Optimal management of severe/refractory asthma

Treatment by biomarker-informed endotype vs guideline care in children with difficult-to-treat asthma

BACKGROUND

Asthma is heterogeneous, contributing to difficulty in disease management.

OBJECTIVE

To develop a biomarker-informed treatment model for difficult-to-treat (DTT) asthma and conduct a pilot feasibility study.

METHODS

School-aged children (n = 21) with DTT asthma were enrolled and completed 3 medical visits (V1-V3). V2 and V3 were completed approximately 3.5 months and 12 months after V1, respectively. At V1, guideline care and adherence interventions were initiated, and blood samples were collected for asthma biomarker assessment. A personalized treatment algorithm was developed based on biomarkers (treatment by endotype) and was implemented at V2. Asthma outcomes were compared from V1 to V2 (guideline-based care) to V2 to V3 (guideline + biomarker-informed care).

RESULTS

Overall retention was 86%. There was an even distribution of participants with allergy, without allergy, and with mixed allergies. The participants received an average of 5.9 interventions (range, 3-9). The allergic phenotype was characterized by increased CDHR3 risk genotype and high transepidermal water loss. High serum interleukin-6 level was most notable in the mixed allergic subgroup. The nonallergic phenotype was characterized by vitamin D deficiency and poor steroid treatment responsiveness. The personalized treatment plans were associated with decreased emergency department visits (median, 1 vs 0; P = .04) and increased asthma control test scores (median, 22.5 vs 23.0; P = .01).

CONCLUSION

The biomarker-based treatment algorithm triggered interventions on top of guideline care in all children with DTT asthma studied, supporting the need for this type of multipronged approach. Our findings identify the minimal biomarker set that is informative, reveal that this treatment-by-endotype intervention is feasible and may be superior to guideline care alone, and provide a strong foundation for a definitive trial.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04179461.

Defining type 2 asthma and patients eligible for dupilumab in Italy: a biomarker-based analysis

Background

Asthma is a chronic disease characterized by airway hyperresponsiveness, inflammation and mucus production. In Type 2 asthma, two phenotypic components are often co-expressed (eosinophilic and allergic). Elevated biomarker levels, such as eosinophils (EOS), fraction of exhaled nitric oxide (FeNO) and immunoglobulin E (IgE), are key clinical indicators of Type 2 inflammation. Dupilumab has been recently approved for the treatment of uncontrolled severe Type 2 asthma. Type 2 asthma includes allergic and/or eosinophilic phenotypes. The aim of this analysis was to estimate the dupilumab-eligible population in Italy and characterize it by expected biomarker status.

Methods

A 4-step approach was carried out to calculate dupilumab-eligible population. The approach consisted in: (1) estimating the total number of asthma patients in Italy (using 2016–2017 Italian-adapted Global Initiative for Asthma -GINA- guidelines); (2) estimating the number of severe asthma patients with poorly controlled or uncontrolled disease (using the findings of two recent administrative claim analyses conducted in Italy); (3) stratifying the severe uncontrolled population by biomarker levels (EOS, FeNO and IgE) according to the outcomes of the QUEST trial (a clinical study assessing the efficacy of dupilumab in patients with uncontrolled moderate-to-severe asthma; NCT02414854); (4) identifying the sub-populations of severe uncontrolled asthma patients characterised by raised blood EOS and/or FeNO level (thus indicated to receive dupilumab).

Results

According to these estimates, about 3.3 million asthmatic patients live in Italy (6.10% of the population). Of them, almost 20 thousand (N = 19,960) have uncontrolled severe asthma. Dupilumab-eligible patients would be N = 15,988, corresponding to 80.1% of the total uncontrolled severe population. Most of these patients (89.3%; N = 14,271) have at least an increase of EOS level, while slightly more than half (51.9%; N = 8,303) have raised levels of both biomarkers. Increased FeNO levels without increased EOS are observed less frequently (N = 1,717; 10.7% of the eligible population).

Conclusions

There is a strong rationale for testing all asthma biomarkers during diagnosis and disease follow-up. Given the large availability and the limited costs, these tests are cost-effective tools to detect severe Type 2 asthma, stratify patients by phenotype, and drive appropriate treatment decisions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12948-021-00146-9.

Diagnosis and Management of Severe Asthma in Switzerland: Analysis of Survey Results Conducted with Specialists and General Practitioners

BACKGROUND

Severe asthma commonly affects 5-10% of the asthmatic population and accounts for approximately 50% of the overall asthma costs.

OBJECTIVE

This analysis investigated how severe asthma is diagnosed, treated, and managed by specialists and general practitioners (GPs) in Switzerland.

METHODS

Two surveys, one each among specialists (N = 44) and GPs (N = 153), were conducted to understand their self-perception on diagnosis, treatment, and management of severe asthma.

RESULTS

Fifty-five percent of the specialists felt very confident and 43% confident in recognizing the symptoms of severe asthma and diagnosing severe asthma. In contrast, 9% of the GPs were very confident and 59% confident in diagnosing severe asthma. More specific diagnostic tests for severe asthma, like total and specific immunoglobulin E levels and measurement of the fraction of exhaled nitric oxide, were run by specialists (χ2 = 171.4; df = 15, p < 0.001). GPs and specialists were using different measurements to assess severe asthma (χ2 = 385.2; df = 13, p < 0.001) and their prescribing patterns differed significantly (χ2 = 189.8; df = 10, p < 0.001). GPs referred patients with severe asthma if the diagnosis was unclear (24%), if treatment failure occurred (26%), and if the patients were at high risk (41%).

CONCLUSIONS

Oral corticosteroids (OCSs) are considered as background therapy for severe asthma by GPs and specialists. In order to reduce the OCS burden, there is a need to improve the awareness for other add-on therapies. A joint collaboration between GPs and specialists is the key to leverage therapeutic strategies together.

Immunologic Pathophysiology and Airway Remodeling Mechanism in Severe Asthma: Focused on IgE-Mediated Pathways

Despite the expansion of the understanding in asthma pathophysiology and the continual advances in disease management, a small subgroup of patients remains partially controlled or refractory to standard treatments. Upon the identification of immunoglobulin E (IgE) and other inflammatory mediators, investigations and developments of targeted agents have thrived. Omalizumab is a humanized monoclonal antibody that specifically targets the circulating IgE, which in turn impedes and reduces subsequent releases of the proinflammatory mediators. In the past decade, omalizumab has been proven to be efficacious and well-tolerated in the treatment of moderate-to-severe asthma in both trials and real-life studies, most notably in reducing exacerbation rates and corticosteroid use. While growing evidence has demonstrated that omalizumab may be potentially beneficial in treating other allergic diseases, its indication remains confined to treating severe allergic asthma and chronic idiopathic urticaria. Future efforts may be bestowed on determining the optimal length of omalizumab treatment, seeking biomarkers that could better predict treatment response and as well as extending its indications.

COVID-19 and clinical neuropsychology: A review of neuropsychological literature on acute and chronic pulmonary disease

Objective: The illness resulting from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), better known as COVID-19, has quickly escalated to a worldwide pandemic. Although understanding of the short and long-term manifestations of COVID-19 remains incomplete, there is a preponderance of respiratory pathology in COVID-19 and potential for chronic loss of pulmonary function in recovered patients, raising concerns for associated cognitive impacts.Method: We conducted a narrative review of the existing literature on neuropsychological variables in acute/severe respiratory disease and various forms of chronic pulmonary disease to inform expectations about potential cognitive manifestations of COVID-19.Results: Cognitive dysfunction is common but not inevitable in acute and chronic pulmonary disease, although unique predictors and symptom trajectories appear to be associated with each.Conclusions: Although the full scope of neuropathophysiology associated with COVID-19 remains to be established, pulmonary insults associated with the disease are likely to produce cognitive dysfunction in a substantial percentage of patients.

Treatment Benefit with Omalizumab in Children by Indicators of Asthma Severity

BACKGROUND

Greater severity in childhood asthma negatively impacts functioning and quality of life. Omalizumab is effective in children aged 6 years or older with moderate to severe persistent asthma, but predicting responsiveness in severe disease requires further study.

OBJECTIVE

To assess response to omalizumab treatment among children using indicators of asthma severity.

METHODS

Post hoc analyses of randomized placebo-controlled studies of omalizumab (Inner-City Anti-IgE Therapy for Asthma [ICATA], IA05, and Preventative Omalizumab or Step-up Therapy for Fall Exacerbations [PROSE]) stratified by body mass index, eosinophil count, fractional exhaled nitric oxide levels, and baseline severity indicators (baseline percent predicted FEV₁, previous hospitalizations, asthma exacerbations). Poisson regression analysis examined exacerbation rate reductions for body mass index, biomarkers, and severity indicators.

RESULTS

Children aged 6 to 11 years in IA05 (N = 576; 56% white, 17% black, 26% other/missing), ICATA (N = 237; 55% black, 43% Hispanic), and PROSE (N = 342; 59% black, 35% Hispanic) were included. Trends indicative of greater exacerbation rate change ([omalizumab - placebo]/placebo) were observed for low baseline lung function (IA05 percent predicted FEV₁: <90%, 36% reduction, 95% CI, -53.3 to -13.5; ≥90%, 22% reduction, 95% CI, -52.1 to 27.5), previous hospitalizations (ICATA: 46% reduction with, 95% CI, -69.7 to -3.9; 24% reduction without, 95% CI, -48.1 to 10.3), frequent baseline exacerbations (IA05: ≥3, 42% reduction, 95% CI, -60.4 to -14.1; <3, 20% reduction, 95% CI, -45.2 to -15.9), and high baseline eosinophil count (IA05: ≥300 cells/μL, 39% reduction, 95% CI, -56.4 to -14.7; <300 cells/μL, 5% reduction, 95% CI, -40.6 to 52.1).

CONCLUSIONS

Omalizumab reduces exacerbations in children with moderate to severe persistent allergic asthma, and may provide greater benefit in children with more severe asthma subtypes.

Disease Burden and Long-Term Risk of Persistent Very Poorly Controlled Asthma: TENOR II

BACKGROUND

Severe/difficult-to-treat disease occurs in 5% to 10% of patients with asthma, but accounts for more than 50% of related economic costs. Understanding factors associated with persistent very poorly controlled (VPC) asthma may improve outcomes.

OBJECTIVE

To characterize persistent VPC asthma after more than 10 years of standard of care.

METHODS

The Epidemiology and Natural history of asthma: Outcomes and treatment Regimens (TENOR) II (N = 341) was a multicenter, observational study of patients with severe/difficult-to-treat asthma with a single, cross-sectional visit more than 10 years after TENOR I. Persistent VPC asthma was defined as VPC asthma at TENOR I and TENOR II enrollment; without VPC asthma was defined as well- or not well-controlled asthma at either or both visits. Multivariable logistic regression assessed long-term predictors of persistent VPC asthma using TENOR I baseline variables.

RESULTS

Of 327 patients, nearly half (48.0%, n = 157) had persistent VPC asthma. Comorbidities and asthma triggers were more frequent in patients with persistent VPC asthma than in patients without VPC asthma. Total geometric mean IgE was higher in patients with persistent VPC asthma (89.3 IU/mL vs 55.7 IU/mL); there was no difference in eosinophil levels. Lung function was lower in patients with persistent VPC asthma (mean % predicted pre- and postbronchodilator FEV₁, 63.0% vs 82.8% and 69.6% vs 87.2%, respectively). Exacerbations in the previous year were more likely in patients with persistent VPC asthma (29.7% vs 9.0%, respectively). Predictors of persistent VPC asthma were black versus white race/ethnicity, allergic trigger count (4 vs 0), systemic corticosteroid use, and postbronchodilator FEV₁ (per 10% decrease).

CONCLUSIONS

The burden of persistent VPC asthma is high in severe/difficult-to-treat disease; management of modifiable risk factors, maximization of lung function, and trigger avoidance may improve outcomes.

Airway epithelial-targeted nanoparticles for asthma therapy

Asthma is a common chronic inflammatory disease associated with intermittent airflow obstruction caused by airway inflammation, mucus overproduction, and bronchial hyperresponsiveness. Despite current treatment and management options, a large number of patients with asthma still have poorly controlled disease and are susceptible to acute exacerbations, usually caused by a respiratory virus infection. As a result, there remains a need for novel therapies to achieve better control and prevent/treat exacerbations. Nanoparticles (NPs), including extracellular vesicles (EV) and their synthetic counterparts, have been developed for drug delivery in respiratory diseases. In the case of asthma, where airway epithelium dysfunction, including dysregulated differentiation of epithelial cells, impaired barrier, and immune response, is a driver of disease, targeting airway epithelial cells with NPs may offer opportunities to repair or reverse these dysfunctions with therapeutic interventions. EVs possess multiple advantages for airway epithelial targeting, such as their natural intrinsic cell-targeting properties and low immunogenicity. Synthetic NPs can be coated with muco-inert polymers to overcome biological barriers such as mucus and the phagocytic response of immune cells. Targeting ligands could be also added to enhance targeting specificity to epithelial cells. The review presents current understanding and advances in NP-mediated drug delivery to airway epithelium for asthma therapy. Future perspectives in this therapeutic strategy will also be discussed, including the development of novel formulations and physiologically relevant preclinical models.

Cost-effectiveness of fractional exhaled nitric oxide (FeNO) measurement in predicting response to omalizumab in asthma

Purpose: To use a modeled analysis to examine the cost-effectiveness of utilizing fractional exhaled nitric oxide (FeNO) as a biomarker to aid in the identification of omalizumab responders in patients with moderate-to-severe allergic asthma. Omalizumab is a biological drug used to treat asthma in adults and children 12 years and older. Patients and methods: We conducted a decision analysis in which two alternative strategies for predicting omalizumab response were assessed: 1) testing response via a 12-week trial of omalizumab and 2) using FeNO measurement to screen patients for likely omalizumab response prior to initiating a 12-week trial of omalizumab. In the standard of care arm, trial omalizumab responders continue on to receive 12 months of continuous omalizumab therapy. In the FeNO measurement predictor arm, patients with FeNO measurements >19.5 ppb are started on a trial of omalizumab. Trial omalizumab responders in this arm are then also tracked for 12 months of continuous omalizumab therapy. Results: Per-patient costs during the trial and initial treatment periods total $10,943 for FeNO + omalizumab and $13,703 for omalizumab only. The expected cost per responder during the trial period is $4,326 for FeNO + omalizumab and $7,786 for omalizumab only. Conclusion: Use of FeNO measurement to identify omalizumab responders decreases the expected per-patient cost by nearly 50% during the trial period and continues to show cost savings through the initial treatment period of 12 months. Our analysis may serve as a model for policy and clinical practice regarding the use of FeNO to determine omalizumab response and has widespread implications for health care payers, who may choose to require FeNO measurement and prespecify a minimum FeNO value to determine patient eligibility for omalizumab trial.

Efficacy and steroid-sparing effect of benralizumab: has it an advantage over its competitors?

Severe refractory asthma is characterized by a higher risk of asthma-related symptoms, morbidities, and exacerbations. This disease also determines much greater healthcare costs and deterioration in health-related quality of life (HR-QoL). Another concern, which is currently much discussed, is the high percentage of patients needing regular use of oral corticosteroids (OCS), which can lead to several systemic side effects. Airway eosinophilia is present in the majority of asthmatic patients, and elevated levels of blood and sputum eosinophils are associated with worse control of asthma. Regarding severe refractory eosinophilic asthma, interleukin-5 (IL-5) plays a fundamental role in the inflammatory response, due to the profound effect on eosinophils biology. The advent of the biological therapies provided an effective strategy, even if the increased number of molecules with different targets raised the challenge of choosing the right therapy and avoid overlapping. When considering severe refractory eosinophilic asthma and anti-IL-5 treatments, it is not easy to define which drug to choose between mepolizumab, reslizumab, and benralizumab.

In this article, we carried out an indirect comparison among literature data, especially between OCS reduction studies (ZONDA-SIRIUS) and pivotal studies (SIROCCO-MENSA), evaluating whether the clinical efficacy and the steroid-sparing effect of benralizumab may represent an advantage over other compounds. This data could help the clinician in the decision process of treatment choice, within the different available therapeutic options for eosinophilic refractory severe asthma.

Severe refractory asthma: current treatment options and ongoing research

Patients with severe asthma have a greater risk of asthma-related symptoms, morbidities, and exacerbations. Moreover, healthcare costs of patients with severe refractory asthma are at least 80% higher than those with stable asthma, mainly because of a higher use of healthcare resources and chronic side effects of oral corticosteroids (OCS). The advent of new promising biologicals provides a unique therapeutic option that could achieve asthma control without OCS. However, the increasing number of available molecules poses a new challenge: the identification and selection of the most appropriate treatment. Thanks to a better understanding of the basic mechanisms of the disease and the use of predictive biomarkers, especially regarding the Th2-high endotype, it is now easier than before to tailor therapy and guide clinicians toward the most suitable therapeutic choice, thus reducing the number of uncontrolled patients and therapeutic failures. In this review, we will discuss the different biological options available for the treatment of severe refractory asthma, their mechanism of action, and the overlapping aspects of their usage in clinical practice. The availability of new molecules, specific for different molecular targets, is a key topic, especially when considering that the same targets are sometimes part of the same phenotype. The aim of this review is to help clarify these doubts, which may facilitate the clinical decision-making process and the achievement of the best possible outcomes.

Omalizumab for Severe Asthma: Beyond Allergic Asthma

Different subsets of asthma patients may be recognized according to the exposure trigger and the frequency and severity of clinical signs and symptoms. Regarding the exposure trigger, generally asthma can be classified as allergic (or atopic) and nonallergic (or nonatopic). Allergic and nonallergic asthma are distinguished by the presence or absence of clinical allergic reaction and in vitro IgE response to specific aeroallergens. The mechanisms of allergic asthma have been extensively studied with major advances in the last two decades. Nonallergic asthma is characterized by its apparent independence from allergen exposure and sensitization and a higher degree of severity, but little is known regarding the underlying mechanisms. Clinically, allergic and nonallergic asthma are virtually indistinguishable in exacerbations, although exacerbation following allergen exposure is typical of allergic asthma. Although they both show several distinct clinical phenotypes and different biomarkers, there are no ideal biomarkers to stratify asthma phenotypes and guide therapy in clinical practice. Nevertheless, some biomarkers may be helpful to select subsets of atopic patients which might benefit from biologic agents, such as omalizumab. Patients with severe asthma, uncontrolled besides optimal treatment, notwithstanding nonatopic, may also benefit from omalizumab therapy, although currently there are no randomized double-blind placebo controlled clinical trials to support this suggestion. However, omalizumab discontinuation according to each patient's response to therapy and pharmacoeconomical analysis are questions that remain to be answered.

Nanoparticle-based CpG-oligonucleotide therapy for treating allergic asthma

Allergic asthma is becoming increasingly prevalent in the developed world, and many common allergens are capable of inducing allergic asthma responses, particularly in atopic individuals. Unmethylated CpG-oligonucleotide (ODN) therapy can shift the immune response to mitigate these allergic responses. Therapeutic and prophylactic delivery of soluble CpG-ODN in preclinical studies has shown promise in treating existing asthma and preventing allergic responses upon subsequent allergen exposure, respectively. However, when CpG-ODN is coupled with nanoparticles or self assembled into nanostructures, improved efficacy of CpG-ODN treatment for several common allergens is observed in preclinical studies and clinical trials. Here we discuss the role of CpG-ODN in treating allergic asthma and how nanoparticle-based delivery can further enhance its therapeutic properties.

Alternative approaches for the treatment of airway diseases: focus on nanoparticle medicine

Despite the various treatment options and international guidelines currently available for the appropriate therapeutic management of asthma, a large population of patients with asthma continues to have poorly controlled disease. There is therefore a need for novel approaches to achieve better asthma control, especially for severe asthmatics. This review discusses the use of nanoparticles for the specific targeting of inflammatory pathways as a promising approach for the effective control of severe persistent asthma as well as other chronic inflammatory diseases.

The role of airway hyperresponsiveness measured by methacholine challenge test in defining asthma severity in asthma-obesity syndrome

PURPOSE OF REVIEW

Asthma is a complex disease defined by chronic inflammation of the airways. In research and clinical practice measures used for diagnosis, an assessment of control and severity of asthma are varied and there exists no gold standard. To date, several studies have explored the link between obesity and asthma although the exact mechanism is not yet fully understood. A study undertaken by our research group in 2015, on the effects of weight loss on asthma severity in obese asthmatics, demonstrated that an improvement in airway hyperresponsiveness could be achieved after significant weight reduction with a weight loss program. The objective of this article is to review the current literature for the primary and secondary outcomes studied to estimate the effects of weight loss on asthma severity in adults with obesity and asthma.

RECENT FINDINGS

A review of the most recent research conducted since 2014 demonstrates that effects of weight loss on asthma severity in adults with obesity and asthma has not been the focus of majority of the studies. Apart from our study published in 2015, very few studies used airway hyperresponsiveness as the primary or secondary outcome measure. The literature reveals that significant weight loss does, however, lead to improvement in asthma severity and control in adults with obesity and asthma.

SUMMARY

The current literature suggests that improvement in lung function requires moderate to significant (5-10%) weight loss in adults with obesity and asthma. However, with a few exceptions, the majority of these studies were small and used variable and questionable asthma severity outcome measures. There is an urgent need for standardization of diagnosis of asthma, study inclusion criteria, and outcome measures to assess asthma severity in research setting. Long-term effects of weight loss interventions on asthma severity and control, in adults with obesity and asthma, also remain unanswered.

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.

Central Role of IL-23 and IL-17 Producing Eosinophils as Immunomodulatory Effector Cells in Acute Pulmonary Aspergillosis and Allergic Asthma

Aspergillus fumigatus causes invasive pulmonary disease in immunocompromised hosts and allergic asthma in atopic individuals. We studied the contribution of lung eosinophils to these fungal diseases. By in vivo intracellular cytokine staining and confocal microscopy, we observed that eosinophils act as local sources of IL-23 and IL-17. Remarkably, mice lacking eosinophils had a >95% reduction in the percentage of lung IL-23p19⁺ cells as well as markedly reduced IL-23 heterodimer in lung lavage fluid. Eosinophils killed A. fumigatus conidia in vivo. Eosinopenic mice had higher mortality rates, decreased recruitment of inflammatory monocytes, and decreased expansion of lung macrophages after challenge with conidia. All of these functions underscore a potential protective role for eosinophils in acute aspergillosis. Given the postulated role for IL-17 in asthma pathogenesis, we assessed whether eosinophils could act as sources of IL-23 and IL-17 in models where mice were sensitized to either A. fumigatus antigens or ovalbumin (OVA). We found IL-23p19⁺ IL-17AF⁺ eosinophils in both allergic models. Moreover, close to 95% of IL-23p19⁺ cells and >90% of IL-17AF⁺ cells were identified as eosinophils. These data establish a new paradigm in acute and allergic aspergillosis whereby eosinophils act not only as effector cells but also as immunomodulatory cells driving the IL-23/IL-17 axis and contributing to inflammatory cell recruitment.

The opportunistic fungus, Aspergillus fumigatus, causes a spectrum of diseases ranging from invasive aspergillosis in the severely immunosuppressed to allergic asthma in atopic individuals. Here we explored the contribution of eosinophils, a type of white blood cell, to host defenses and pathogenesis in murine models of invasive pulmonary aspergillosis and asthma. We found eosinophils co-produce the cytokines IL-23 and IL-17 in both aspergillosis models as well as a model of OVA-induced asthma. Eosinophils killed the conidia (spores) of A. fumigatus in vivo and mice that lacked eosinophils were more susceptible to invasive aspergillosis. These observations suggest eosinophils play a more prominent role in defenses against invasive pulmonary aspergillosis than heretofore appreciated and identify eosinophil-derived IL-23 and IL-17 as potential therapeutic targets in allergic asthma.

Burden of systemic glucocorticoid-related complications in severe asthma

OBJECTIVES

Although systemic glucocorticoids (SGCs) are efficacious, their chronic use is associated with a range of complications. Yet limited data are available about the risks following chronic use in patients with severe asthma, who are at risk of long-term SGC-related complications. This study was carried out to investigate the risks of developing SGC-related complications, and to quantify the associated healthcare resource utilization and costs for patients with severe asthma in the United States.

METHODS

This was a longitudinal, open-cohort, observational study. Medicaid claims data (1997-2013) for patients ≥12 years old with ≥2 asthma diagnoses were used. A total of 26,987 SGC non-users were identified for inclusion in the study, alongside 3628 SGC users with ≥6 months' continuous SGC use.

RESULTS

Multivariate generalized estimating equation models were used to estimate the adjusted risk of developing SGC-related complications, and to quantify the associated healthcare resource utilization and costs. This analysis compared SGC users with SGC non-users, and found that SGC users had an increased likelihood of developing complications. A significant dose-response relationship was demonstrated between chronic SGC use and risk of developing any complications (odds ratios for low, medium, and high SGC exposure were 2.03 [p = .0511], 2.85 [p < .0001], and 3.64 [p < .0001], respectively, vs. SGC non-users). The increased likelihood of SGC-related complications translated into estimated annual healthcare costs for SGC users of $2712 to $8560 above those of SGC non-users. A key limitation of this study is the disparity in age between the SGC users and the SGC non-users; however, age was included as a confounding factor in the analysis.

CONCLUSIONS

These findings confirm the risk associated with chronic use of SGCs, irrespective of dose level, and highlight the need for new SGC-sparing treatment strategies for patients with severe asthma.

Measurement of utility in asthma: evidence indicating that generic instruments may miss clinically important changes

BACKGROUND

Accurate assessment of preference-based health-related quality of life is important in determining the value of asthma interventions.

OBJECTIVE

To examine the sensitivity and responsiveness of the EQ-5D and the AQL-5D to differences in asthma control measured by the Asthma Control Questionnaire (ACQ-5).

METHODS

The Observational Study of Asthma Control and Outcomes was a prospective survey of persistent asthma patients ≥12 years old in Kaiser Colorado. Patients received a survey three times in 1 year, including the ACQ-5, AQL-5D and EQ-5D-3L (including VAS). Censored Least Absolute Deviations (CLAD) and logistic regression were used, controlling for sociodemographics and smoking.

RESULTS

There were 6666 completed surveys (1799 individuals completed all three survey waves). After controlling for covariates, each one-point increase in ACQ-5 was associated with a decrease of 0.066, 0.058, 0.074 and 6.12 in EQ-5D(US), EQ-5D(UK), AQL-5D and VAS scores. Uncontrolled asthma (ACQ-5 > 1.5) was associated with a decrease of 0.15, 0.17, 0.11 and 10, respectively (vs. ACQ ≤ 1.5). AQL-5D scores were statistically significantly different across categories of ACQ-5 scores of 0.5 (the minimum clinically important difference [MCID]), while EQ-5D scores were not significant across most categories. The AQL-5D appeared more robust to changes in control over time (responsiveness) compared to EQ-5D-3L.

CONCLUSION

The AQL-5D appears more responsive to changes in asthma control over time and more sensitive to detecting differences corresponding to the ACQ-5 MCID than the EQ-5D-3L. Using the EQ-5D-3L without an asthma-specific measure such as the AQL-5D may miss clinically important changes in asthma control.

Curcumin ameliorates asthmatic airway inflammation by activating nuclear factor-E2-related factor 2/haem oxygenase (HO)-1 signalling pathway

Previous studies have shown that curcumin alleviates asthma in vivo. However, the relationship between curcumin and the nuclear factor-E2-related factor 2 (Nrf2)/haem oxygenase (HO)-1 pathway in asthma treatment remains unknown. The aim of the present study was to investigate the mechanisms of curcumin involved in the amelioration of airway inflammation in a mouse asthma model. Curcumin was administrated to asthmatic mice, and bronchoalveolar lavage fluid was collected. Inflammatory cell infiltration was measured by Giemsa staining. Immunoglobulin E production in bronchoalveolar lavage fluid was measured by enzyme-linked immunosorbent assay. Histological analyses were evaluated with haematoxylin-eosin and periodic acid-Schiff staining. Airway hyperresponsiveness was examined by whole-body plethysmography. Nuclear factor-E2-related factor 2, HO-1, nuclear factor-κB and inhibitory κB/p-inhibitory κB levels in lung tissues were detected by western blot, and Nrf2 activity was measured by electrophoretic mobility shift assay. Tumour necrosis factor-α, interleukin (IL)-1β, and IL-6 levels in the small interfering RNA-transfected cells were detected by enzyme-linked immunosorbent assay. Curcumin treatment significantly reduced immunoglobulin E production, attenuated inflammatory cell accumulation and goblet cell hyperplasia, and ameliorated mucus secretion and airway hyperresponsiveness. Nuclear factor-E2-related factor 2 and HO-1 levels in lung tissues were significantly increased. Meanwhile, Nrf2 activity was enhanced. Nuclear factor-κB and p-inhibitory κB levels were elevated in the lung tissue of ovalbumin-challenged mice. Both were restored to normal levels after curcumin treatment. Haem oxygenase-1 and nuclear Nrf2 levels were enhanced in dose- and time-dependent manners in curcumin-treated RAW264.7 cells. Curcumin blocked lipopolysaccharide-upregulated expression of tumour necrosis factor-α, IL-1β, and IL-6. After the cells were transfected with HO-1 or Nrf2 small interfering RNA, lipopolysaccharide-induced pro-inflammation cytokine expression was significantly restored. In summary, curcumin might alleviate airway inflammation in asthma through the Nrf2/HO-1 pathway, potentially making it an effective drug in asthma treatment.

Acute and chronic systemic corticosteroid-related complications in patients with severe asthma

BACKGROUND

Many patients with severe asthma require maintenance treatment with systemic corticosteroids (SCSs) to control daily symptoms and prevent serious acute exacerbations, but chronic SCS use is associated with complications.

OBJECTIVE

We sought to evaluate the risk of SCS-related complications by SCS exposure and quantify the associated health care costs and resource use in patients with severe asthma.

METHODS

We performed a longitudinal, open-cohort, observational study using health insurance claims data (1997-2013: Medicaid) from Florida, Iowa, Kansas, Missouri, Mississippi, and New Jersey. Eligible patients were 12 years old or older with 2 or more asthma diagnoses and had more than 6 months of continuous SCS use. An open-cohort approach was used to classify patients' follow-up into low, medium, and high SCS exposure (≤ 6, >6-12, and >12 mg/d, respectively). Multivariate generalized estimating equation models were used to estimate the adjusted risk of SCS-related complications for patients with medium and high exposure compared with patients with low exposure and quantify the resulting health care resource use and costs.

RESULTS

The study included 3628 patients (mean age, 57.6 years; 68% female). Patients with medium and high SCS exposure had significantly higher risks of SCS-related complications, including infections and cardiovascular, metabolic, psychiatric, ocular, gastrointestinal, and bone-related complications (odds ratio, 1.23-2.12 by complication; P < .05 for all but one) versus those with low (reference group) SCS exposure. Medium and high SCS exposure were also associated with significantly more emergency department visits (incidence rate ratios, 1.31 [P = .0004] and 1.78 [P < .0001]) and inpatient visits (incidence rate ratios, 1.25 [P < .0001] and 1.59 [P < .0001]) versus low SCS exposure.

CONCLUSIONS

A significant dose-response relationship was demonstrated between chronic SCS use and risk of SCS-related complications in patients with severe asthma. Effective SCS-sparing strategies might reduce the burden associated with SCS-related complications in patients with severe asthma.

A long-acting β2-adrenergic agonist increases the expression of muscarine cholinergic subtype‑3 receptors by activating the β2-adrenoceptor cyclic adenosine monophosphate signaling pathway in airway smooth muscle cells

The persistent administration of β₂-adrenergic (β₂AR) agonists has been demonstrated to increase the risk of severe asthma, partly due to the induction of tolerance to bronchoprotection via undefined mechanisms. The present study investigated the potential effect of the long-acting β₂-adrenergic agonist, formoterol, on the expression of muscarinic M3 receptor (M₃R) in rat airway smooth muscle cells (ASMCs). Primary rat ASMCs were isolated and characterized following immunostaining with anti-α-smooth muscle actin antibodies. The protein expression levels of M₃R and phospholipase C-β₁ (PLCβ₁) were characterized by western blot analysis and the production of inositol 1,4,5-trisphosphate (IP₃) was determined using an enzyme-linked immunosorbent assay. Formoterol increased the protein expression of M₃R in rat ASMCs in a time- and dose-dependent manner, which was significantly inhibited by the β₂AR antagonist, ICI118,551 and the cyclic adenosine monophosphate (cAMP) inhibitor, SQ22,536. The increased protein expression of M₃R was positively correlated with increased production of PLCβ₁ and IP₃. Furthermore, treatment with the glucocorticoid, budesonide, and the PLC inhibitor, U73,122, significantly suppressed the formoterol-induced upregulated protein expression levels of M₃R and PLCβ₁ and production of IP₃. The present study demonstrated that formoterol mediated the upregulation of M₃R in the rat ASMCs by activating the β₂AR-cAMP signaling pathway, resulting in increased expression levels of PLCβ₁ and IP₃, which are key to inducing bronchoprotection tolerance. Administration of glucocorticoids or a PLC antagonist prevented formoterol-induced bronchoprotection tolerance by suppressing the protein expression of M₃R.

Comparative effectiveness of budesonide-formoterol combination and fluticasone-salmeterol combination for asthma management: a United States retrospective database analysis

BACKGROUND

Comparative effectiveness of the budesonide-formoterol fumarate dihydrate combination (BFC) and the fluticasone propionate-salmeterol combination (FSC) therapy on asthma exacerbation has not been assessed in real-world settings in the United States.

OBJECTIVE

To compare exacerbation rates and health care utilization for patients with asthma who initiate BFC versus FSC therapy.

METHODS

This retrospective cohort comparative effectiveness study queried medical and pharmacy data for patients with asthma from a large managed care data repository that covers major US population centers. The patients were 12 to 64 years old, with ≥12 months of pre- and postindex enrollment and ≥1 pharmacy claim(s) for BFC or FSC initiated during June 1, 2007, and September 30, 2010; the first prescription fill date was defined as the index date. Patients with other respiratory diseases and/or cancer were excluded. Exacerbation was defined as asthma-related hospitalization, emergency department visit, and/or oral corticosteroid prescription fill. Cohorts were matched by using propensity scores.

RESULTS

A total of 3043 patients per cohort were matched and balanced. During the 12 months following the initiation the BFC cohort had lower adjusted exacerbations per person year versus the FSC cohort (0.85 vs 0.93; RR 0.92, 95% CI [0.85-0.99]), lower oral corticosteroid fill rates, and fewer asthma-related emergency department visits but comparable asthma-related hospitalization.

CONCLUSIONS

Asthma exacerbation was lower for BFC versus FSC initiators due to lower rates of oral corticosteroid use and asthma-related emergency department visits, which indicate better treatment effectiveness of those patients initiated with BFC compared with FSC.

Local and systemic tolerability of a 2'O-methoxyethyl antisense oligonucleotide targeting interleukin-4 receptor-α delivery by inhalation in mouse and monkey

Antisense oligonucleotides (ASOs) bind and facilitate degradation of RNA and inhibit protein expression in pathways not easily targeted with small molecules or antibodies. Interleukin (IL)-4 and IL-13 potentiate signaling through the shared IL-4 receptor-α (IL-4Rα) subunit of their receptors. ASO targeting of IL-4Rα mRNA in a mouse model of asthma led to attenuation of airway hyperactivity, demonstrating potential benefit in asthma patients. This study focused on tolerability of inhaled IL-4Rα-targeting ASOs. Toxicity studies were performed with mouse- (ISIS 23189) and human-specific (ISIS 369645) sequences administered by inhalation. Four week (monkey) or 13 week (mouse) repeat doses at levels of up to 15 mg/kg/exposure (exp) and 50 mg/kg/exp, respectively, demonstrated dose-dependent effects limited to increases in macrophage size and number in lung and tracheobronchial lymph nodes. The changes were largely non-specific, reflecting adaptive responses that occur during active exposure and deposition of ASO and other material in the lung. Reversibility was observed at a rate consistent with the kinetics of tissue clearance of ASO. Systemic bioavailability was minimal, and no systemic toxicity was observed at exposure levels appreciably above pharmacological doses and doses proposed for clinical trials.

Effect of physical training on airway inflammation in bronchial asthma: a systematic review

Background

The majority of the global population cannot afford existing asthma pharmacotherapy. Physical training as an airway anti-inflammatory therapy for asthma could potentially be a non-invasive, easily available, affordable, and healthy treatment modality. However, effects of physical training on airway inflammation in asthma are currently inconclusive. The main objective of this review is to summarize the effects of physical training on airway inflammation in asthmatics.

Methods

A peer reviewed search was applied to Medline, Embase, Web of Science, Cochrane, and DARE databases. We included all observational epidemiological research studies and RCTs. Studies evaluating at least one marker of airway inflammation in asthmatics after a period of physical training were selected. Data extraction was performed in a blinded fashion. We decided a priori to avoid pooling of the data in anticipation of heterogeneity of the studies, specifically heterogeneity of airway inflammatory markers studied as outcome measures.

Results

From the initial 2635 studies; 23 studies (16 RCTs and 7 prospective cohort studies) were included. Study sizes were generally small (median sample size = 30). There was a reduction in C-reactive protein, malondialdehyde, nitric oxide, sputum cell counts and IgE in asthmatics with physical training. Mixed results were observed after training for fractional excretion of nitric oxide and bronchial hyperresponsiveness. The data was not pooled owing to significant heterogeneity between studies, and a funnel plot tests for publication bias were not performed because there were less than 10 studies for almost all outcome measures. Physical training intervention type, duration, intensity, frequency, primary outcome measures, methods of assessing outcome measures, and study designs were heterogeneous.

Conclusion

Due to reporting issues, lack of information and heterogeneity there was no definite conclusion; however, some findings suggest physical training may reduce airway inflammation in asthmatics.

Refractory asthma treatment is complicated by tracheobronchomalacia: case reports and review of the literature

Tracheobronchomalacia (TBM) is defined as the condition where the airway lumen narrows more than 50 percent. The acquired TBM usually occurs in adults; however, the prevalence of TBM in asthma is unknown. We report two cases of severe asthma in elderly patients that could not be controlled with higher medication use. Case 1 was a 70-year-old woman with sever persistent asthma for 10 years, presented with uncontrolled symptoms for 4 months. A CT of the chest showed collapse of the trachea at the posterior wall. Case 2 involved a 72-year-old woman with partly controlled asthma presenting with uncontrolled symptoms for 3 months. A CT of the chest showed normal distal tracheal anteroposterior diameter. However, bronchoscopy showed bronchomalacia at the right and left bronchus of the lower lungs. Patients who have severe asthma, despite adequate treatment with medication, should be further investigated to exclude other diseases that have clinical features similar to asthma such as tracheobronchomalacia, particularly in the elderly.

Inflammatory marker sTREM-1 reflects the clinical stage and respiratory tract obstruction in allergic asthma bronchiale patients and correlates with number of neutrophils

The knowledge that asthma is an inflammatory disorder has prompted us to investigate the plasma levels of a new inflammatory marker sTREM-1 that is released from the surfaces of activated neutrophils and monocytes. The plasma levels of sTREM-1 were analysed by a sandwich ELISA test in the cohort of 76 patients with allergic asthma bronchiale and 39 healthy controls. Our results revealed more than 3.5 times higher levels of sTREM-1 in AB patients (92.3 pg/mL ± 125.6) compared with healthy subjects (25.7 pg/mL ± 9.2; P = 0.0001). Higher levels of sTREM-1 were found also in patients with exacerbated AB (170.5 pg/mL ± 78.2) compared with nonexacerbated AB patients (59.1 ± 78.2; P < 0.0001), patients with respiratory tract obstruction (176.4 pg/mL ± 177.8), than those without obstruction (51.99 pg/mL ± 64.0; P < 0.0001) and patients with anti-IgE therapy (P < 0.0001). Levels of sTREM-1 correlated with number of leucocytes (P = 0.002), and absolute number of neutrophils (P = 0.001). Elevated plasma levels of sTREM-1 reflect the severity, state of exacerbation, presence of respiratory tract obstruction in AB patients and together with increased number of neutrophils point to the role of neutrophils in inflammation accompanying AB.