Management of severe asthma: a European Respiratory Society/American Thoracic Society guideline

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.

Severe asthma in children: Description of a large multidisciplinary clinical cohort

BACKGROUND

Children with severe asthma have substantial morbidity and healthcare utilization. Pediatric severe asthma is a heterogeneous disease, and a multidisciplinary approach can improve the diagnosis and management of these children.

METHODS

We reviewed the electronic health records for patients seen in the Severe Asthma Clinic (SAC) at UPMC Children's Hospital of Pittsburgh between August 2012 and October 2019.

RESULTS

Of the 110 patients in whom we extracted data, 46% were female, 48% were Black/African American, and 41% had ≥1 admission to the pediatric intensive care unit (PICU) for asthma. Compared to patients without a PICU admission, those with ≥1 PICU admission were more likely to be non-White (64.4% vs. 41.5%, p = 0.031) and more atopic (eosinophil count geometric mean = 673 vs. 319 cells/mm3 , p = 0.002; total IgE geometric mean = 754 vs. 303 KU/L, p = 0.003), and to have lower pre-bronchodilator FEV1 (58.6% [±18.1%] vs. 69.9% [±18.7%], p = 0.002) and elevated FeNO (60% vs. 22%, p = 0.02). In this cohort, 84% of patients were prescribed high-dose ICS/LABA and 36% were on biologics. Following enrollment in the SAC, severe exacerbations decreased from 3.2/year to 2.2/year (p < 0.0001); compared to the year before joining the SAC, in the following year the group had 106 fewer severe exacerbations.

CONCLUSIONS

This large cohort of children with severe asthma had a high level of morbidity and healthcare utilization. Patients with a history of PICU admissions for asthma were more likely to be nonwhite and highly atopic, and to have lower lung function. Our data support a positive impact of a multidisciplinary clinic on patients with severe childhood asthma.

Dupilumab Demonstrates Rapid Onset of Response Across Three Type 2 Inflammatory Diseases

BACKGROUND

Type 2 inflammatory diseases often coexist in patients. Dupilumab targets type 2 inflammation and has demonstrated treatment benefits in patients with atopic dermatitis (AD), asthma, and chronic rhinosinusitis with nasal polyps (CRSwNP) with an acceptable safety profile.

OBJECTIVE

This post hoc analysis across five phase 3 studies in patients with moderate to severe AD or asthma, or severe CRSwNP, evaluated time of onset and duration of the treatment response.

METHODS

Patients received subcutaneous dupilumab 200/300 mg or placebo. Assessments included the Eczema Area and Severity Index, Peak Pruritus Numerical Rating Scale, and Dermatology Life Quality Index in AD; pre-bronchodilator FEV₁, daily morning peak expiratory flow, and symptom scores in asthma; and University of Pennsylvania Smell Identification Test, daily nasal congestion, and loss of smell scores in CRSwNP.

RESULTS

At week 2 after the initiation of dupilumab versus placebo, 67.8% versus 36.5% of AD patients achieved a clinically meaningful benefit (Eczema Area and Severity Index: 50% or greater improvement; Peak Pruritus Numerical Rating Scale: 3 point or greater improvement; or Dermatology Life Quality Index: 4 point or greater improvement) (P < .001). Moreover, 61.6% versus 39.9% of asthma patients achieved improvements in pre-bronchodilator FEV₁ of 100 mL or greater and 48.8% versus 26.3% achieved 200 mL or greater improvement (both P < .001); 33.2% versus 5.6% of CRSwNP patients regained a sense of smell (P < .001). Treatment effects further improved or were sustained to the end of treatment.

CONCLUSIONS

Clinically meaningful responses were achieved rapidly after the first dupilumab dose in AD, asthma, or CRSwNP and were sustained throughout treatment (see Video in this article's Online Repository at www.jaci-inpractice.org).

Characteristics, phenotypes, mechanisms and management of severe asthma

ABSTRACT

Severe asthma is "asthma which requires treatment with high dose inhaled corticosteroids (ICS) plus a second controller (and/or systemic corticosteroids) to prevent it from becoming 'uncontrolled' or which remains 'uncontrolled' despite this therapy." The state of control was defined by symptoms, exacerbations and the degree of airflow obstruction. Therefore, for the diagnosis of severe asthma, it is important to have evidence for a diagnosis of asthma with an assessment of its severity, followed by a review of comorbidities, risk factors, triggers and an assessment of whether treatment is commensurate with severity, whether the prescribed treatments have been adhered to and whether inhaled therapy has been properly administered. Phenotyping of severe asthma has been introduced with the definition of a severe eosinophilic asthma phenotype characterized by recurrent exacerbations despite being on high dose ICS and sometimes oral corticosteroids, with a high blood eosinophil count and a raised level of nitric oxide in exhaled breath. This phenotype has been associated with a Type-2 (T2) inflammatory profile with expression of interleukin (IL)-4, IL-5, and IL-13. Molecular phenotyping has also revealed non-T2 inflammatory phenotypes such as Type-1 or Type-17 driven phenotypes. Antibody treatments targeted at the T2 targets such as anti-IL5, anti-IL5Rα, and anti-IL4Rα antibodies are now available for treating severe eosinophilic asthma, in addition to anti-immunoglobulin E antibody for severe allergic asthma. No targeted treatments are currently available for non-T2 inflammatory phenotypes. Long-term azithromycin and bronchial thermoplasty may be considered. The future lies with molecular phenotyping of the airway inflammatory process to refine asthma endotypes for precision medicine.

Bronchial thermoplasty in severe asthma: a real-world study on efficacy and gene profiling

Background

Bronchial thermoplasty (BT) is an effective treatment in severe asthma. How to select patients who more likely benefit from BT is an unmet clinical need. Moreover, mechanisms of BT efficacy are still largely unknown. We sought to determine BT efficacy and to identify potential mechanisms of response.

Methods

This retrospective cohort study evaluated clinical outcomes in 27 patients with severe asthma: 13 with T2-high and 14 with T2-low endotype. Expression levels of 20 genes were compared by real-time PCR in bronchial biopsies performed at the third BT session versus baseline. Clinical response was measured based on Asthma Control Questionnaire (ACQ) score < 1.5, asthma exacerbations < 2, oral corticosteroids reduction of at least 50% at 12 months post-BT. Patients were classified as responders when they had at least 2 of 3 outcome measures.

Results

81% of patients were defined as responders. BT induced a reduction in alpha smooth muscle actin (ACTA2) and an increase in CD68, fibroblast activation protein-alpha (FAP), alpha-1 and alpha-2 type I collagen (COL1A1, COL1A2) gene expression in the majority of patients. A higher reduction in ubiquitin carboxy-terminal-hydrolase L1 (PGP9.5) mRNA correlated with a better response based on Asthma Quality of Life Questionnaire (AQLQ). Lower changes in CD68 and FAP mRNAs correlated with a better response based on ACQ. Lower levels of occludin (OCLN), CD68, connective tissue growth factor (CTGF), higher levels of secretory leukocyte protease inhibitor (SLPI) and lower changes in CD68 and CTGF mRNAs were observed in patients who had less than 2 exacerbations post-BT. Lower levels of COL1A2 at baseline were observed in patients who had ACQ < 1.5 at 12 months post-BT.

Conclusions

BT is effective irrespective of the asthma endotypes and seems associated with airway remodelling. Quantification of OCLN, CD68, CTGF, SLPI, COL1A2 mRNAs could be useful to identify patients with better results.

Trial registration: The study protocol was approved by the Local Ethics Committee (Azienda USL-IRCCS of Reggio Emilia—Comitato Etico Area Vasta Nord of Emilia Romagna; protocol number: 2019/0014076) and all the patients provided written informed consent before participating in the study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13223-022-00680-4.

Efficacy and Safety of Omalizumab Treatment Over a 16-Year Follow-Up: When a Clinical Trial Meets Real-Life

Purpose

Treatment of severe asthma has made great strides thanks to rapid progress in understanding immune response and inflammatory pathways. This led to the advent of the first biologic for severe allergic asthma (SAA), omalizumab. Although the long-term efficacy and safety of omalizumab has been confirmed, increasingly longer follow-up data can further reinforce this evidence and potentially provide new ones, for example on any loss of efficacy or the appearance of unexpected side effects. This study reports omalizumab treatment-related outcomes after 16 years of follow-up.

Patients and Methods

In this real-life retrospective study, an extension of a previous 9-year follow-up study on patients initially recruited in a clinical trial, we enrolled 8 adult patients with SAA followed-up from November 2005 to December 2021. Study subjects were selected based on omalizumab eligibility criteria.

Results

Exacerbation rate significantly decreased from 3.6 ± 2.1 events in year before index date to 0.1 ± 0.4 after 32 weeks of treatment (p < 0.0001). Mean annual number of mild-to-moderate exacerbations at 16 years was 0.88 compared with 1.8 in the year before the index date and 1.1 at 32 weeks. No hospitalizations were documented during the 16-year follow-up compared to 0.3 hospitalizations/patient in the year before the index date. Respiratory function also progressively and significantly improved. Regarding patient-reported outcomes (PROs), The AQLQ and ACT significantly improved from baseline throughout the follow-up, particularly up to 9 years of follow-up. During the study, an overall reduction in doses of asthma medications was observed, with a significant OCS-sparing effect.

Conclusion

Our study, the longest clinical follow-up on patients treated with anti-IgE, confirms and amplifies the results of the studies carried out so far, as they are maintained over a very long interval of time without drops in efficacy without any type of side effect.

Reliability, Satisfaction and Effectiveness of Benralizumab Home Self-Administration in Patients with Severe Eosinophilic Asthma in Real-World Practice: The Auto-Benra Study

Introduction

The increase in drugs available for severe uncontrolled asthma and the lifestyle of these patients make it necessary to implement self-administration programs of these therapies at home. Benralizumab, a monoclonal antibody targeting IL5R, was authorized in Spain for poorly controlled severe eosinophilic asthma. The possibility of administration at home was approved in March 2020 in Spain. The aim of the Auto-Benra study was to evaluate the usability and satisfaction of the benralizumab prefilled syringe and autoinjector and assessing the effectivity of these devices in uncontrolled severe eosinophilic asthma (SEA) in home-self administration.

Methods

This is a retrospective, observational multicenter study uncontrolled SEA patients treated with benralizumab at least with 3 doses self-administered at home before April 30, 2021. Reliability and satisfaction with benralizumab at home were evaluated with subcutaneous administration assessment questionnaire (SQAAQ) and visual analogic scales (VAS). Effectiveness was evaluated in all patients with asthma control test (ACT), Mini Asthma Quality of Life Questionnaire (MiniAQLQ), annual exacerbation rate, oral corticosteroid treatment (OCS) and asthma-related hospitalizations and emergency visits.

Results

Fifty-four patients across 9 hospitals in Spain were included. The mean SQAAQ score was 6.89 (±0.16) points. Patients and their caregivers and doctors report excellent satisfaction by VAS, with no differences between benralizumab devices used (prefilled syringe and autoinjector). Severe exacerbation rate decreased by 65% (p = 0.0007) after benralizumab treatment. ACT score improved on average 6.27 ± 5.35 points (p < 0.0001) and the mean MiniAQLQ increased up to 1.58 ± 1.47 points (p < 0.0001). Twenty-four patients were OCS-dependent and at the end of study 14 patients get complete OCS withdrawal.

Conclusion

AUTO-BENRA study supports the use of benralizumab at home given the excellent results of satisfaction and usability by patients and their caregivers.

Sex Plays a Multifaceted Role in Asthma Pathogenesis

Sex is considered an important risk factor for asthma onset and exacerbation. The prevalence of asthma is higher in boys than in girls during childhood, which shows a reverse trend after puberty—it becomes higher in adult females than in adult males. In addition, asthma severity, characterized by the rate of hospitalization and relapse after discharge from the emergency department, is higher in female patients. Basic research indicates that female sex hormones enhance type 2 adaptive immune responses, and male sex hormones negatively regulate type 2 innate immune responses. However, whether hormone replacement therapy in postmenopausal women increases the risk of current asthma and asthma onset remains controversial in clinical settings. Recently, sex has also been shown to influence the pathophysiology of asthma in its relationship with genetic or other environmental factors, which modulate asthmatic immune responses in the airway mucosa. In this narrative review, we highlight the role of sex in the continuity of the asthmatic immune response from sensing allergens to Th2 cell activation based on our own data. In addition, we elucidate the interactive role of sex with genetic or environmental factors in asthma exacerbation in women.

T2-low: what do we know?: Past, present, and future of biologic therapies in noneosinophilic asthma

T2-low asthma is an often severe asthma subtype with limited treatment options and biologic therapeutics are lacking. Several monoclonal antibodies (mAbs) targeting non-T2 cytokines were previously reported to be ineffective in asthma. These trials often investigated heterogeneous asthma populations and negative outcomes could be related to unsuitable study cohorts. More tailored approaches in selecting participants based on specific biomarkers have been beneficial in treating severe T2-high asthma. Similarly, mAbs previously deemed ineffective bear the potential to be useful when administered to the correct target population. Here, we review individual clinical trials conducted between 2005 and 2021 and assess the suitability of the selected cohorts, whether study end points were met, and whether outcome measures were appropriate to investigate the effectiveness of the respective drug. We discuss potential target groups within the T2-low asthma population and suggest biomarkers that may predict a treatment response. Furthermore, we assess whether biomarker-guided approaches or subgroup analyses were associated with more positive study outcomes. The mAbs directed against alarmins intervene early in the inflammatory cascade and are the first mAbs found to have efficacy in T2-low asthma. Several randomized controlled trials performed predefined subgroup analyses that included T2-low asthma. Subgroup analyses were associated with positive outcomes and were able to reveal a stronger response in at least 1 subgroup. A better understanding of T2-low subgroups and specific biomarkers is necessary to identify the most responsive target population for a given mAb.

Treatment Resistance in Severe Asthma Patients With a Combination of High Fraction of Exhaled Nitric Oxide and Low Blood Eosinophil Counts

Background: Combining a fraction of exhaled nitric oxide (FeNO) and blood eosinophil count (B-EOS) may be a useful strategy for administration of biologics such as anti-IgE or anti-IL-5 to patients with type 2 inflammatory-predominant severe asthma and is important to be elucidated considering the increasing use of biologics.

Methods: This cross-sectional study analyzed the clinical data from 114 adult patients with severe asthma, who were treated at Saitama Medical University Hospital. The eligible patients were stratified into four subgroups defined by thresholds of FeNO and blood eosinophil (B-EOS) counts to detect sputum eosinophilia, using the receiver operating characteristic curve analysis. A total of 75 patients with optimal samples were stratified into four subtypes defined by thresholds of sputum eosinophilia and neutrophilia. Clinical characteristics, pattern of biologics, and distribution of sputum subtypes were analyzed in the stratified subclasses according to the FeNO and B-EOS thresholds. The asthma exacerbation (AE)-free time of the FeNO/B-EOS subgroups and any biologics treatment including anti-IgE or anti-IL-5 use were examined using the Kaplan–Meier method. The hazard ratios (HRs) for AE-free time were examined using the Cox proportional hazard model.

Results: The optimal cutoff values for prediction of sputum eosinophilia were defined as ≥2.7% wherein for FeNO as ≥27 ppb and B-EOS as ≥265/µL were considered. The high-FeNO subgroups showed significant high total IgE, compared with the low FeNO. The high-FeNO/high-B-EOS and the high-FeNO/low-B-EOS subgroups showed the largest prevalence of mepolizumab and benralizumab use among the other FeNO/B-EOS, respectively. The high-FeNO/low-B-EOS showed the largest frequency of AEs, high HR, and the shortest AE-free time, among the other FeNO/B-EOS. The sputum eosinophil-predominant subtype was the great majority in the high FeNO/high B-EOS. A diverse distribution of sputum leukocyte-predominant subtype was observed in the other FeNO/B-EOS. The subsequent AE-free time and its HR were comparable among the biologics use groups.

Conclusion: The strategy of classifying severe asthma based on the combination of FeNO and B-EOS proposes particular refractory type 2 severe asthma and underlying airway inflammation as a feasible trait for optimal biologics use.

Novel aerosol treatment of airway hyper-reactivity and inflammation in a murine model of asthma with a soluble epoxide hydrolase inhibitor

Asthma currently affects more than 339 million people worldwide. In the present preliminary study, we examined the efficacy of a new, inhalable soluble epoxide hydrolase inhibitor (sEHI), 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), to attenuate airway inflammation, mucin secretion, and hyper-responsiveness (AHR) in an ovalbumin (OVA)-sensitized murine model. Male BALB/c mice were divided into phosphate-buffered saline (PBS), OVA, and OVA+TPPU (2- or 6-h) exposure groups. On days 0 and 14, the mice were administered PBS or sensitized to OVA in PBS. From days 26-38, seven challenge exposures were performed with 30 min inhalation of filtered air or OVA alone. In the OVA+TPPU groups, a 2- or 6-h TPPU inhalation preceded each 30-min OVA exposure. On day 39, pulmonary function tests (PFTs) were performed, and biological samples were collected. Lung tissues were used to semi-quantitatively evaluate the severity of inflammation and airway constriction and the volume of stored intracellular mucosubstances. Bronchoalveolar lavage (BAL) and blood samples were used to analyze regulatory lipid mediator profiles. Significantly (p < 0.05) attenuated alveolar, bronchiolar, and pleural inflammation; airway resistance and constriction; mucosubstance volume; and inflammatory lipid mediator levels were observed with OVA+TPPU relative to OVA alone. Cumulative findings indicated TPPU inhalation effectively inhibited inflammation, suppressed AHR, and prevented mucosubstance accumulation in the murine asthmatic model. Future studies should determine the pharmacokinetics (i.e., absorption, distribution, metabolism, and excretion) and pharmacodynamics (i.e., concentration/dose responses) of inhaled TPPU to explore its potential as an asthma-preventative or -rescue treatment.

Asthma in the Americas: An Update: A Joint Perspective from the Brazilian Thoracic Society, Canadian Thoracic Society, Latin American Thoracic Society, and American Thoracic Society

Asthma affects a large number of people living in the Americas, a vast and diverse geographic region comprising 35 nations in the Caribbean and North, Central, and South America. The marked variability in the prevalence, morbidity, and mortality from asthma across and within nations in the Americas offers a unique opportunity to improve our understanding of the risk factors and management of asthma phenotypes and endotypes in children and adults. Moreover, a better assessment of the causes and treatment of asthma in less economically developed regions in the Americas would help diagnose and treat individuals migrating from those areas to Canada and the United States. In this focused review, we first assess the epidemiology of asthma, review known and potential risk factors, and examine commonalities and differences in asthma management across the Americas. We then discuss future directions in research and health policies to improve the prevention, diagnosis, and management of pediatric and adult asthma in the Americas, including standardized and periodic assessment of asthma burden across the region; large-scale longitudinal studies including omics and comprehensive environmental data on racially and ethnically diverse populations; and dissemination and implementation of guidelines for asthma management across the spectrum of disease severity. New initiatives should recognize differences in socioeconomic development and health care systems across the region while paying particular attention to novel or more impactful risk factors for asthma in the Americas, including indoor pollutants such as biomass fuel, tobacco use, infectious agents and the microbiome, and psychosocial stressor and chronic stress.

The effect of the COVID-19 pandemic on severe asthma care in Europe: will care change for good?

Background

The coronavirus disease 2019 (COVID-19) pandemic has put pressure on healthcare services, forcing the reorganisation of traditional care pathways. We investigated how physicians taking care of severe asthma patients in Europe reorganised care, and how these changes affected patient satisfaction, asthma control and future care.

Methods

In this European-wide cross-sectional study, patient surveys were sent to patients with a physician-diagnosis of severe asthma, and physician surveys to severe asthma specialists between November 2020 and May 2021.

Results

1101 patients and 268 physicians from 16 European countries contributed to the study. Common physician-reported changes in severe asthma care included use of video/phone consultations (46%), reduced availability of physicians (43%) and change to home-administered biologics (38%). Change to phone/video consultations was reported in 45% of patients, of whom 79% were satisfied or very satisfied with this change. Of 709 patients on biologics, 24% experienced changes in biologic care, of whom 92% were changed to home-administered biologics and of these 62% were satisfied or very satisfied with this change. Only 2% reported worsening asthma symptoms associated with changes in biologic care. Many physicians expect continued implementation of video/phone consultations (41%) and home administration of biologics (52%).

Conclusions

Change to video/phone consultations and home administration of biologics was common in severe asthma care during the COVID-19 pandemic and was associated with high satisfaction levels in most but not all cases. Many physicians expect these changes to continue in future severe asthma care, though satisfaction levels may change after the pandemic.

Just breathe: a review of sex and gender in chronic lung disease

Chronic lung diseases are the third leading cause of death worldwide and are increasing in prevalence over time. Although much of our traditional understanding of health and disease is derived from study of the male of the species - be it animal or human - there is increasing evidence that sex and gender contribute to differences in disease risk, prevalence, presentation, severity, treatment approach, response and outcomes. Chronic obstructive pulmonary disease, asthma and bronchiectasis represent the most prevalent and studied chronic lung diseases and have key sex- and gender-based differences which are critical to consider and incorporate into clinical and research approaches. Mechanistic differences present opportunities for therapeutic development whereas behavioural and clinical differences on the part of patients and providers present opportunities for greater education and understanding at multiple levels. In this review, we seek to summarise the sex- and gender-based differences in key chronic lung diseases and outline the clinical and research implications for stakeholders.

Azithromycin inhibits mucin secretion, mucous metaplasia, airway inflammation and airways hyperresponsiveness in mice exposed to house dust mite extract

Excessive production, secretion and retention of abnormal mucus is a pathologic feature of many obstructive airways diseases including asthma, chronic obstructive pulmonary disease, cystic fibrosis and bronchiectasis. Azithromycin is an antibiotic that also possesses immunomodulatory and mucoregulatory activities, which may contribute to the clinical effectiveness of azithromycin in these obstructive airway diseases. The current study investigated these non-antibiotic activities of azithromycin (or saline) in mice exposed daily to intranasal house dust mite (HDM) extract (or SHAM inoculation) for 10 days. HDM-exposed mice exhibited airways hyperresponsiveness to aerosolised methacholine, a pronounced mixed eosinophilic and neutrophilic inflammatory response, increased airway smooth muscle (ASM) thickness and elevated levels of epithelial mucin staining (compared to SHAM mice). Azithromycin (50 mg/kg s.c., 2 h prior to each HDM exposure) significantly attenuated HDM-induced airways hyperresponsiveness to methacholine, airways inflammation (bronchoalveolar lavage eosinophil and neutrophils numbers, and cytokine/chemokine levels), and epithelial mucin staining (mucous metaplasia) (P<0.05, 2-way ANOVA). Isolated tracheal segments of HDM-exposed mice secreted Muc5ac and Muc5b (above baseline levels) in response to exogenous ATP. Moreover, ATP-induced secretion of mucins was significantly attenuated in segments obtained from azithromycin-treated, HDM-exposed mice (P<0.05, 2-way ANOVA). In additional ex vivo studies, ATP-induced secretion of Muc5ac from HDM-exposed tracheal segments was inhibited by in vitro exposure to azithromycin. In vitro azithromycin also inhibited ATP-induced secretion of Muc5ac and Muc5b in tracheal segments from IL-13-exposed mice. In summary, azithromycin inhibited ATP-induced mucin secretion and airways inflammation in HDM-exposed mice, both of which are likely to contribute to suppression of airways hyperresponsiveness.

FeNO is associated with disease burden in the German Asthma Net severe asthma cohort

The fraction of exhaled nitric oxide (F_ENO) is a biomarker for type 2 asthma, reflecting the degree of local pulmonary inflammation linked to immune pathways, including interleukin (IL)-13 [1]. In clinical practice, F_ENO is a reliable marker for inhaled corticosteroid (ICS) responsiveness [2] and the efficacy of biological therapies, such as those targeting IL-4/IL-13 pathways [3, 4], as well as the detection of steroid nonadherence or resistance in severe asthma [2]. The prospective Severe Asthma Registry of the German Asthma Net (GAN) enrols patients with severe asthma for in-depth assessment of phenotypes, underlying mechanisms and therapeutic strategies; GAN has been approved by respective ethics committees, with all included patients having signed informed consent [5]. Prior studies of F_ENO either included patients with asthma of any severity [6] or did not involve a comprehensive analysis in a large cohort [7]. We therefore used cross-sectional data from GAN to determine the correlation of F_ENO with epidemiological, laboratory, clinical, lung function, or quality of life parameters and the need for oral corticosteroid (OCS) maintenance therapy in a carefully selected severe asthma cohort to better characterise the severe asthma subtype with high F_ENO values.

In a severe asthma cohort of 1007 patients, high F_ENO was associated with chronic rhinosinusitis/polyps, later asthma onset, poor lung function and asthma control, low quality of life, frequent exacerbations and the need for maintenance OCS. #GANregistry https://bit.ly/3sNrtIQ

Reply to: Challenging the paradigm

We thank M.L. Everard for his interest in our article [1] and thank the Editors for giving us the opportunity to respond. Space constraints precluded us describing the detailed management of extrapulmonary treatable traits, hence the educational aim was to begin to appreciate, but we are happy to refer interested readers to other review articles on the subject [2–4].

Inhaled corticosteroids should be targeted to those with documented airway eosinophilia, not prescribed indiscriminately to all who wheeze. Blind steroid treatment without regard to underlying pathophysiology is not 21st century standard of care.https://bit.ly/34lyaJG

Allergic and eosinophilic asthma in the era of biomarkers and biologics: similarities, differences and misconceptions

OBJECTIVE

Severe asthma is associated with substantial personal and economic burden; maintaining disease control is the key management goal. Increased understanding of asthma heterogeneity and development of type 2 (T2)-targeting biologics has substantially advanced disease management and outcomes; however, despite both being driven by T2 inflammation, allergic and eosinophilic asthma have different treatment recommendations. We sought to better understand the similarities and differences between allergic and eosinophilic asthma and highlight where misconceptions may arise.

DATA SOURCES

Published articles, pivotal trials, post hoc analyses, and asthma clinical guidelines sourced from PubMed.

STUDY SELECTIONS

Sources reporting allergic and eosinophilic asthma classifications, disease mechanisms, and biomarkers associated with treatment response.

RESULTS

This review highlights that severe allergic and eosinophilic asthma are both driven by T2 inflammation with eosinophils playing a cardinal role. Despite this overlap, treatment recommendations differ based on asthma classification. T2 cytokine gene expression is a reasonably well-established research tool, but not a well-established biomarker in clinical practice, unlike blood eosinophil counts, fractional exhaled nitric oxide, and immunoglobulin E; the clinical relevance of immunoglobulin E as a predictive biomarker remains unclear.

CONCLUSION

Asthma classifications that can be easily characterized at patient level to ensure accurate diagnosis, predict disease trajectory, and treatment response are required. The current dichotomy of allergic and eosinophilic asthma classifications is likely too simplistic, given the similar eosinophil-mediated disease pathophysiology in both classifications. Our results provide future directions to guide clinically meaningful interpretation of asthma endophenotypes, which may improve understanding of severe asthma characterization and aid future advances in defining responders more precisely with personalized medicine approaches.

FeNO in Asthma

Asthma is a common disease affecting 350 million people worldwide, which is characterized by airways inflammation and hyperreactivity. Historically diagnosis and treatment have been mainly based on symptoms, which have the potential to result in misdiagnosis and inappropriate treatment. Nitric oxide (NO) is exhaled in human breath and is a marker of airways inflammation. Levels of NO are increased in the exhaled breath of patients with type 2 asthma and fractional exhaled nitric oxide (FeNO) provides an objective biomarker of airway inflammation. FeNO testing is an accessible, noninvasive, and easy-to-use test. Cut-off values have been established by the American Thoracic Society (ATS), the Global Initiative for Asthma (GINA), and the National Institute for Health and Care Excellence (NICE) but vary between guidance. FeNO levels have been shown to be predictive of blood and sputum eosinophil levels but should not be used in isolation and current guidance emphasizes the importance of incorporating clinical symptoms and testing when utilizing FeNO results. The inclusion of FeNO testing can increase diagnostic accuracy of asthma, while high levels in asthmatic patients can help predict response to inhaled corticosteroids (ICS) and suppression of levels with ICS to monitor adherence. FeNO levels are also a predictor of asthma risk with increased exacerbation rates and accelerated decline in lung function associated with high levels as well as having an emerging role in predicting response to some biologic therapies in severe asthma. FeNO testing is cost-effective and has been shown, when combined with clinical assessment, to improve asthma management.

Use of biologics for the treatment of moderate-to-severe asthma: the age of personalized medicine

PURPOSE OF REVIEW

There are multiple FDA-approved biologics to treat poorly controlled moderate-to-severe asthma. Given the heterogeneity of asthma and the lack of head-to-head data between biologics, selecting the best biologic for a patient can be difficult. This review summarizes the key literature to date, in hopes of facilitating an evidence-based approach to selecting the most appropriate biologic for patients with asthma.

RECENT FINDINGS

In addition to unique mechanisms of action, there is increasing literature on predictors of response to each biologic, such as sensitizations to aeroallergens, peripheral eosinophil count, total serum IgE, and exhaled nitric oxide. Biologics available for asthma are also being increasingly studied in comorbid conditions with asthma, and this may facilitate selecting the most appropriate biologic for a patient. In the absence of head-to-head studies, there is literature of switching between biologics whenever necessary.

SUMMARY

The authors outline an approach to selecting a biologic based on various considerations, and hope this suggested approach facilitates selecting the biologic most suitable for each individual with poorly controlled moderate-to-severe asthma.

Alpine altitude climate treatment for severe and uncontrolled asthma: An EAACI position paper

Currently available European Alpine Altitude Climate Treatment (AACT) programs combine the physical characteristics of altitude with the avoidance of environmental triggers in the alpine climate and a personalized multidisciplinary pulmonary rehabilitation approach. The reduced barometric pressure, oxygen pressure, and air density, the relatively low temperature and humidity, and the increased UV radiation at moderate altitude induce several physiological and immunological adaptation responses. The environmental characteristics of the alpine climate include reduced aeroallergens such as house dust mites (HDM), pollen, fungi, and less air pollution. These combined factors seem to have immunomodulatory effects controlling pathogenic inflammatory responses and favoring less neuro‐immune stress in patients with different asthma phenotypes. The extensive multidisciplinary treatment program may further contribute to the observed clinical improvement by AACT in asthma control and quality of life, fewer exacerbations and hospitalizations, reduced need for oral corticosteroids (OCS), improved lung function, decreased airway hyperresponsiveness (AHR), improved exercise tolerance, and improved sinonasal outcomes. Based on observational studies and expert opinion, AACT represents a valuable therapy for those patients irrespective of their asthma phenotype, who cannot achieve optimal control of their complex condition despite all the advances in medical science and treatment according to guidelines, and therefore run the risk of falling into a downward spiral of loss of physical and mental health. In the light of the observed rapid decrease in inflammation and immunomodulatory effects, AACT can be considered as a natural treatment that targets biological pathways.

Role of Thymus and Activation-Regulated Chemokine in Allergic Asthma

Background

Objective

Methods

Results

Conclusion

Severe and Difficult Asthma: Diagnosis and Management-Challenges for a Low-Resource Environment

Severe and difficult asthma in a low- and middle-income country (LMIC) can relate to (a) lack of availability of basic medications; (b) potentially reversible factors such as poor adherence or comorbidities such as obesity inhibiting a good response to treatment; and (c) (rarely) true severe, therapy-resistant asthma. However, definitions of severity should encompass not merely doses of prescribed medication, but also underlying risk. The nature of asthmatic airway disease shows geographical variation, and LMIC asthma should not be assumed to be phenotypically the same as that in high-income countries (HICs). The first assessment step is to ensure another diagnosis is not being missed. Largely, political action is needed if children with asthma are to get access to basic medications. If a child is apparently not responding to low dose, simple medications, the next step is not to increase the dose but perform a detailed assessment of what factors (for example co-morbidities such as obesity, or social factors like poor adherence) are inhibiting a treatment response; in most cases, an underlying reason can be found. An assessment of risk of future severe asthma attacks, side-effects of medication and impaired lung development is also important. True severe, therapy-resistant asthma is rare and there are multiple underlying molecular pathologies. In HICs, steroid-resistant eosinophilia would be treated with omalizumab or mepolizumab, but the cost of these is prohibitive in LMICs, the biomarkers of successful therapy are likely only relevant to HICs. In LMICs, a raised blood eosinophil count may be due to parasites, so treating asthma based on the blood eosinophil count may not be appropriate in these settings.

The Korean Severe Asthma Registry (KoSAR): real world research in severe asthma

Severe asthma constitutes a serious health burden with significant morbidity and socioeconomic costs. The development and introduction of new biologics targeting type 2 inflammation changed the paradigm for management of severe asthma and initiated a biological era. These changes impose a challenge to clinicians in managing difficult-to-treat and severe asthma. To understand the characteristics and heterogeneity of severe asthma and to develop a better strategy to manage it, the Korean Academy of Asthma, Allergy and Clinical Immunology, Working Group on Severe Asthma, has organized the Korean Severe Asthma Registry (KoSAR). In this review, we describe the challenges of severe asthma management regarding diagnosis, disease burden, heterogeneity, guidelines, and organization of severe asthma clinics. This review also examines the current global activities of national and regional registries and study groups. In addition, we present the KoSAR vision and organization and describe the findings of KoSAR in comparison with those of other countries.

Difficult-to-Treat Asthma Management in School-Age Children

The World Health Organization divides severe asthma into three categories: untreated severe asthma; difficult-to-treat severe asthma; and severe, therapy-resistant asthma. The apparent frequency of severe asthma in the general population of asthmatic children is probably around 5%. Upon referral of these children, it is important to evaluate the diagnosis of asthma carefully before modifying management and applying a long-term monitoring plan. Identification of pathophysiologic phenotypes using objective biomarkers is essential in our routine assessments of severe asthma. Although conventional pharmacologic approaches should be attempted first, there is growing recognition that children with difficult-to-treat asthma may have unique clinical phenotypes that may necessitate alternative treatment approaches including asthma biologics. These new medications, especially those with effects on multiple pathologic features of asthma, raise the hope that new treatment strategies could induce remission. Besides introducing new medications, the opportunity for closer monitoring is feasible with advances in digital health. Therefore, we have the opportunity to improve response to medications, individualize treatment, and monitor response along with potential steps to prevent severe asthma.

Health outcomes after stopping long-term mepolizumab in severe eosinophilic asthma: COMET

Asthma worsening and symptom control are clinically important health outcomes in patients with severe eosinophilic asthma. This analysis of COMET evaluated whether stopping versus continuing long-term mepolizumab therapy impacted these outcomes.

Patients with severe eosinophilic asthma with ≥3 years continuous mepolizumab treatment (via COLUMBA (NCT01691859) or COSMEX (NCT02135692) open-label studies) were eligible to enter COMET (NCT02555371), a randomised, double-blind, placebo-controlled study. Patients were randomised 1:1 to continue mepolizumab 100 mg subcutaneous every 4 weeks or to stop mepolizumab, plus standard of care asthma treatment. Patients could switch to open-label mepolizumab following an exacerbation. Health outcome endpoints included time to first asthma worsening (composite endpoint: rescue use, symptoms, awakening at night and morning peak expiratory flow (PEF)), patient and clinician assessed global rating of asthma severity and overall perception of response to therapy, and unscheduled healthcare resource utilisation.

Patients who stopped mepolizumab showed increased risk of and shorter time to first asthma worsening compared with those who continued mepolizumab (hazard ratio (HR) 1.71; 95% CI 1.17–2.52; p=0.006), including reduced asthma control (increased risk of first worsening in rescue use (HR 1.36; 95% CI 1.00–1.84; p=0.047) and morning PEF (HR 1.77; 95% CI 1.21–2.59; p=0.003). There was a higher probability of any unscheduled healthcare resource use (HR 1.81; 95% CI 1.31–2.49; p<0.001), and patients and clinicians reported greater asthma severity and less favourable perceived response to therapy for patients who stopped versus continued mepolizumab.

These data suggest that patients with severe eosinophilic asthma continuing long-term mepolizumab treatment sustain clinically important improvements in health outcomes.

The COMET study investigated whether stopping long-term mepolizumab had an impact on health outcomes in patients with severe eosinophilic asthma; data suggest those who continue long-term mepolizumab treatment sustain clinically important improvementshttps://bit.ly/3A0bvwu

Mapping atopic dermatitis and anti-IL-22 response signatures to type 2-low severe neutrophilic asthma

BACKGROUND

Transcriptomic changes in patients who respond clinically to biological therapies may identify responses in other tissues or diseases.

OBJECTIVE

We sought to determine whether a disease signature identified in atopic dermatitis (AD) is seen in adults with severe asthma and whether a transcriptomic signature for patients with AD who respond clinically to anti-IL-22 (fezakinumab [FZ]) is enriched in severe asthma.

METHODS

An AD disease signature was obtained from analysis of differentially expressed genes between AD lesional and nonlesional skin biopsies. Differentially expressed genes from lesional skin from therapeutic superresponders before and after 12 weeks of FZ treatment defined the FZ-response signature. Gene set variation analysis was used to produce enrichment scores of AD and FZ-response signatures in the Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes asthma cohort.

RESULTS

The AD disease signature (112 upregulated genes) encompassing inflammatory, T-cell, TH2, and TH17/TH22 pathways was enriched in the blood and sputum of patients with asthma with increasing severity. Patients with asthma with sputum neutrophilia and mixed granulocyte phenotypes were the most enriched (P < .05). The FZ-response signature (296 downregulated genes) was enriched in asthmatic blood (P < .05) and particularly in neutrophilic and mixed granulocytic sputum (P < .05). These data were confirmed in sputum of the Airway Disease Endotyping for Personalized Therapeutics cohort. IL-22 mRNA across tissues did not correlate with FZ-response enrichment scores, but this response signature correlated with TH22/IL-22 pathways.

CONCLUSIONS

The FZ-response signature in AD identifies severe neutrophilic asthmatic patients as potential responders to FZ therapy. This approach will help identify patients for future asthma clinical trials of drugs used successfully in other chronic diseases.

Severe Pediatric Asthma Therapy: Mepolizumab

There is a growing need for advanced treatment in children with persistent and severe asthma symptoms. As a matter of fact, between 2 and 5% of asthmatic children experience repeated hospitalizations and poor quality of life despite optimized treatment with inhaled glucocorticoid plus a second controller. In this scenario, mepolizumab, a humanized monoclonal antibody, has proven to be effective in controlling eosinophil proliferation by targeting interleukin-5 (IL-5), a key mediator of eosinophil activation pathways. Mepolizumab is approved since 2015 for adults at a monthly dose of 100 mg subcutaneously and it has been approved for patients ≥ 6 years of age in 2019. Especially in children aged 6 to 11 years, mepolizumab showed a greater bioavailability, with comparable pharmacodynamics parameters as in the adult population. The recommended dose of 40 mg every 4 weeks for children aged 6 through 11 years, and 100 mg for patients ≥ 12 years provides appropriate concentration and proved similar therapeutic effects as in the adult study group. A marked reduction in eosinophil counts clinically reflects a significant improvement in asthma control as demonstrated by validated questionnaires, reduction of exacerbation rates, and the number of hospitalizations. Finally, mepolizumab provides a safety and tolerability profile similar to that observed in adults with adverse events mostly of mild or moderate severity. The most common adverse events were headache and injection-site reaction. In conclusion, mepolizumab can be considered a safe and targeted step-up therapy for severe asthma with an eosinophilic phenotype in children and adolescents.

Serum Amyloid A1: A Biomarker for Neutrophilic Airway Inflammation in Adult Asthmatic Patients

Purpose

We evaluated the role of serum amyloid A1 (SAA1) in the pathogenesis of airway inflammation according to the phenotype of asthma.

Methods

One hundred twenty-two asthmatic patients and 60 healthy control subjects (HCs) were enrolled to measure SAA1 levels. The production of SAA1 from airway epithelial cells (AECs) and its effects on macrophages and neutrophils were investigated in vitro and in vivo.

Results

The SAA1 levels were significantly higher in sera of asthmatic patients than in those of HCs (P = 0.014); among asthmatics, patients with neutrophilic asthma (NA) showed significantly higher SAA1 levels than those with non-NA (P < 0.001). In vitro, polyinosinic:polycytidylic acid (Poly I-C) treatment markedly enhanced the production of SAA1 from AECs, which was further augmented by neutrophils; SAA1 could induce the production of interleukin (IL)-6, IL-8, and S100 calcium-binding protein A9 from AECs. Additionally, SAA1 activated neutrophils and macrophages isolated from peripheral blood of asthmatics, releasing neutrophil extracellular traps (NETs) and secreting proinflammatory cytokines presenting M1 phenotype, respectively. In ovalbumin-induced asthma mice, Poly I-C treatment significantly increased SAA1 levels as well as IL-17A/interferon-gamma/IL-33 levels in bronchoalveolar lavage fluid (BALF), leading to airway hyperresponsiveness and inflammation. The highest levels of SAA1 and neutrophilia were noted in the BALF and sera of the NA mouse model, followed by the mixed granulocytic asthma (MA) model. Especially, SAA1 induced IL-17/retinoic acid receptor-related orphan receptor γt expression from activated CD4+ T lymphocytes in asthmatic mice.

Conclusions

The results show that SAA1 could induce neutrophilic airway inflammation by activating neutrophils along with NET formation, M1 macrophages, and Th2/Th17 predominant cells, contributing to the phenotype of NA or MA.

A Renewed Charter: Key Principles to Improve Patient Care in Severe Asthma

Asthma is a heterogenous respiratory disease, usually associated with chronic airway inflammation and hyper-responsiveness, which affects an estimated 339 million people worldwide. Severe asthma affects approximately 5-10% of patients with asthma, approximately 17-34 million people globally, more than half of whom have uncontrolled disease. Severe asthma carries a substantial burden of disease, including unpredictable symptoms and potentially life-threatening flare-ups. Furthermore, severe asthma has a substantial burden on health care systems and economies worldwide. In 2018, a group of experts from the clinical community, patient support groups, and professional organisations joined together to develop the Severe Asthma Patient Charter, which set out six principles to define what patients should expect for the management of their severe asthma and what should constitute a basic standard of care. Since the publication of that original Charter in 2018, several important changes have occurred, including an improved understanding of asthma and effective asthma management; several new therapies have become available; and finally, the COVID-19 pandemic has placed a spotlight on respiratory conditions, the workforces that treat them, and the fundamental importance of health care system resilience. With those developments in mind, we, representatives of the academic, clinical, and patient advocacy group communities, have updated the Charter to Improve Patient Care in Severe Asthma with a focus on six principles: (1) I deserve a timely, comprehensive assessment of my asthma and its severity; (2) I deserve a timely, straightforward referral to an appropriate specialist for my asthma when it is not well controlled; (3) I deserve to understand what makes my asthma worse; (4) I deserve access to treatment and care that reduces the impact of asthma on my daily life; (5) I deserve not to be reliant on systemic corticosteroids; (6) I deserve to be involved in decisions about my treatment and care.

How to Choose the Correct Drug in Severe Pediatric Asthma

When a child with severe asthma (asthma defined clinically for the purposes of this review as wheeze, breathlessness, and chest tightness sometimes with cough) does not respond to treatment, it is important to be sure that an alternative or additional diagnosis is not being missed. In school age children, the next step is a detailed protocolized assessment to determine the nature of the problem, whether within the airway or related to co-morbidities or social/environmental factors, in order to personalize the treatment. For example, those with refractory difficult asthma due to persistent non-adherence may benefit from using budesonide and formoterol combined in a single inhaler [single maintenance and reliever treatment (SMART)] as both a reliever and preventer. For those with steroid-resistant Type 2 airway inflammation, the use of biologicals such as omalizumab and mepolizumab should be considered, but for mepolizumab at least, there is a paucity of pediatric data. Protocols are less well developed in preschool asthma, where steroid insensitive disease is much more common, but the use of two simple measurements, aeroallergen sensitization, and peripheral blood eosinophil count, allows the targeted use of inhaled corticosteroids (ICSs). There is also increasing evidence that chronic airway infection may be important in preschool wheeze, increasing the possibility that targeted antibiotics may be beneficial. Asthma in the first year of life is not driven by Type 2 inflammation, so beyond avoiding prescribing ICSs, no evidence based recommendations can be made. In the future, we urgently need to develop objective biomarkers, especially of risk, so that treatment can be targeted effectively; we need to address the scandal of the lack of data in children compared with adults, precluding making evidence-based therapeutic decisions and move from guiding treatment by phenotypes, which will change as the environment changes, to endotype based therapy.

Are serum immunoglobulin concentrations a predictive biomarker of response to anti-IL5/IL5Rα therapies?

BACKGROUND

Approval of biologics has recently revolutionized T2 severe asthma management. However, predictive biomarkers remain highly needed to improve patient's selection.

OBJECTIVE

This study aims to determine whether serum immunoglobulins (Igs) levels might be predictive biomarkers of response to anti-interleukin-5 (IL5)/IL5Rα therapies.

METHODS

Severe asthma patients eligible for mepolizumab or benralizumab were included herein. Serum immunoglobulin quantification was performed at baseline before mepolizumab or benralizumab initiation. After a 6-month treatment of mepolizumab or benralizumab, patients presented a second serum immunoglobulin quantification. The treatment response was evaluated by the GETE (Global Evaluation of Treatment Effectiveness) score at 6 months.

RESULTS

A total of 50 patients were included. Median age was 56 [IQR 48.8-65.3] and 50% were females. Compared to baseline, a significant increase in IgG was observed at 6 months (9.2 [7.8-10.2] g/l vs 10.1 [8.8-11.1] g/l, p = 0.04). The area under the ROC curve was 0.58 [95%IC 0.40-0.77] for blood eosinophil count (p = 0.37), 0.75 [95%IC: 0.58-0.92] for serum IgG concentration (p = 0.009) for predicting the treatment response. According to the Youden index, serum IgG concentration ≥ 9.2 g/l predicts the response to anti-IL5 therapies with a sensitivity of 76.9% and a specificity of 75.7%.

CONCLUSION

Baseline serum IgG concentrations may be a useful tool to predict the response to anti-IL5/IL5Rα therapies but should be confirmed in larger clinical trials. Interestingly, anti-IL5/IL5Rα therapies are associated with a significant increase in serum IgG concentrations at 6 months.

A bird's eye view on the role of dendritic cells in SARS-CoV-2 infection: Perspectives for immune-based vaccines

Coronavirus disease-19 (COVID-19) is a complex disorder caused by the pandemic diffusion of a novel coronavirus named SARS-CoV-2. Clinical manifestations vary from silent infection to severe pneumonia, disseminated thrombosis, multi-organ failure, and death. COVID-19 pathogenesis is still not fully elucidated, while increasing evidence suggests that disease phenotypes are strongly related to the virus-induced immune system's dysregulation. Indeed, when the virus-host cross talk is out of control, the occurrence of an aberrant systemic inflammatory reaction, named "cytokine storm," leads to a detrimental impairment of the adaptive immune response. Dendritic cells (DCs) are the most potent antigen-presenting cells able to support innate immune and promote adaptive responses. Besides, DCs play a key role in the anti-viral defense. The aim of this review is to focus on DC involvement in SARS-CoV-2 infection to better understand pathogenesis and clinical behavior of COVID-19 and explore potential implications for immune-based therapy strategies.

Oral corticosteroid-sparing effects of mepolizumab in severe eosinophilic asthma: evidence from randomized controlled trials and real-world studies

Oral corticosteroids (OCS) have long been a mainstay of treatment for asthma exacerbations and chronic severe asthma. However, it is increasingly recognized that both long-term and short-term OCS use are directly associated with a wide range of serious adverse effects, and as such OCS-sparing treatment alternatives are now widely recommended for patients with severe asthma. While several international guidelines recommend these treatments, guidance on OCS tapering, and which patients are most likely to tolerate OCS reduction and/or discontinuation, is still lacking. Several biologics have demonstrated efficacy in patients with OCS-dependent asthma. One OCS-sparing treatment is the anti-interleukin-5 monoclonal antibody mepolizumab, which is approved for the treatment of severe eosinophilic asthma. In addition to improved exacerbation rates, asthma control, quality of life, and lung function among patients with severe eosinophilic asthma, mepolizumab also has an OCS-sparing effect, which has been demonstrated in randomized controlled trials and real-world studies. Both physicians and patients express concerns about the adverse effects of OCS, and additional data from the randomized, controlled SIRIUS trial (NCT01691508) highlight the high level of concern among patients regarding OCS-related burden. In this article, we discuss current guidance on OCS-sparing strategies for patients with severe asthma, provide a summary of the available evidence of the OCS-sparing effect of mepolizumab, and highlight patient and physician perspectives on the use of OCS and OCS-sparing treatments in severe asthma.

Allergen immunotherapy in treating allergic eosinophilic asthma

Currently, the approach to a patient with asthma is in accordance with personalized medicine wherein the decision on the treatment pathway is based on the type of asthmatic inflammation and other comorbidities that accompany asthma. For an allergic asthma patient, allergen immunotherapy (AIT), which has a disease-modifying effect and the potential to prevent further progression of allergic symptoms, is one of the treatment modalities. It is an effective treatment that, unlike pharmacotherapy, modifies the course of allergic respiratory diseases and induces allergen specific immune tolerance that persists for up to several years after treatment cessation. Therapeutic allergens of high quality, efficacy, and safety according to European regulatory authorities are an integral part of the treatment of respiratory allergies. It is a safe treatment option which still remains the only causal immuno¬modulatory therapy for allergic eosinophilic asthma.

Update on Long-Acting Anticholinergics in Children and Adolescents With Difficult and Severe Asthma

Tiotropium bromide is the only long-acting muscarinic antagonist (LAMA) approved for treatment of patients aged ≥6 years old who have symptoms of uncontrolled asthma. Results from several clinical trials have found that once-daily inhaled tiotropium bromide is safe and efficacious in 6- to 17-year-olds with symptomatic asthma despite treatment with inhaled corticosteroids, with or without other medications. There are still few available studies investigating the impact of tiotropium bromide treatment in preschool children with suboptimal control. In this narrative review, we summarize the pharmacological effects of the LAMA tiotropium bromide, provide an overview about current asthma studies at different pediatric ages, and describe future research needs.

The A118G single-nucleotide polymorphism in OPRM1 is a risk factor for asthma severity

BACKGROUND

Although population studies have implicated emotional burden in asthma severity, the underlying genetic risk factors are not completely understood. We aimed to evaluate the genetic influence of a functional single-nucleotide polymorphism (SNP) in the stress-related μ-opioid receptor gene (OPRM1; A118G SNP, rs1799971) on asthma severity.

METHODS

We initially assessed disease severity in asthmatic outpatients carrying A118G. Using an ovalbumin-induced experimental asthma rodent model harboring the functionally equivalent SNP, we investigated the mechanism by which this SNP influences the allergic immune response.

RESULTS

Among 292 outpatients, 168 underwent airway hyperresponsiveness (AHR) to methacholine testing. Compared with patients carrying the AA and AG genotypes, those carrying the GG genotype exhibited enhanced AHR. The stress levels were presumed to be moderate among patients and were comparable among genotypes. Compared with Oprm1 AA mice, GG mice demonstrated aggravated asthma-related features and increased pulmonary interleukin-4⁺CD4⁺ effector and effector memory T cells under everyday life stress conditions. Intraperitoneal naloxone methiodide injection reduced effector CD4⁺ T cell elevation associated with increased eosinophil numbers in bronchoalveolar lavage fluid of GG mice to the levels in AA mice, suggesting that elevated Th2 cell generation in the bronchial lymph node (BLN) of GG mice induces enhanced eosinophilic inflammation.

CONCLUSIONS

Without forced stress exposure, patients with asthma carrying the OPRM1 GG genotype exhibit enhanced AHR, attributable to enhanced Th2 cell differentiation in the regional lymph node. Further research is necessary to elucidate the role of the OPRM1 A118G genotype in the Th2 cell differentiation pathway in the BLN.

Considering biomarkers in asthma disease severity

Amongst patients with asthma, reliance on the type/dose of prescribed medication and symptom control does not adequately capture those at risk of adverse outcomes, and we need biomarkers for risk and treatment stratification which are consistently accurate, readily quantifiable and reproducible. The majority of patients with severe asthma, regardless of age, have predominant type-2 (T2) inflammation mediated disease, making airway/blood eosinophils, FeNO, periostin and/or allergic sensitization potentially important biomarkers for severe disease. In both adult and pediatric asthma, there is scope to improve prediction of severe attacks by using a composite T2 biomarkers of blood eosinophils and FeNO. Technological advances in component-resolved diagnostics (CRD) microarray technologies coupled with the development of interpretation software offer a possibility to use CRD as biomarkers of asthma severity amongst sensitized asthmatics. Genetic predisposition and polygenic risk scores of relevant traits (e.g., lung function, host immune responses, biomarkers of exposure from the indoor and outdoor environment, infection and microbial dysbiosis) may also contribute to prediction algorithms. We challenge the idea that asthma can be accurately defined in an individual patient by a discrete and static "endotype" (e.g., T2-high asthma). As we traverse the new era of molecular endotyping in asthma, we need to understand how relevant mechanisms impact patient outcomes, and in parallel develop new tools and approaches to stratify therapies and define individual patient trajectories.

Real-world study in severe eosinophilic asthma patients refractory to anti-IL5 biological agents treated with benralizumab in Spain (ORBE study)

Background

Benralizumab, a monoclonal antibody targeting the human interleukin-5 (IL-5) receptor (IL-5R), was used before marketing authorisation in Spain in a real world setting as part of an early-access programme (EAP) to treat patients with severe eosinophilic asthma with prior insufficient response or intolerance to anti-IL5 treatment (mepolizumab or reslizumab). The objective of this study is to describe the patient profile candidate for treatment and to assess benralizumab effectiveness.

Methods

This is an observational, retrospective, multicentre study in severe eosinophilic asthma patients refractory to other biological agents targeting the IL-5 pathway. Baseline characteristics included closest data, from the previous 12 months, to benralizumab treatment onset (index date). Patients were followed until the last treatment dosage while EAP was active (March to December 2018). Effectiveness was evaluated versus baseline, in patients who received at least three doses, with asthma control test (ACT), Mini Asthma Quality of Life Questionnaire (MiniAQLQ), annual severe exacerbation rate, oral corticosteroids treatment (OCS) and asthma-related healthcare resources utilization.

Results

Twenty-seven patients treated with benralizumab were included in the analysis. Effectiveness was assessed in 19 patients. Both questionnaires showed clinically meaningful differences, i.e. ACT score ≥ 3 and MiniAQLQ score ≥ 0.5, compared with baseline [mean (SD), 3.3 (6.8) and 1.2 (1.9), respectively]. Patients treated with OCS decreased during follow-up from 88.9% (n = 24/27) at baseline to 78.9% (n = 15/19) and 31.6% (n = 6/19) had an OCS dose reduction ≥ 50%. The difference in annual severe exacerbation rate during follow-up showed a significant reduction vs. baseline (2.12 per patient-year, 95% CI 0.99–3.24, p = 0.002). The differences in annual rate of non-scheduled primary care and specialist visits during follow-up indicated a significant decrease [2.28 per patient-year (95% CI 1.55–3.01; p < 0.001) and 1.47 per patient-year (95% CI 0.65–2.30; p = 0.004), respectively], as well as the difference in annual rate of number of emergency department visits [1.18 per patient-year (95% CI 0.51–1.85; p = 0.007)].

Conclusions

These results suggest that severe eosinophilic asthma patients receiving benralizumab, presented clinically meaningful improvement in asthma control and asthma-related QoL as well as OCS dose reduction. Results also aim to significant reductions in annual severe exacerbation rates, non-scheduled primary care and specialist visits, and emergency department visits rates.

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.