Severe asthma-A population study perspective

PI3K pathway activation in severe asthma is linked to steroid insensitivity and adverse outcomes

Background

Patients with severe asthma may demonstrate reduced sensitivity to steroid treatment. However, the implications of this reduced responsiveness for clinical outcomes and the underlying mechanisms remain unclear.

Objective

The aim of this study was to investigate whether steroid sensitivity in patients with asthma is related to severity and clinical outcomes and to elucidate the role of inflammatory pathways in reducing steroid sensitivity.

Methods

This observational study of 169 asthma patients, with 161 followed for 1 year, involved isolation of peripheral blood mononuclear cells. These cells were treated with dexamethasone, and the mRNA expression of FKBP5, which is a marker of steroid sensitivity, was measured. To explore the mechanism underlying the reduced steroid sensitivity, cells were exposed to PI3K and MAPK inhibitors in combination with dexamethasone.

Results

A total of 53 patients diagnosed with severe asthma exhibited markedly diminished sensitivity to steroids compared with those with nonsevere asthma. Reduced steroid sensitivity has emerged as a critical risk factor for failure to experience clinical remission and exacerbation. This relationship between reduced steroid sensitivity and disease severity and adverse outcomes was confirmed at the 1-year follow-up. Mechanistic investigations revealed that the degree of recovery from steroid sensitivity after PI3Kδ/γ inhibitor treatment was significantly greater in patients with severe asthma than in those with nonsevere asthma, a finding confirmed at the 1-year follow-up.

Conclusions

Patients with severe asthma demonstrate reduced steroid sensitivity, which results in unfavorable clinical outcomes. Conversely, inhibition of the PI3K pathway significantly improves steroid sensitivity.

Airway epithelial cells as drivers of severe asthma pathogenesis

Our understanding of the airway epithelium's role in driving asthma pathogenesis has evolved over time. From being regarded primarily as a physical barrier that could be damaged via inflammation, the epithelium is now known to actively contribute to asthma development through interactions with the immune system. The airway epithelium contains multiple cell types with specialized functions spanning barrier action, mucociliary clearance, immune cell recruitment, and maintenance of tissue homeostasis. Environmental insults may cause direct or indirect injury to the epithelium leading to impaired barrier function, epithelial remodelling, and increased release of inflammatory mediators. In severe asthma, the epithelial barrier repair process is inhibited and the response to insults is exaggerated, driving downstream inflammation. Genetic and epigenetic mechanisms also maintain dysregulation of the epithelial barrier, adding to disease chronicity. Here, we review the role of the airway epithelium in severe asthma and how targeting the epithelium can contribute to asthma treatment.

Aspergillus-mediated allergic airway inflammation is triggered by dendritic cell recognition of a defined spore morphotype

BACKGROUND

Exposure to fungi, especially Aspergillus fumigatus, can elicit potent allergic inflammation that triggers and worsens asthmatic disease. Dendritic cells (DCs) initiate allergic inflammatory responses to allergic stimuli. However, it is unclear if Af spores during isotropic growth (early spore swelling) can activate DCs to initiate allergic responses or if germination is required. This lack of basic understanding of how Af causes disease is a barrier to developing new treatments.

OBJECTIVE

We sought to show that a precise Af morphotype stage during spore swelling can trigger DCs to mediate allergic inflammatory responses and ascertain if antifungal therapeutics can be effective at suppressing this process.

METHODS

We used an Af strain deficient in pyrimidine biosynthesis (ΔpyrG) to generate populations of Af spores arrested at different stages of isotropic growth (swelling) via temporal removal of uracil and uridine from growth media. These arrested spore stages were cultured with bone marrow-derived DCs (BMDCs), and their activation was measured via flow cytometry and ELISA to examine which growth stage was able to activate BMDCs. These BMDCs were then adoptively transferred into the airways to assess if they were able to mediate allergic inflammation in naïve recipient mice. Allergic airway inflammation in vivo was determined via flow cytometry, ELISA, and real-time quantitative PCR. This system was also used to determine if antifungal drug (itraconazole) treatment could alter early stages of spore swelling and therefore BMDC activation and in vivo allergic inflammation upon adoptive transfer.

RESULTS

We found that Af isotropic growth is essential to trigger BMDC activation and mediate allergic airway inflammation. Furthermore, using time-arrested Af stages, we found that at least 3 hours in growth media enabled spores to swell sufficiently to activate BMDCs to elicit allergic airway inflammation in vivo. Incubation of germinating Af with itraconazole reduced spore swelling and partially reduced their ability to activate BMDCs to elicit in vivo allergic airway inflammation.

CONCLUSION

Our results have pinpointed the precise stage of Af development when germinating spores are able to activate DCs to mediate downstream allergic airway inflammation. Furthermore, we have identified that antifungal therapeutics partially reduced the potential of Af spores to stimulate allergic responses, highlighting a potential mechanism by which antifungal treatment might help prevent the development of fungal allergy.

Characteristics of patients with severe asthma reported to be eligible or non-eligible for biologic therapy in Poland: Results from the international observational study RECOGNISE

PURPOSE

To analyze characteristics of real-world patients with severe asthma in Poland and identify factors determining clinicians' opinion on the eligibility for biologics.

METHODS

In this retrospective, multi-national, single-visit study (NCT03629782), investigators were asked whether the patient might benefit from a referral for further clinical assessment and potentially biologic therapy. Asthma exacerbations and healthcare resource utilization (HCRU) in the last 12 months were documented by the investigators. Patient-reported outcomes included St George's Respiratory Questionnaire (SGRQ) and Asthma Control Questionnaire (ACQ-6).

RESULTS

Of 1025 patients, 146 were enrolled in Poland. Investigators considered 77.4 ​% of patients eligible for biologics and 22.6 ​% non-eligible. Patients considered eligible were diagnosed at younger age than non-eligible (median 39 vs 45 years; p ​= ​0.0113) and more frequently had a history of atopy (46 ​% vs 21.2 ​%; p ​= ​0.0106). Eligible patients had a higher frequency (93.8 ​% vs 66.7 ​%, p ​< ​0.0001) and number of exacerbations (median 2 vs 1, p ​= ​0.0003). Among eligible patients, 81.4 ​% and among non-eligible, 66.7 ​% had not well-controlled asthma; long-term oral corticosteroids were used by 46.0 ​% and 51.5 ​%, respectively. Short-term corticosteroid use was more frequent in biologics-eligible than in non-eligible patients (82.3 ​% vs 48.5 ​%, p ​< ​0.0001). Patients eligible for biologics had a higher median SGRQ total score (64.7 vs 48.4; p ​= ​0.0075) and HRCU (63.7 ​% vs 9.1 ​%; p ​< ​0.0001).

CONCLUSIONS

In Poland, 3 in 4 patients with severe asthma are recognized by clinicians as potential candidates for biologics. However, eligibility is not associated with long-term oral corticosteroid use, highlighting the need to better inform the physicians about the benefits of biologic therapy.

T2-low severe asthma clinical spectrum and impact: The Greek PHOLLOW cross-sectional study

BACKGROUND

Data on type 2 (T2)-low severe asthma (SA) frequency is scarce, resulting in an undefined unmet therapeutic need in this patient population. Our objective was to assess the frequency and characterize the profile and burden of T2-low SA in Greece.

METHODS

PHOLLOW was a cross-sectional study of adult SA patients. Based on a novel proposed classification system, patients were classified as T2-low if blood eosinophil count (BEC; cells/μL) was <150, fractional exhaled nitric oxide (FeNO) < 25 ppb and any allergy status or BEC < 150/FeNO < 50 ppb/no allergy or BEC < 300/FeNO < 25 ppb/no allergy. For patients receiving biologics and/or oral corticosteroids, only those with BEC < 150/FeNO < 25 ppb/no allergy/no response to therapy were classified as T2-low. Secondary outcome measures were: Asthma Control Test (ACTTM), Mini-Asthma Quality of Life Questionnaire (Mini-AQLQ), hospital anxiety and depression scale (HADS), and Work Productivity and Activity Impairment:Respiratory Symptoms (WPAI:RS) questionnaire.

RESULTS

From 22-Mar-2022 to 15-Mar-2023, 602 eligible SA patients were enrolled. The frequency of T2-low asthma was 20.1%. Of those, 71.1% had experienced ≥1 clinically significant exacerbations in the past year, 62.8% had ACT score <20 (uncontrolled asthma), and 22.3% were biologic-treated. Mini-AQLQ score was <6 (impairment) in 79.5% of patients, HADS-total score was ≥15 (clinically significant emotional distress) in 43.8%, while median percent activity impairment and work productivity loss were 30.0 for both domains. Clinical and patient-reported outcomes were worse among patients with ACT-defined uncontrolled asthma.

CONCLUSIONS

One-fifth of SA patients present with a T2-low endotype. These patients frequently have uncontrolled disease and experience impairments in their quality of life, emotions and work ability.

Class III Obesity as a Risk Factor for Persistent Asthma

Background: The burden of asthma remains steady with no decline observed in the past few decades. Obesity prevalence has been steadily increasing with a rate of 41.9% in the United States between 2017-2020. Obesity is an inflammatory chronic condition that may partially contribute to the burden and severity of asthma. This study aimed to examine whether the association between obesity and asthma varies with the categories of obesity (class I, II, and III) and persistent asthma (mild, moderate, and severe asthma). We hypothesized that subjects with elevated body mass index (BMI) are more likely to be diagnosed with persistent asthma than subjects without obesity with asthma. Methods: As a retrospective and cross-sectional study, this study used a total of 1,977 records of subjects with asthma (age ≥ 19 y) hospitalized in Nevada between 2016-2021. BMI and persistent asthma were evaluated as the main exposure and outcome of interest. Logistic regression was used to estimate the magnitude of the association between obesity and persistent asthma. Results: Among the selected subject records, subjects with obesity were more likely to be diagnosed with persistent asthma compared to subjects without obesity (odds ratio 1.50 [CI 1.10-2.05]). Subgroup analyses revealed that subjects with class III obesity (BMI ≥ 40) were more likely than subjects without obesity to be diagnosed with mild persistent asthma (odds ratio 2.21 [CI 1.18-4.16]) and severe persistent asthma (odds ratio 1.74 [CI 1.12-2.70]). Conclusions: Obesity was identified as a risk factor for persistent asthma, particularly class III obesity. This in turn increases the potential for greater health care utilization and economic burden. Public health and clinical interventions are necessary among those with comorbid asthma and obesity.

Factors associated with uncontrolled severe asthma in the biologic era

BACKGROUND

Despite the development of biologics for severe asthma, individuals with uncontrolled status persist, posing a significant social problem. This multicenter prospective study aimed to identify factors associated with the uncontrolled status of patients with severe asthma in the biologic era assessed using the Asthma Control Questionnaire (ACQ).

METHODS

Subjects with severe asthma diagnosed by respiratory specialists were enrolled from 11 hospitals. Clinical data and questionnaires were collected. We compared controlled (ACQ-5 <1.5) with uncontrolled severe asthma (ACQ-5 ≥1.5) and assessed factors linked to uncontrolled severe asthma using logistic regression analysis.

RESULTS

One hundred fifty-four patients were analyzed (median age, 66 years; 62.3 % female; 52.6 % administered biologics). Among them, 56 patients (36.4 %) had uncontrolled severe asthma (ACQ-5 ≥1.5). The uncontrolled group had more frequent exacerbations (≥2 times in the previous year) and elevated blood neutrophil counts compared with the controlled group. Factors associated with uncontrolled status were analyzed in the overall population, with patients stratified into two groups: those receiving biologics and those not receiving biologics. Multivariate analysis revealed that frequent exacerbations and elevated blood neutrophil counts were associated with uncontrolled status in the overall population and in patients without biologics, whereas elevated blood neutrophil counts were significantly associated with uncontrolled status in patients receiving biologics.

CONCLUSION

Elevated blood neutrophil counts and frequent exacerbations were independently associated with uncontrolled severe asthma. Specifically, elevated blood neutrophil counts were a significant factor related to uncontrolled status irrespective of biologics, suggesting their potential utility as a biomarker in the biologic era.

Fungal disease incidence and prevalence in Iraq - Preliminary estimates

BACKGROUND

The surveillance of serious and superficial skin fungal infections in Iraq has not been conducted. Limited information exists on their incidence and prevalence.

OBJECTIVES

This study aimed to analyze, compute and estimate the prevalence and burden of fungal infections, as no previous data is available and no studies has been attempted in Iraq.

METHODS

In the present study the data were collected and reviewed from published data on epidemiology of fungal infections nationally, internationally, from unpublished postgraduate master and PhD theses, hospital records and private clinic records. External sources of data from other countries were used for diseases which lacked sufficient local data.

RESULTS

We estimated 985,628 annual serious infections comprising of 2.26 % of the total population. When including superficial fungal infections group of the skin, this rises to 2,075,113 infections at 4.76 % of the total population. The most common serious and skin infections were recurrent Candida vaginitis, fungal rhinosinusitis and tinea capitis comprising 61.5 %, 21.8 %, and 22.4 % of all infections although the total incidence of superficial fungal infections was also high at 1,071,485. Respiratory fungal disease is also common comprising 14.0 % of infections. We predicted the following annual burden per 100,000; oral candidiasis at 247.9, esophageal candidiasis at 6.04, candidemia at 5.0, Candida peritonitis at 0.75, recurrent Candida vaginitis at 5461, allergic bronchopulmonary aspergillosis at 35, severe asthma with fungal sensitisation at 46, invasive aspergillosis at 7.9, chronic pulmonary aspergillosis at 11.7, chronic fungal rhinosinusitis at 496, mucormycosis at 0.99, fungal keratitis at 14.0, and total dermatophytosis at 1631, the most severe being tinea capitis at 366. Many of these estimates were made with data sourced from other nations, so additional data from Iraq is required to validate or modify these estimates.

CONCLUSION

Recurrent Candida vaginitis, fungal rhinosinusitis, and tinea capitis are considered to be the most frequent fungal diseases present in Iraq.

Four-month real-life response to Tezepelumab in patients with multi-failure to other biologics

To evaluate the response to Tezepelumab in real clinical practice, we performed an analysis of the clinical, functional, and inflammatory characteristics of 13 patients with severe asthma after completing four doses of Tezepelumab was performed. When comparing clinical parameters such as asthma control test (ACT), FENO value, exacerbations in the last 4 months, blood eosinophils and FEV1%, before receiving Tezepelumab and after four doses of Tezepelumab, statistically significant differences were found in ACT levels (p=0.0072), exacerbations (p=0.018) and FEV1% (p=0.012) before and after four doses of Tezepelumab. No statistically significant differences were found in blood eosinophils or FeNO levels, however, a mean reduction of 102.5±231 cells/mm3 and 14.67±30 ppb, respectively, was observed. Patients with a high T2 profile had significantly higher baseline FeNO (p<0.05), but no significant improvement in lung function or asthma control was observed in this group. Patients with Aspirin-exacerbated respiratory disease (AERD) were evaluated separately. There was no difference in ACT, FeNO, or lung function changes after tezepelumab use compared to patients without AERD (all p>0.05). We demonstrated, in a multicenter study, the clinical improvement associated with tezepelumab treatment in severe uncontrolled asthma, independent of inflammatory biomarkers, eosinophilic profile, or previous biological failure.

Disease Burden and Access to Biologic Therapy in Patients with Severe Asthma, 2017-2022: An Analysis of the International Severe Asthma Registry

Introduction

Patients with severe asthma may be prescribed biologic therapies to improve disease control. The EVEREST study aimed to characterize the global disease burden of patients with severe asthma without access to biologics and those who have access but do not receive biologics, as well as the remaining unmet need despite use of these therapies.

Methods

This was a historical cohort study of patients with severe asthma (aged ≥18 years) in the International Severe Asthma Registry receiving Global Initiative for Asthma (GINA) 2018 step 5 treatment, or with uncontrolled disease at GINA step 4. Prospective data on patient clinical characteristics, healthcare resource utilization, and medication use over a 12-month period between December 2017 and May 2022 were assessed for the following five groups: biologics accessible (omalizumab, mepolizumab, reslizumab, benralizumab, or dupilumab); biologics inaccessible; biologics accessible but not received; biologics accessible and received; and biologic recipients whose asthma remained suboptimally controlled.

Results

Overall, 9587 patients from 21 countries were included. Among patients in the biologics accessible (n=5073), biologics inaccessible (n=3041), and biologics accessible but not received (n=382) groups, 41.4%, 18.7%, and 49.6% experienced at least two exacerbations, 11.5%, 10.5%, and 6.2% required at least one hospitalization, 47.9%, 54.6%, and 71.2% had uncontrolled asthma, and 23.9%, 8.6%, and 11.0% received long-term oral corticosteroids (LTOCS), respectively. Following biologic therapy, among patients who received biologics overall (n=2666) and among those whose asthma remained suboptimally controlled (n=1780), 19.1% and 23.0% experienced at least two exacerbations, 2.7% and 2.9% required at least one hospitalization, and 16.7% and 22.0% received LTOCS, respectively.

Conclusion

There is a substantial disease burden in both patients without access to biologics and those with access who do not receive these therapies, although specific outcomes may vary between these groups. There also remains a high unmet need among biologic recipients, many of whom have a suboptimal response to treatment.

SIRPα engagement regulates ILC2 effector function and alleviates airway hyperreactivity via modulating energy metabolism

Group-2 innate lymphoid cells (ILC2) are part of a growing family of innate lymphocytes known for their crucial role in both the development and exacerbation of allergic asthma. The activation and function of ILC2s are regulated by various activating and inhibitory molecules, with their balance determining the severity of allergic responses. In this study, we aim to elucidate the critical role of the suppressor molecule signal regulatory protein alpha (SIRPα), which interacts with CD47, in controlling ILC2-mediated airway hyperreactivity (AHR). Our data indicate that activated ILC2s upregulate the expression of SIRPα, and the interaction between SIRPα and CD47 effectively suppresses both ILC2 proliferation and effector function. To evaluate the function of SIRPα in ILC2-mediated AHR, we combined multiple approaches including genetically modified mouse models and adoptive transfer experiments in murine models of allergen-induced AHR. Our findings suggest that the absence of SIRPα leads to the overactivation of ILC2s. Conversely, engagement of SIRPα with CD47 reduces ILC2 cytokine production and effectively regulates ILC2-dependent AHR. Furthermore, the SIRPα-CD47 axis modulates mitochondrial metabolism through the JAK/STAT and ERK/MAPK signaling pathways, thereby regulating NF-κB activity and the production of type 2 cytokines. Additionally, our studies have revealed that SIRPα is inducible and expressed on human ILC2s, and administration of human CD47-Fc effectively suppresses the effector function and cytokine production. Moreover, administering human CD47-Fc to humanized ILC2 mice effectively alleviates AHR and lung inflammation. These findings highlight the promising therapeutic potential of targeting the SIRPα-CD47 axis in the treatment of ILC2-dependent allergic asthma.

Health-related quality of life in severe hypersensitivity reactions: focus on severe allergic asthma and hymenoptera venom anaphylaxis-a cross-sectional study

Background

Growing evidence reveals the important role of clinical psychological factors in chronic-immune diseases. The aim of this study was to investigate Health-Related Quality of Life (HR-QoL), depression, anxiety, and alexithymia in patients with severe hypersensitivity reactions such as Severe Allergic Asthma (SAA) and Hymenoptera Venom Anaphylaxis (HVA).

Methods

The Short-Form Health Survey-36 (SF-36), the Beck Depression Inventory Questionnaire (BDI-II), the Hamilton Anxiety Rating Scale (HAM-A) and the Toronto Alexithymia Scale (TAS-20) were used to assess HR-QoL and clinical psychological features of patients with SAA and HVA.

Results

Overall, 78 patients were recruited. Patients with SAA (n = 35) reported lower scores for physical functioning [65 (58-75) vs. 90 (85-95); p = <0.001], role limitations due to physical health [25 (0-50) vs. 62 (50-75); p = 0.004], bodily pain [47.5 (41.1-61.3) vs. 55.5 (55-96); p = 0.001], general health [40 (30-60) vs. 70 (50-80); p = 0.0003] and social functioning [50 (37.5-62.5) vs. 62.5 (54.9-75); p = 0.007] while higher scores for depressive symptoms [14 (11-15.4) vs. (9.5 (6-15.4); p = 0.05)] compared to HVA patients (n = 43). All the dimensions of SF-36 were negatively correlated with anxiety (r from -0.26 to -0.66; p all < 0.01) and depressive symptoms (r from -0.44 to -0.73; p all < 0.001). Alexithymia was negatively correlated with vitality (r = -0.28; p = 0.02) and mental health (r = -027; p = 0.03). Additionally, patients with alexithymia (38% of participants) showed higher levels of depressive symptoms [9.5 (10-19) vs. 14 (6-13.9); p = 0.005] and anxiety levels [31 (27.9-35) vs. 24 (16-33.9); p = 0.02]; they also showed less vitality [40 (39.9-50) vs. 55 (50-60) p = 0.01], social functioning [50 (37.5-62.5) vs. 62.5 (50 vs. 75); p = 0.01] and mental health [48 (44-60) vs. 68 (56-76); p = 0.004].

Conclusion

Clinical psychological features due to severe hypersensitive reactions may contribute to the patient's perceived HR-QoL. Focused clinical psychological interventions should be promoted to improve the clinical management of such conditions.

Adjuvant-independent airway sensitization and infection mouse models leading to allergic asthma

Asthma is a chronic respiratory disease of global importance. Mouse models of allergic asthma have been instrumental in advancing research and novel therapeutic strategies for patients. The application of relevant allergens and physiological routes of exposure in such models has led to valuable insights into the complexities of asthma onset and development as well as key disease mechanisms. Furthermore, environmental microbial exposures and infections have been shown to play a fundamental part in asthma pathogenesis and alter disease outcome. In this review, we delve into physiological mouse models of allergic asthma and explore literature reports on most significant interplays between microbial infections and asthma development with relevance to human disease.

Population Pharmacokinetic Modeling and Exposure-Efficacy and Body Weight-Response Analyses for Tezepelumab in Patients With Severe, Uncontrolled Asthma

Tezepelumab is a human monoclonal antibody that blocks the activity of thymic stromal lymphopoietin. This analysis assessed the suitability of a fixed-dose regimen of tezepelumab 210 mg every 4 weeks (Q4W) in adults and adolescents with severe, uncontrolled asthma. A population pharmacokinetic model was developed using data from 1368 patients with asthma or healthy participants enrolled in 8 clinical studies (phases 1-3). Tezepelumab exposure-efficacy relationships were analyzed in the phase 3 NAVIGATOR study (NCT03347279), using asthma exacerbation rates over 52 weeks and changes in pre-bronchodilator forced expiratory volume in 1 s at week 52. Tezepelumab pharmacokinetics were well characterized by a 2-compartment linear disposition model with first-order absorption and elimination following subcutaneous and intravenous administration at 2.1-420 and 210-700 mg, respectively. There were no clinically relevant effects on tezepelumab pharmacokinetics from age (≥12 years), sex, race/ethnicity, renal or hepatic function, disease severity (inhaled corticosteroid dose level), concomitant asthma medication use, smoking history, or anti-drug antibodies. Body weight was the most influential covariate on tezepelumab exposure, but no meaningful differences in efficacy or safety were observed across body weight quartiles in patients with asthma who received tezepelumab 210 mg subcutaneously Q4W. There was no apparent relationship between tezepelumab exposure and efficacy at this dose regimen, suggesting that it is on the plateau of the exposure-response curve of tezepelumab. In conclusion, a fixed-dose regimen of tezepelumab 210 mg subcutaneously Q4W is appropriate for eligible adults and adolescents with severe, uncontrolled asthma.

Expert consensus on oral corticosteroids stewardship for the treatment of severe asthma in the Middle East and Africa

In the Middle East and Africa (MEA) region, overuse of oral corticosteroids (OCS) for asthma management, both as burst and maintenance therapy, poses a significant challenge. Gaps in knowledge regarding the need to taper OCS in patients with severe asthma and the use of OCS in comorbid conditions have been noted. OCS stewardship can help attain optimal and effective OCS tapering along with reducing OCS overuse and over-reliance. In this paper, we discuss current practices regarding the use of OCS in asthma, globally and in the MEA region. Expert recommendations for achieving OCS stewardship in the MEA region have also been presented. Regional experts recommend increasing awareness among patients about the consequences of OCS overuse, engaging community pharmacists, and educating primary healthcare professionals about the benefits of prompt appropriate referral. Innovative local referral tools like ReferID can be utilized to refer patients with asthma to specialist care. The experts also endorse a multidisciplinary team approach and accelerating access to newer medicines like biologics to implement OCS stewardship and optimize asthma care in the MEA region.

Impact of patient support programmes among patients with severe asthma treated with biological therapies: a systematic literature review and indirect treatment comparison

INTRODUCTION

Effective treatment of severe asthma requires patient adherence to inhaled and biological medications. Previous work has shown that patient support programmes (PSP) can improve adherence in patients with chronic diseases, but the impact of PSPs in patients with severe asthma treated with biologics has not been thoroughly investigated.

METHODS

We conducted a systematic literature review to understand the impact of PSPs on treatment adherence, asthma control and health-related quality of life (HRQoL) in patients with severe asthma. Embase, MEDLINE and EconLit databases were searched for studies published from 2003 (the year of the first biological approval for severe asthma) to June 2023 that described PSP participation among patients with severe asthma on biological treatment. Direct pooling of outcomes was not possible due to the heterogeneity across studies, so an indirect treatment comparison (ITC) was performed to determine the effect of PSP participation on treatment discontinuation. The ITC used patient-level data from patients treated with benralizumab either enrolled in a PSP (VOICE study, Connect 360 PSP) or not enrolled in a PSP (Benralizumab Patient Access Programme study) in the UK.

FINDINGS

25 records of 21 studies were selected. Six studies investigated the impact of PSPs on treatment adherence, asthma control or HRQoL. All six studies reported positive outcomes for patients enrolled in PSPs; the benefits of each PSP were closely linked to the services provided. The ITC showed that patients in the Connect 360 PSP group were less likely to discontinue treatment compared with the non-PSP group (OR 0.26, 95% CI 0.11 to 0.57, p<0.001).

CONCLUSIONS

PSPs contribute to positive clinical outcomes in patients with severe asthma on biological treatment. Future analyses will benefit from thorough descriptions of PSP services, and study designs that allow direct comparisons of patient outcomes with and without a PSP.

The burden of severe asthma in sub-Saharan Africa: Findings from the African Severe Asthma Project

Background

Severe asthma is associated with high morbidity, mortality, and health care utilization, but its burden in Africa is unknown.

Objective

We sought to determine the burden (prevalence, mortality, and activity and work impairment) of severe asthma in 3 countries in East Africa: Uganda, Kenya, and Ethiopia.

Methods

Using the American Thoracic Society/European Respiratory Society case definition of severe asthma, we analyzed for the prevalence of severe asthma (requiring Global Initiative for Asthma [GINA] steps 4-5 asthma medications for the previous year to achieve control) and severe refractory asthma (remains uncontrolled despite treatment with GINA steps 4-5 asthma medications) in a cohort of 1086 asthma patients who had been in care for 12 months and had received all GINA-recommended medications. Asthma control was assessed by the asthma control questionnaire (ACQ).

Results

Overall, the prevalence of severe asthma and severe refractory asthma was 25.6% (95% confidence interval [CI], 23.1-28.3) and 4.6% (95% CI, 3.5-6.0), respectively. Patients with severe asthma were (nonsevere vs severe vs severe refractory) older (39, 42, 45 years, P = .011), had high skin prick test reactivity (67.1%, 76.0%, 76.0%, P = .004), had lower forced expiratory volume in 1 second percentage (81%, 61%, 55.5%, P < .001), had lower quality of life score (129, 127 vs 121, P < .001), and had higher activity impairment (10%, 30%, 50%, P < .001). Factors independently associated with severe asthma were hypertension comorbidity; adjusted odds ratio 2.21 (1.10-4.47), P = .027, high bronchial hyperresponsiveness questionnaire score; adjusted odds ratio 2.16 (1.01-4.61), P = .047 and higher ACQ score at baseline 2.80 (1.55-5.08), P = .001.

Conclusion

The prevalence of severe asthma in Africa is high and is associated with high morbidity and poor quality of life.

Blocking CD226 regulates type 2 innate lymphoid cell effector function and alleviates airway hyperreactivity

BACKGROUND

Type 2 innate lymphoid cells (ILC2s) play a pivotal role in type 2 asthma. CD226 is a costimulatory molecule involved in various inflammatory diseases.

OBJECTIVE

We aimed to investigate CD226 expression and function within human and mouse ILC2s, and to assess the impact of targeting CD226 on ILC2-mediated airway hyperreactivity (AHR).

METHODS

We administered IL-33 intranasally to wild-type mice, followed by treatment with anti-CD226 antibody or isotype control. Pulmonary ILC2s were sorted for ex vivo analyses through RNA sequencing and flow cytometry. Next, we evaluated the effects of CD226 on AHR and lung inflammation in wild-type and Rag2-/- mice. Additionally, we compared peripheral ILC2s from healthy donors and asthmatic patients to ascertain the role of CD226 in human ILC2s.

RESULTS

Our findings demonstrated an inducible expression of CD226 in activated ILC2s, enhancing their cytokine secretion and effector functions. Mechanistically, CD226 alters intracellular metabolism and enhances PI3K/AKT and MAPK signal pathways. Blocking CD226 ameliorates ILC2-dependent AHR in IL-33 and Alternaria alternata-induced models. Interestingly, CD226 is expressed and inducible in human ILC2s, and its blocking reduces cytokine production. Finally, we showed that peripheral ILC2s in asthmatic patients exhibited elevated CD226 expression compared to healthy controls.

CONCLUSION

Our findings underscore the potential of CD226 as a novel therapeutic target in ILC2s, presenting a promising avenue for ameliorating AHR and allergic asthma.

The Efficacy & Molecular Mechanisms of a Terpenoid Compound Ganoderic Acid C1 on Corticosteroid-Resistant Neutrophilic Airway Inflammation: In vivo and in vitro Validation

Introduction

Neutrophil predominant airway inflammation is associated with severe and steroid-resistant asthma clusters. Previously, we reported efficacy of ASHMI, a three-herb TCM asthma formula in a steroid-resistant neutrophil-dominant murine asthma model and further identified Ganoderic Acid C1 (GAC1) as a key ASHMI active compound in vitro. The objective of this study is to investigate GAC1 effect on neutrophil-dominant, steroid-resistant asthma in a murine model.

Methods

In this study, Balb/c mice were systematically sensitized with ragweed (RW) and alum and intranasally challenged with ragweed. Unsensitized/PBS challenged mice served as normal controls. Post sensitization, mice were given 4 weeks of oral treatment with GAC1 or acute dexamethasone (Dex) treatment at 48 hours prior to challenge. Pulmonary cytokines were measured by ELISA, and lung sections were processed for histology by H&E staining. Furthermore, GAC1 effect on MUC5AC expression and on reactive oxygen species (ROS) production in human lung epithelial cell line (NCI-H292) was determined by qRT-PCR and ROS assay kit, respectively. Computational analysis was applied to select potential targets of GAC1 in steroid-resistant neutrophil-dominant asthma. Molecular docking was performed to predict binding modes between GAC1 and Dex with TNF-α.

Results

The result of the study showed that chronic GAC1 treatment, significantly reduced pulmonary inflammation (P < 0.01-0.001 vs Sham) and airway neutrophilia (P < 0.01 vs Sham), inhibited TNF-α, IL-4 and IL-5 levels (P < 0.05-0.001 vs Sham). Acute Dex treatment reduced eosinophilic inflammation and IL-4, IL-5 levels, but had no effect on neutrophilia and TNF-α production. GAC1 treated H292 cells showed decreased MUC5AC gene expression and production of ROS (P < 0.001 vs stimulated/untreated cells). Molecular docking results showed binding energy of complex GAC1-TNF was -10.8 kcal/mol.

Discussion

GAC1 may be a promising anti-asthma botanical drug for treatment of steroid-resistant asthma.

Tezepelumab for Severe Asthma: One Drug Targeting Multiple Disease Pathways and Patient Types

Asthma is a heterogeneous inflammatory disease of the airways, affecting many children, adolescents, and adults worldwide. Up to 10% of people with asthma have severe disease, associated with a higher risk of hospitalizations, greater healthcare costs, and poorer outcomes. Patients with severe asthma generally require high-dose inhaled corticosteroids and additional controller medications to achieve disease control; however, many patients remain uncontrolled despite this intensive treatment. The treatment of severe uncontrolled asthma has improved with greater understanding of asthma pathways and phenotypes as well as the advent of targeted biologic therapies. Tezepelumab, a monoclonal antibody, blocks thymic stromal lymphopoietin, an epithelial cytokine that has multifaceted effects on the initiation and persistence of asthma inflammation and pathophysiology. Unlike other biologic treatments, tezepelumab has demonstrated efficacy across severe asthma phenotypes, with the magnitude of effects varying by phenotype. Here we describe the anti-inflammatory effects and efficacy of tezepelumab across the most relevant phenotypes of severe asthma. Across clinical studies, tezepelumab reduced annualized asthma exacerbation rates versus placebo by 63-71% in eosinophilic severe asthma, by 58-68% in allergic severe asthma, by 67-71% in allergic and eosinophilic severe asthma, by 34-49% in type 2-low asthma, and by 31-41% in oral corticosteroid-dependent asthma. Furthermore, in all these asthma phenotypes, tezepelumab demonstrated higher efficacy in reducing exacerbations requiring hospitalizations or emergency department visits versus placebo. In patients with severe uncontrolled asthma, who commonly have multiple drivers of inflammation and disease, tezepelumab may modulate airway inflammation more extensively, as other available biologics block only specific downstream components of the inflammatory cascade.

Efficacy of mepolizumab and omalizumab combination therapy in uncontrolled asthma

OBJECTIVE

Results of biological therapies are often encouraging for severe asthma who are phenotyped as Type 2 inflammation. Unfortunately, some patients do not achieve the desired responses. In this group of patients, there are often switches between anti Ig E and anti-IL-5s and partial improvements are often is deemed sufficient.

METHOD

We planned to start combination therapy with mepolizumab and omalizumab in a 52-year-old patient with uncontrolled allergic asthma whose asthma could not be controlled with omalizumab and mepolizumab treatment, respectively. After complete asthma control was achieved, we aimed to discontinue mepolizumab and continue with omalizumab because it was allergic asthma.

RESULT

The combination of omalizumab 300 mg/month and mepolizumab 100 mg/month was tried and emergency admissions and oral corticosteroids were stopped. At the same time, significant improvement was observed in asthma control test, pulmonary function test and comfort of life.

CONCLUSION

Combined use of Anti-Ig E (omalizumab) and Anti IL 5 (mepolizumab) with a synergistic effect by acting through both pathways, especially in patients with allergic asthma and high levels of both total Ig E and eosinophilia, was found to be effective and no side effects were observed in long-term follow-up. Combination therapy with omalizumab and mepolizumab may become a safe option in patients with severe allergic asthma with a Type 2 inflammatory phenotype who cannot be controlled with each biologic agent.

Severe Asthma Network Italy Definition of Clinical Remission in Severe Asthma: A Delphi Consensus

Severe asthma affects about 10% of the population with asthma and is characterized by low lung function and a high count of blood leukocytes, mainly eosinophils. Various definitions are used in clinical practice and in the literature to identify asthma remission: clinical remission, inflammatory remission, and complete remission. This work highlights a consensus for asthma remission using a Delphi method. In the context of the Severe Asthma Network Italy, which accounts for 57 severe asthma centers and more than 2,200 patients, a board of six experts drafted a list of candidate statements in a questionnaire, which has been revised to minimize redundancies and ensure clear and consistent wording for the first round (R1) of the analysis. Thirty-two statements were included in the R1 questionnaire and then submitted to a panel of 80 experts, which used a 5-point Likert scale to measure agreement regarding each statement. Then, an interim analysis of R1 data was performed, and items were discussed and considered to produce a consistent questionnaire for round 2 (R2) of the analysis. Then, the board set the R2 questionnaire, which included only important topics. Panelists were asked to vote on the statements in the R2 questionnaire afterward. During R2, the criteria of complete clinical remission (the absence of the need for oral corticosteroids, symptoms, exacerbations or attacks, and pulmonary function stability) and those of partial clinical remission (the absence of the need for oral corticosteroids, and two of three criteria: the absence of symptoms, exacerbations or attacks, and pulmonary stability) were confirmed. This Severe Asthma Network Italy Delphi analysis defined a valuable and independent tool that is easy to use, to test the efficacy of different treatments in patients with severe asthma enrolled into the SANI registry.

Severity of adult-onset asthma - a matter of blood neutrophils and severe obesity

BACKGROUND

Adult-onset asthma is associated with a poor treatment response. The aim was to study associations between clinical characteristics, asthma control and treatment in adult-onset asthma.

METHODS

Previous participants within the population-based Obstructive Lung Disease in Northern Sweden studies (OLIN) were in 2019-2020 invited to clinical examinations including structured interviews, spirometry, fractional exhaled nitric oxide (FeNO), skin prick test and blood sampling. In total, n = 251 individuals with adult-onset asthma (debut >15 years of age) were identified. Uncontrolled asthma was defined according to ERS/ATS and treatment step according to GINA (2019).

RESULTS

Among individuals with uncontrolled asthma (34%), severe obesity (16.3% vs 7.9%, p = 0.041) and elevated levels of blood neutrophils, both regarding mean level of blood neutrophils (4.25*109/L vs 3.67*109/L, p = 0.003), and proportions with ≥4*109/L (49.4% vs 33.3%, p = 0.017) and ≥5*109/L (32.1% vs 13.7%, p < 0.001) were more common than among those with controlled asthma. Adding the dimension of GINA treatment step 1-5, individuals with uncontrolled asthma on step 4-5 treatment had the highest proportions of blood neutrophils ≥5*109/L (45.5%), severe obesity (BMI≥35, 26.1%), dyspnea (mMRC≥2) (34.8%), and most impaired lung function in terms of FEV1%<80% of predicted (42.9%), FEV1

CONCLUSION

This study indicates that in adult-onset asthma, primarily non-type-2 characteristics such as obesity and blood neutrophils associate with poor asthma control and higher doses of inhaled corticosteroids.

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Key Words

• Body mass index
• Eosinophils
• Epidemiology
• Follow-up studies
• Neutrophils
• Sweden

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MESH Headings

• Humans
• Adult
• Neutrophils
• Obesity, Morbid/complications
• Nitric Oxide/therapeutic use
• Asthma/drug therapy
• Eosinophils
• Obesity/complications

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Affiliation(s)

Sofia Winsa-Lindmark Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden.
Caroline Stridsman Umeå University, Department of Public Health and Clinical Medicine, The OLIN Unit, Sweden
Axel Sahlin Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden
Linnea Hedman Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden
Nikolai Stenfors Umeå University, Department of Public Health and Clinical Medicine, The OLIN Unit, Sweden
Tomi Myrberg Umeå University, Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine, Sweden
Anne Lindberg Umeå University, Department of Public Health and Clinical Medicine, The OLIN Unit, Sweden
Eva Rönmark Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden
Helena Backman Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden

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Severe asthma trajectories in adults: findings from the NORDSTAR cohort

BACKGROUND

There is limited evidence on the pathways leading to severe asthma and we are presently unable to effectively predict the progression of the disease. We aimed to describe the longitudinal trajectories leading to severe asthma and to describe clinical events preceding disease progression in a nationwide population of patients with severe asthma.

METHODS

We conducted an observational study based on Swedish data from the NORdic Dataset for aSThmA Research (NORDSTAR) research collaboration platform. We identified adult patients with severe asthma in 2018 according to the European Respiratory Society/American Thoracic Society definition and used latent class analysis to identify trajectories of asthma severity over a 10-year retrospective period from 2018.

RESULTS

Among 169 128 asthma patients, we identified 4543 severe asthma patients. We identified four trajectories of severe asthma that were labelled as: trajectory 1 "consistently severe asthma" (n=389 (8.6%)), trajectory 2 "gradual onset severe asthma" (n=942 (20.7%)), trajectory 3 "intermittent severe asthma" (n=1685 (37.1%)) and trajectory 4 "sudden onset severe asthma" (n=1527 (33.6%)). "Consistently severe asthma" had a higher daily inhaled corticosteroid dose and more prevalent osteoporosis compared with the other trajectories. Patients with "gradual onset severe asthma" and "sudden onset severe asthma" developed type 2-related comorbidities concomitantly with development of severe asthma. In the latter group, this primarily occurred within 1-3 years preceding onset of severe asthma.

CONCLUSIONS

Four distinct trajectories of severe asthma were identified illustrating different patterns of progression of asthma severity. This may eventually enable the development of better preventive management strategies in severe asthma.

Multiple manifestations of uncontrolled asthma increase the risk of severe COVID-19

OBJECTIVE

Asthma control is of importance when assessing the risk of severe outcomes of COVID-19. The aim of this study was to explore associations of clinical characteristics and the effect of multiple manifestations of uncontrolled asthma with severe COVID-19.

METHODS

In 2014-2020, adult patients with uncontrolled asthma, defined as Asthma Control Test (ACT) ≤19 were identified in the Swedish National Airway Register (SNAR) (n = 24533). The SNAR database, including clinical data, was linked with national registers to identify patients with severe COVID-19 (n = 221). The effect of multiple manifestations of uncontrolled asthma was based on: 1) ACT ≤15, 2) frequent exacerbations and 3) previous asthma inpatient/secondary care and evaluated stepwise. Poisson regression analyses were conducted with severe COVID-19 as the dependent variable.

RESULTS

In this cohort with uncontrolled asthma, obesity was the strongest independent risk factor for severe COVID-19 in both sexes, but even greater in men. Multiple manifestations of uncontrolled asthma were more common among those with severe COVID-19 vs. without: one, 45.7 vs. 42.3%, two, 18.1 vs. 9.1% and three, 5.0 vs. 2.1%. The risk ratio (RR) of severe COVID-19 increased with an increasing number of manifestations of uncontrolled asthma: one, RR 1.49 (95% CI 1.09-2.02), two, RR 2.42 (95% CI 1.64-3.57) and three, RR 2.96 (95% CI 1.57-5.60), when adjusted for sex, age, and BMI.

CONCLUSIONS

It is important to consider the effect of multiple manifestations of uncontrolled asthma and obesity when assessing patients with COVID-19, as this increases the risk of severe outcomes substantially.

Inhaled anti-TSLP antibody fragment, ecleralimab, blocks responses to allergen in mild asthma

BACKGROUND

Thymic stromal lymphopoietin (TSLP) is a key upstream regulator driving allergic inflammatory responses. We evaluated the efficacy and safety of ecleralimab, a potent inhaled neutralising antibody fragment against human TSLP, using allergen inhalation challenge (AIC) in subjects with mild atopic asthma.

METHODS

This was a 12-week, randomised, double-blind, placebo-controlled, parallel-design, multicentre allergen bronchoprovocation study conducted at 10 centres across Canada and Germany. Subjects aged 18-60 years with stable mild atopic asthma were randomised (1:1) to receive 4 mg once-daily inhaled ecleralimab or placebo. Primary end-points were the allergen-induced change in forced expiratory volume in 1 s (FEV₁) during the late asthmatic response (LAR) measured by area under the curve (AUC_3-7h) and maximum percentage decrease (LAR%) on day 84, and the safety of ecleralimab. Allergen-induced early asthmatic response (EAR), sputum eosinophils and fractional exhaled nitric oxide (F _ENO) were secondary and exploratory end-points.

RESULTS

28 subjects were randomised to ecleralimab (n=15) or placebo (n=13). On day 84, ecleralimab significantly attenuated LAR AUC_3-7h by 64% (p=0.008), LAR% by 48% (p=0.029), and allergen-induced sputum eosinophils by 64% at 7 h (p=0.011) and by 52% at 24 h (p=0.047) post-challenge. Ecleralimab also numerically reduced EAR AUC_0-2h (p=0.097) and EAR% (p=0.105). F _ENO levels were significantly reduced from baseline throughout the study (p<0.05), except at 24 h post-allergen (day 43 and day 85). Overall, ecleralimab was safe and well tolerated.

CONCLUSION

Ecleralimab significantly attenuated allergen-induced bronchoconstriction and airway inflammation, and was safe in subjects with mild atopic asthma.

Landscape of short-acting beta-agonists (SABA) overuse in Europe

This review article provides an overview of short-acting beta-agonist (SABA) use and prescribing trends in Europe, summarizing updated data on the results from the industry-funded SABINA program (SABA use IN asthma) and other studies on this matter. SABA use continues to increase worldwide. Overuse has been defined as ≥3 canisters/year. Almost a third of European patients with asthma, at all severity levels, overuse SABA. Guidelines recommend close monitoring of patients who overuse SABA and avoiding over-reliance on SABA monotherapy. SABA overuse is associated with increased risk of asthma exacerbations and mortality, increased use of health services and negative physical and mental health outcomes. Reliance on SABA monotherapy can be unsafe and therefore it is necessary to change asthma treatment approaches and policies. Changes in physician and patient behaviours towards SABA use are required to ensure that patients with asthma are not over-reliant on SABA monotherapy. Notwithstanding, the limitations of the studies on the use of SABA should be considered, taking into account that the prescription/purchase of medication canisters does not always represent the actual use of the medication and that associations between SABA overuse and poor asthma outcomes may not be directly causal. National health systems and asthma guidelines must align asthma management with global recommendations and adjust them to local needs.

Severe Fungal Asthma: A Role for Biologics and Inhaled Antifungals

Allergic asthma has traditionally been treated with inhaled and systemic glucocorticosteroids. A continuum of allergic fungal airways disease associated with Aspergillus fumigatus colonization and/or atopic immune responses that encompasses fungal asthma, severe asthma with fungal sensitization and allergic bronchopulmonary aspergillosis is now recognized along a phenotypic severity spectrum of T2-high immune deviation lung disease. Oral triazoles have shown clinical, anti-inflammatory and microbiologic efficacy in this setting; in the future inhaled antifungals may improve the therapeutic index. Humanized monoclonal antibody biologic agents targeting T2-high disease also show efficacy and promise of improved control in difficult cases. Developments in these areas are highlighted in this overview.

Improvement in severe asthma patients receiving biologics and factors associated with persistent insufficient control: a real-life national study

BACKGROUND

Biological therapies have revolutionized the treatment of severe asthma with type 2 inflammation. Although such treatments are very effective in reducing exacerbation and the dose of oral steroids, little is known about the persistence of symptoms in severe asthma patients treated with biologics.

PURPOSE

We aim to describe asthma control and healthcare consumption of severe asthma patients treated with biologics.

DESIGN

The Second Souffle study is a real-life prospective observational study endorsed by the Clinical Research Initiative in Severe Asthma: a Lever for Innovation & Science Network.

METHODS

Adults with a confirmed diagnosis of severe asthma for at least 12 months' duration were enrolled in the study. A self-administered questionnaire including the Asthma Control Questionnaire (ACQ), Asthma Quality of Life Questionnaire (AQLQ) and a compliance evaluation test was given to the patients. Healthcare consumption within 12 months prior to enrolment was documented. In patients receiving biologics, doctors indicated whether the patients were biologic responders or non-responders.

RESULTS

The characteristics of 431 patients with severe asthma were analysed. Among them, 409 patients (94.9%) presented asthma with type 2 inflammation (T2 high) profile, and 297 (72.6%) patients with a T2 high phenotype were treated with a biologic. Physicians estimated that 88.2% of patients receiving biologics were responders. However, asthma control was only achieved in 25.3% of those patients (ACQ > 0.75). A high proportion of patients (77.8%) identified as responders to biologics were not controlled according to the ACQ score. About 50% of patients continue to use oral corticosteroids either daily (25.2%) or more than three times a year for at least three consecutive days (25.6%). Gastro-oesophageal Reflux Disease (GERD) and Obstructive Sleep Apnoea syndrome (OSA) were identified as independent factors associated with uncontrolled asthma.

CONCLUSION

Although a high proportion of severe asthma patients respond to biologics, only 25.3% have controlled asthma. GERD and OSA are independent factors of uncontrolled asthma.

Asthma Prevalence and Phenotyping in the General Population: The LEAD (Lung, hEart, sociAl, boDy) Study

Background

Asthma is a chronic heterogeneous respiratory disease involving differential pathophysiological pathways and consequently distinct asthma phenotypes.

Objective and Methods

In the LEAD Study, a general population cohort (n=11.423) in Vienna ranging from 6-82 years of age, we addressed the prevalence of asthma and explored inflammatory asthma phenotypes that included allergic and non-allergic asthma, and within these phenotypes, an eosinophilic (eosinophils ≥300 cells/µL, or ≥150 cells/µL in the presence of ICS medication) or non-eosinophilic (eosinophils <300 cells/µL, or <150 cells/µL in the presence of ICS) phenotype. In addition, we compared various factors related to biomarkers, body composition, lung function, and symptoms in control subjects versus subjects with current asthma (current doctor's diagnosis of asthma).

Results

An overall prevalence of 4.6% was observed for current asthma. Furthermore, an age-dependent shift from allergic to non-allergic asthma was found. The non-eosinophilic phenotype was more prominent. Obesity was a prevalent condition, and body composition including visceral adipose tissue (VAT), is affected in current asthma versus controls.

Conclusion

This broad-aged and large general population cohort identified differential patterns of inflammatory asthma phenotypes that were age-dependent. The presence of eosinophilia was associated with worse asthma control, increased asthma medication, increased VAT, and lower lung function, the opposite was found for the presence of an allergic asthma.

Phenotypes and Endotypes in Asthma

Asthma is a broadly encompassing diagnosis of airway inflammation with significant variability in presentation and response. Advances in molecular techniques and imaging have unraveled the delicate mechanistic tapestry responsible for the underlying inflammatory pathways in asthma. The elucidation of biomarkers and cellular components specific to these inflammatory pathways allowed for the categorization of asthma from generic phenotypes to more specific mechanistic endotypes, with two prominent subgroups emerging based on the level of Type 2 inflammation present - T2 high and T2 low (or non-T2). Sophisticated modeling and cluster analyses using a combination of clinical, physiologic, and biomarker parameters have permitted the identification of subendotypes within the broader T2 umbrella. This mechanistic-driven classification schema for asthma has dramatically altered the landscape of asthma management with the discovery and approval of targeted biologic therapies and has ushered in a new era of personalized precision medicine in asthma.

Monoclonal antibodies in the management of asthma: Dead ends, current status and future perspectives

Patients with moderate-to-severe asthma may now be treated using a variety of monoclonal antibodies that target key inflammatory cytokines involved in disease pathogenesis. Existing clinical data on anti-IgE, anti-IL-5 and other immunological pathways indicate these therapies to offer reduced exacerbation rates, improved lung function, greater asthma control and better quality of life. However, as several patients still do not achieve satisfactory clinical response with the antibodies available, many more biologics, aiming different immunological pathways, are under evaluation. This review summarizes recent data on existing and potential monoclonal antibodies in asthma. Recent advances have resulted in the registration of a new antibody targeting TSLP (tezepelumab), with others being under development. Some of the researched monoclonal antibodies (e.g. anti-IL-13 tralokinumab and lebrikizumab or anti-IL-17A secukinumab) have shown optimistic results in preliminary research; however, these have been discontinued in asthma clinical research. In addition, as available monoclonal antibody treatments have shown little benefit among patients with T₂-low asthma, research continues in this area, with several antibodies in development. This article summarizes the available pre-clinical and clinical data on new and emerging drugs for treating severe asthma, discusses discontinued treatments and outlines future directions in this area.

Determinants of Severe Asthma - A Long-Term Cohort Study in Northern Sweden

Background

Risk factors for severe asthma are not well described. The aim was to identify clinical characteristics and risk factors at study entry that are associated with severe asthma at follow-up in a long-term prospective population-based cohort study of adults with asthma.

Methods

Between 1986 and 2001, 2055 adults with asthma were identified by clinical examinations of population-based samples in northern Sweden. During 2012-2014, n = 1006 (71% of invited) were still alive, residing in the study area and participated in a follow-up, of which 40 were identified as having severe asthma according to ERS/ATS, 131 according to GINA, while 875 had other asthma. The mean follow-up time was 18.7 years.

Results

Obesity at study entry and adult-onset asthma were associated with severe asthma at follow-up. While severe asthma was more common in those with adult-onset asthma in both men and women, the association with obesity was observed in women only. Sensitization to mites and moulds, but not to other allergens, as well as NSAID-related respiratory symptoms was more common in severe asthma than in other asthma. Participants with severe asthma at follow-up had lower FEV₁, more pronounced FEV₁ reversibility, and more wheeze, dyspnea and nighttime awakenings already at study entry than those with other asthma.

Conclusion

Adult-onset asthma is an important risk factor for development of severe asthma in adults, and obesity increased the risk among women. The high burden of respiratory symptoms already at study entry also indicate long-term associations with development of severe asthma.

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

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

Clinical implications of asthma endotypes and phenotypes

Background: Asthma is a complex disorder with variable clinical expression. Recognizable clinical and laboratory features define phenotypes, and specific biologic pathways define endotypes. Identifying the specific pathway responsible for persistent asthma would enable the clinician to select the optimal inhibitors, which currently are biologic therapies. Objective: To provide an up-to-date review of the current clinical status of endotype and phenotype characterizations of asthma and discuss these categories in relation to the available, or likely available, biologic therapies for asthma. Methods: The medical literature was reviewed based on the search terms: asthma biologics, severe asthma, uncontrolled asthma, corticosteroid-dependent asthma, phenotype, endotype, and type 2. We also used our knowledge of the literature and current research. Results: All of the current biologics, including the recently approved tezepelumab, were most effective with increased type 2 biomarkers, which identify exacerbation-prone asthma. Current biomarkers do not permit consistent identification of specific endotypes to facilitate informed selection of the optimal therapy for an individual patient. Thus, empiricism and the art of care continue to play major roles in treatment selection. Conclusion: Current biologic therapies for asthma and those likely to be U.S. Food and Drug Administration approved within the near future work best in subjects with strong type 2 signatures. Available biomarkers and observable characteristics do not enable clinicians to recognize specific endotypes, but rather subphenotypes or overlapping endotypes. The goal of identifying the optimal patient for a specific therapy remains elusive, but worthy of pursuit. In the interim, the availability of an increasing number of treatment options allows the clinician to help most of his or her patients.

Optimizing asthma management: Role of long-acting muscarinic antagonists

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

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

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.

Association of serum surfactant protein D and SFTPD gene variants with asthma in Danish children, adolescents, and young adults

BACKGROUND

Surfactant Protein D (SP-D) is a pattern recognition molecule belonging to the family of collectins expressed in multiple human organ systems, including the lungs. Previous studies have shown that SP-D levels in bronchoalveolar lavage samples decrease and serum levels increase in patients suffering from asthma, possibly due to a combination of induced SP-D synthesis and decreased air-blood barrier integrity. The aims of this study were to investigate whether serum levels of SP-D and common variants in the SP-D gene were associated with asthma in adolescents and young adults.

METHODS

Prospective observational study including 449 adolescents and young adults (age 11-27 years) previously diagnosed with asthma during a 2-year period from 2003 to 2005 (0-16 years). At follow-up from 2016 to 2017, 314 healthy controls with no history of asthma were recruited. Serum SP-D was analyzed on samples obtained at baseline as well as samples obtained at follow-up. SP-D genotyping was performed for rs721917, rs2243639, and rs3088308.

RESULTS

No differences were found in mean levels of sSP-D and SFTPD genotype among subjects with current asthma, no current asthma, and controls. Serum SP-D and SFTPD genotype were not associated with any clinical parameters of asthma. Furthermore, baseline sSP-D was not associated with asthma at follow-up.

CONCLUSION

Serum surfactant protein D and common SP-D gene variants were not associated with asthma in Danish adolescents and young adults with mild to moderate asthma. Serum surfactant protein D did not demonstrate any value as a clinical biomarker of asthma.

Effects of azithromycin on bronchial remodeling in the natural model of severe neutrophilic asthma in horses

Steroid resistance in asthma has been associated with neutrophilic inflammation and severe manifestations of the disease. Macrolide add-on therapy can improve the quality of life and the exacerbation rate in refractory cases, possibly with greater effectiveness in neutrophilic phenotypes. The mechanisms leading to these beneficial effects are incompletely understood and whether macrolides potentiate the modulation of bronchial remodeling induced by inhaled corticosteroids (ICS) is unknown. The objective of this study was to determine if adding azithromycin to ICS leads to further improvement of lung function, airway inflammation and bronchial remodeling in severe asthma. The combination of azithromycin (10 mg/kg q48h PO) and inhaled fluticasone (2500 µg q12h) was compared to the sole administration of fluticasone for five months in a randomized blind trial where the lung function, airway inflammation and bronchial remodeling (histomorphometry of central and peripheral airways and endobronchial ultrasound) of horses with severe neutrophilic asthma were assessed. Although the proportional reduction of airway neutrophilia was significantly larger in the group receiving azithromycin, the lung function and the peripheral and central airway smooth muscle mass decreased similarly in both groups. Despite a better control of airway neutrophilia, azithromycin did not potentiate the other clinical effects of fluticasone.

Respiratory-related death in individuals with incident asthma and COPD: a competing risk analysis

Background

Distinguishing between mortality attributed to respiratory causes and other causes among people with asthma, COPD, and asthma-COPD overlap (ACO) is important. This study used electronic health records in England to estimate excess risk of death from respiratory-related causes after accounting for other causes of death.

Methods

We used linked Clinical Practice Research Datalink (CPRD) primary care and Office for National Statistics mortality data to identify adults with asthma and COPD from 2005 to 2015. Causes of death were ascertained using death certificates. Hazard ratios (HR) and excess risk of death were estimated using Fine-Gray competing risk models and adjusting for age, sex, smoking status, body mass index and socioeconomic status.

Results

65,021 people with asthma and 45,649 with COPD in the CPRD dataset were frequency matched 5:1 with people without the disease on age, sex and general practice. Only 14 in 100,000 people with asthma are predicted to experience a respiratory-related death up to 10 years post-diagnosis, whereas in COPD this is 98 in 100,000. Asthma is associated with an 0.01% excess incidence of respiratory related mortality whereas COPD is associated with an 0.07% excess. Among people with asthma-COPD overlap (N = 22,145) we observed an increased risk of respiratory-related death compared to those with asthma alone (HR = 1.30; 95% CI 1.21–1.40) but not COPD alone (HR = 0.89; 95% CI 0.83–0.94).

Conclusions

Asthma and COPD are associated with an increased risk of respiratory-related death after accounting for other causes; however, diagnosis of COPD carries a much higher probability. ACO is associated with a lower risk compared to COPD alone but higher risk compared to asthma alone.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01823-4.

Thymic stromal lymphopoietin and alarmins as possible therapeutical targets for asthma

PURPOSE OF REVIEW

Overview of epithelial cytokines, particularly thymic stromal lymphopoietin (TSLP), released by the airway epithelium and the effects of their inhibition on the outcomes of patients with asthma.

RECENT FINDINGS

The epithelial cytokines are early mediators at the top of the inflammatory cascade and are attractive therapeutic targets to prevent exacerbations and improve lung function in patients with type 2 and nontype 2 asthma.

SUMMARY

Clinical trials demonstrated that tezepelumab, an anti-TSLP monoclonal antibody, is a promising alternative treatment for asthma that is effective also in nontype 2 asthma. The PATHWAY and NAVIGATOR trials have assessed its effects in improving outcomes on broad clinically diverse populations. The identification of biomarkers will help to predict potential responders and help in asthma treatment personalization.

The role of systemic corticosteroids in severe asthma and new evidence in their management and tapering

INTRODUCTION

Based on the latest literature evidence, between 30% and 60% of adults with severe refractory asthma (SRA) are systemic corticosteroid (SCS) dependent. There are numerous therapeutic options in asthma, which are often not effective in severe forms. In these cases, SCS should be considered, but it is increasingly recognized that their regular use is often associated with significant and potentially serious adverse events.

AREAS COVERED

The aim of this article is to provide an update about the recent and significant literature on SCS and to establish their role in the management of SRA. We summarized the most important and recent evidence and we provided useful indications for clinicians.

EXPERT OPINION

There is now strong evidence supporting the increased risk of comorbidities and complications with long-term SCS therapies, regardless of the dose. New evidence on SCS tapering and withdrawal will allow to define protocols to address SCS management with greater safety and effectiveness, after starting efficient steroid-sparing strategies. In the next 5years, it will be necessary to implement corrective actions to address these unmet needs, to reduce the inappropriate use of SCS by maximizing the application of more innovative and effective therapies.

Severe Asthma in a General Population Study: Prevalence and Clinical Characteristics

PURPOSE

Current guidelines primarily use medication levels to distinguish severe asthma from other types of asthma. In addition, severe asthma must also be uncontrolled at high-intensity treatment or become uncontrolled if treatment level is decreased. To date, only a few studies have used this definition to investigate the prevalence and clinical characteristics of severe asthma in population-based samples. Therefore, the aim of this study was to evaluate the prevalence and clinical characteristics of individuals with severe asthma in the population-representative West Sweden Asthma Study.

MATERIALS AND METHODS

In this cross-sectional population-based study, a randomly selected sample (n=1172) and a separate asthma sample (n=744) underwent clinical examinations, completed a structured interview and responded to questionnaires. Severe asthma was defined as at least one feature of uncontrolled asthma despite treatment in line with the Global Initiative for Asthma (GINA) steps 4/5. This treatment level required a minimum medium dose of inhaled corticosteroids (ICS) plus a second controller or oral corticosteroids.

RESULTS

The prevalence of severe asthma was 1.1% in the adult random sample and 9.5% within the asthma sample. Individuals with severe asthma were older and had more symptoms, activity limitations, heart disease and blood neutrophils compared to those with other asthma. They also had lower lung function and despite these impairments, 32% did not have annual contact with a healthcare provider.

CONCLUSION

The prevalence of severe asthma was higher compared to previous studies, and many individuals with severe asthma did not have regular contact with healthcare providers. Due to the high burden of symptoms and impairments for individuals with severe asthma, it is important that the healthcare system implement strategies to improve follow-up and evaluate these patients according to existing guidelines.

Pharmacological Rationale for Targeting IL-17 in Asthma

Asthma is a respiratory disease that currently affects around 300 million people worldwide and is defined by coughing, shortness of breath, wheezing, mucus overproduction, chest tightness, and expiratory airflow limitation. Increased levels of interleukin 17 (IL-17) have been observed in sputum, nasal and bronchial biopsies, and serum of patients with asthma compared to healthy controls. Patients with higher levels of IL-17 have a more severe asthma phenotype. Biologics are available for T helper 2 (Th2)-high asthmatics, but the Th17-high subpopulation has a relatively low response to these treatments, rendering it a rather severe asthma phenotype to treat. Several experimental models suggest that targeting the IL-17 pathway may be beneficial in asthma. Moreover, as increased activation of the Th17/IL-17 axis is correlated with reduced inhaled corticosteroids (ICS) sensitivity, targeting the IL-17 pathway might reverse ICS unresponsiveness. In this review, we present and discuss the current knowledge on the role of IL-17 in asthma and its interaction with the Th2 pathway, focusing on the rationale for therapeutic targeting of the IL-17 pathway.

Attitudes of Croatian pulmonologists concerning obstacles to earlier, more appropriate use of biologics in severe asthma: Survey results

AIMS

Biologics have been proven efficacious for patients with severe asthma (SA). It is essential to diagnose such individuals correctly. This study was designed to survey pulmonologists to identify barriers to early diagnosis and subsequent appropriate use of biologics for SA in Croatia.

METHODS

A pulmonologist group with expertise in SA developed the initial list of questions, with the final questionnaire created according to a 2-round Delphi method. The resulting survey consisted of 23 items consequently divided into 4 domains: 1) Pulmonologists' demographics and professional experiences; 2) Concerns about asthma management; 3) Attitudes toward SA diagnosis; and 4) Beliefs and attitudes regarding the use of biologics in managing SA. The given answers represented the respondents' estimates.

RESULTS

Eighty-four surveys were analyzed, with pulmonologists observing that general practitioners often inaccurately diagnose asthma and treat acute exacerbations. Although specialist centers are capably and correctly equipped, the time to diagnose patients with SA is approximately 3.5 months, with initial use of biologics delayed an additional 2 months. The primary indications for prescribing biologics are conventional therapy with oral glucocorticoids (91.7%) and frequent acute exacerbations (82.1%). In addition to improper diagnosis (64.3%), many patients with SA do not receive the indicated biologics owing to strict administrative directives for reimbursement (70.2%) or limited hospital resources (57.1%).

LIMITATIONS

The limitations of this survey include the subjective nature of the collected data, the relatively small sample size, and the lack of the biologic efficacy evaluation.

CONCLUSIONS

Croatian pulmonologists observed that a significant number of patients with SA who are eligible for biologics are not prescribed them, largely because of an inaccurate and/or delayed diagnosis, a delayed referral to a specialist center, highly restrictive criteria for reimbursement, and/or institutional budgetary limitations.