disease with a complex pathophysiology that carries a significant mortality rate and high morbidity. Current therapies based on inhaled corticosteroids and long-acting β-agonists remain effective in a large proportion of patients with asthma, but ~10% (considered to have 'severe asthma') do not respond to these treatments even at high doses or with the use of oral corticosteroids. Analytical clustering methods have revealed phenotypes that include dependence on high-dose corticosteroid treatment, severe airflow obstruction and recurrent exacerbations associated with an allergic background and late onset of disease. One severe phenotype is eosinophilic inflammation-predominant asthma, with late-onset disease, rhinosinusitis, aspirin sensitivity and exacerbations. Blood and sputum eosinophilia have been used to distinguish patients with high Th2 inflammation and to predict therapeutic response to treatments targeted towards Th2-associated cytokines. New therapies in the form of humanized antibodies against Th2 targets, such as anti-IgE, anti-IL4Rα, anti-IL-5 and anti-IL-13 antibodies, have shown encouraging results in terms of reduction in exacerbations and improvement in airflow in patients with a 'Th2-high' expression profile and blood eosinophilia. Research efforts are now focusing on elucidating the phenotypes underlying the non-Th2-high (or Th2-low) group, which constitutes ~50% of severe asthma cases. There is an increasing need to use biomarkers to indicate the group of patients who will respond to a specifically targeted treatment. The use of improved tools to measure activity of disease, a better definition of severe asthma and the delineation of inflammatory pathways with omics analyses using computational tools, will lead to better-defined phenotypes for specific therapies.

Molecular phenotyping and biomarker development: are we on our way towards targeted therapy for severe asthma?

Although different phenotypes of severe asthma can be identified, all are characterized by common symptoms. Due to their heterogeneity, they exhibit differences in pathogenesis, etiology and clinical responses to therapeutic approaches. The identification of distinct molecular phenotypes to define severe asthmatic patients will allow us to better understand the pathophysiology of the disease and thus to more precisely target the treatment for each patient. To achieve this goal, a systematic search for new, reliable and stable biomarkers specific for each phenotype is essential. This review focuses on the current known molecular phenotypes of severe asthma and highlights the need for biomarkers that could (either alone or in combination) be predictive of the treatment outcome.