International ERS/ATS guidelines on definition, evaluation and treatment of severe asthma

Comparison of Long-term Response and Remission to Omalizumab and Anti-IL-5/IL-5R Using Different Criteria in a Real-life Cohort of Severe Asthma Patients

BACKGROUND

Evaluation of biologic therapy response is vital to monitor its effectiveness. Authors have proposed various response criteria including good responder, super-responder, non-responder, and clinical remission.

OBJECTIVES

To ascertain the prevalence of response and clinical remission after long-term treatment (>6 months) of anti-IgE and anti-IL-5/IL-5Rα biologics, compare these results with existing criteria, and identify predictors for non-responders and clinical remission.

METHODS

A multicenter, real-life study involving severe asthma patients in Spain. Various outcomes were assessed to gauge response and clinical remission against established criteria.

RESULTS

The study included 429 patients, 209 (48.7%) omalizumab, 112 (26.1%) mepolizumab, 19 (4.4%) reslizumab and 89 (20.7%) benralizumab, with a mean treatment duration of 55.3±38.8 months. In the final year of treatment, 218 (50.8%) were super-responders, 173 (40.3%) responders, 38 (8.9%) non-responders, and clinical remission in 116 (27%), without differences among biologics. The short-term non-responders (<6 months) were 25/545 (4.6%). Substantial variations in response and clinical remission were observed when applying different published criteria. Predictors of non-response included higher BMI (OR:1.14; 95% CI:1.06-1.23; p<0.001), admissions at ICU (2.69; 1.30-5.56; p=0.01), high count of SAE (1.21; 1.03-1.42; p=0.02) before biologic treatment. High FEV1% (0.96; 0.95-0.98; p<0.001), a high ACT score (0.93; 0.88-0.99; p=0.01) before biologic treatment or NSAID-ERD (0.52; 0.29-0.91; p=0.02) showed strong associations with achieving clinical remission.

CONCLUSION

A substantial proportion of severe asthma patients treated long-term with omalizumab or anti-IL5/IL-5Rα achieved a good response. Differences in response criteria highlight the need for harmonization in defining response and clinical remission in biologic therapy to enable meaningful cross-study comparisons.

Structural and functional features of asthma participants with fixed airway obstruction using CT imaging and 1D computational fluid dynamics: A feasibility study

Asthma with fixed airway obstruction (FAO) is associated with significant morbidity and rapid decline in lung function, making its treatment challenging. Quantitative computed tomography (QCT) along with data postprocessing is a useful tool to obtain detailed information on airway structure, parenchymal function, and computational flow features. In this study, we aim to identify the structural and functional differences between asthma with and without FAO. The FAO group was defined by a ratio of forced expiratory volume in 1 s (FEV1 ) to forced vital capacity (FVC), FEV1 /FVC <0.7. Accordingly, we obtained two sets of QCT images at inspiration and expiration of asthma subjects without (N = 24) and with FAO (N = 12). Structural and functional QCT-derived airway variables were extracted, including normalized hydraulic diameter, normalized airway wall thickness, functional small airway disease, and emphysema percentage. A one-dimensional (1D) computational fluid dynamics (CFD) model considering airway deformation was used to compare the pressure distribution between the two groups. The computational pressures showed strong correlations with the pulmonary function test (PFT)-based metrics. In conclusion, asthma participants with FAO had worse lung functions and higher-pressure drops than those without FAO.

The Impact of Airway Obstruction on Feno Values in Asthma Patients

BACKGROUND

Exhaled nitric oxide (Feno) is used as a marker of type-2 airway inflammation in asthma management. Studies with airway challenges demonstrated that a reduction in airway caliber decreases Feno levels.

OBJECTIVE

To evaluate the impact of airway caliber reduction occurring spontaneously in patients with asthma on Feno values in daily clinical practice.

METHODS

In this post hoc analysis, Feno, FEV1, and asthma control questionnaire scores were recorded on each visit for 120 (1073 visits) adult patients with asthma. Blood eosinophils were measured intermittently. The intraindividual relationship between Feno and FEV1 was evaluated via a linear mixed model. The determinants of the individual mean Feno were measured by a stepwise multivariate linear model including individual mean FEV1, inhaled corticosteroid dose, asthma control questionnaire score, and blood eosinophils.

RESULTS

Variations in the negative Feno-FEV1 relationship within individuals at different times were significantly determined by the individual's mean FEV1. This relationship did not hold for individuals above the 75th and below the 25th quartiles. The best explanatory variables for individual mean Feno were FEV1 (+4.3 parts per billion/10%pred) and blood eosinophil count (+1 part per billion per 100 cells/mm3).

DISCUSSION

In the presence of variable degrees of heterogeneous patterns of airway inflammation, airway caliber is shown to be an independent and significant determinant of Feno when measured in patients with asthma. We would propose a +4-parts-per-billion correction factor to the measured Feno value for each 10% reduction below 100% predicted FEV1. Doing this should improve the rigor of interpretation of Feno as an indicator of type-2 inflammation in patients with low FEV1.

CYP27A1-27-hydroxycholesterol axis in the respiratory system contributes to house dust mite-induced allergic airway inflammation

BACKGROUND

27-Hydroxycholesterol (27-HC) derived from sterol 27-hydroxylase (CYP27A1) has pro-inflammatory biological activity and is associated with oxidative stress and chronic inflammation in COPD. However, the role of regulation of CYP27A1- 27-HC axis in asthma is unclear. This study aimed to elucidate the contribution of the axis to the pathophysiology of asthma.

METHODS

House dust mite (HDM) extract was intranasally administered to C57BL/6 mice and the expression of CYP27A1 in the airways was analyzed by immunostaining. The effect of pre-treatment with PBS or CYP27A1 inhibitors on the cell fraction in the bronchoalveolar lavage fluid (BALF) was analyzed in the murine model. In vitro, BEAS-2B cells were treated with HDM and the levels of CYP27A1 expression were examined. Furthermore, the effect of 27-HC on the expressions of E-cadherin and ZO-1 in the cells was analyzed. The amounts of RANTES and eotaxin from the 27-HC-treated cells were analyzed by ELISA.

RESULTS

The administration of HDM increased the expression of CYP27A1 in the airways of mice as well as the number of eosinophils in the BALF. CYP27A1 inhibitors ameliorated the HDM-induced increase in the number of eosinophils in the BALF. Treatment with HDM increased the expression of CYP27A1 in BEAS-2B cells. The administration of 27-HC to BEAS-2B cells suppressed the expression of E-cadherin and ZO-1, and augmented the production of RANTES and eotaxin.

CONCLUSIONS

The results of this study suggest that aeroallergen could enhance the induction of CYP27A1, leading to allergic airway inflammation and disruption of the airway epithelial tight junction through 27-HC production.

Asthma and COPD: A Focus on β-Agonists - Past, Present and Future

Asthma has been recognised as a respiratory disorder for millennia and the focus of targeted drug development for the last 120 years. Asthma is one of the most common chronic non-communicable diseases worldwide. Chronic obstructive pulmonary disease (COPD), a leading cause of morbidity and mortality worldwide, is caused by exposure to tobacco smoke and other noxious particles and exerts a substantial economic and social burden. This chapter reviews the development of the treatments of asthma and COPD particularly focussing on the β-agonists, from the isolation of adrenaline, through the development of generations of short- and long-acting β-agonists. It reviews asthma death epidemics, considers the intrinsic efficacy of clinical compounds, and charts the improvement in selectivity and duration of action that has led to our current medications. Important β2-agonist compounds no longer used are considered, including some with additional properties, and how the different pharmacological properties of current β2-agonists underpin their different places in treatment guidelines. Finally, it concludes with a look forward to future developments that could improve the β-agonists still further, including extending their availability to areas of the world with less readily accessible healthcare.

Exploring the feasibility, acceptability, usability and safety of a digitally supported self-management intervention for uncontrolled asthma: A pre-post pilot study in secondary care

Introduction

Asthma control is often suboptimal, which is associated with incorrect medication use and poor asthma management by patients. Astmakompas, a digital self-management intervention, comprises a mobile app for patients, a web portal for healthcare professionals (HCP), and a wireless spirometer. Together, these components are intended to facilitate symptom monitoring, patient-HCP communication and assist in asthma-related self-management.

Objective

The pilot study primarily aims to assess the feasibility, acceptability, usability and safety of Astmakompas from patient and HCP perspectives, and secondarily to explore potential effects on asthma control, medication use, Quality of Life, self-efficacy and (in)direct costs.

Methods

A mixed-method, multi-center, pre-post study design was conducted in two Dutch hospitals, involving patients with uncontrolled asthma and four HCPs. Primary outcomes were assessed post-intervention using questionnaires and in-depth interviews. Secondary outcomes were assessed at baseline and post-intervention using questionnaires, and post-intervention using in-depth interviews.

Results

In general, the data show that Astmakompas was considered feasible, acceptable, usable and safe by both patients (n = 14) and HCPs (n = 4). Furthermore, qualitative data of 11 patients and all HCPs showed the importance of guidance from HCPs and tailoring of Astmakompas to care needs. Astmakompas helped patients recognise symptoms and provided valuable insights into asthma control while being easy to use. Asthma control improved from baseline (M = 2.1, SD = 1.3) to post-intervention (M = 1.3, SD = 1.0, t(13) = 2.61; p = .02).

Conclusion

Astmakompas shows promise for further implementation and research. Future randomized studies with longer evaluation periods are crucial to assess the tool's impact on asthma outcomes and workload. It is important that HCPs guide and tailor interventions to meet the patient's individual needs and circumstances.

Untangling asthma, inducible laryngeal obstruction, and dysfunctional breathing in a competitive sportsperson

A young woman with historically mild asthma experienced worsening breathlessness and cough with competitive ice skating. Despite optimizing and escalating treatment for her eosinophilic asthma, and addressing known exacerbating factors, her symptoms remained uncontrolled and refractory to bronchodilators and oral corticosteroids. Objective testing suggested her presentation was out of keeping with asthma alone, and she was suspected to have comorbid dysfunctional breathing and/or inducible laryngeal obstruction. Evidence was required to confirm the diagnoses, assess each condition's contribution to her symptom burden, and guide therapy. As exercise was a predominant trigger, she proceeded to cardiopulmonary exercise test with continuous laryngoscopy during exercise (CPET-CLE). Testing confirmed the presence of two forms of inducible laryngeal obstruction and evidence of hyperventilation predominant dysfunctional breathing. This case highlights the importance of identifying coexisting conditions in difficult-to-treat asthma, and the value of structured multidisciplinary assessment in referral centres for such individuals.

Personalized Medicine in Severe Asthma: From Biomarkers to Biologics

Severe asthma is a complex and heterogeneous clinical condition presented as chronic inflammation of the airways. Conventional treatments are mainly focused on symptom control; however, there has been a shift towards personalized medicine. Identification of different phenotypes driven by complex pathobiological mechanisms (endotypes), especially those driven by type-2 (T2) inflammation, has led to improved treatment outcomes. Combining biomarkers with T2-targeting monoclonal antibodies is crucial for developing personalized treatment strategies. Several biological agents, including anti-immunoglobulin E, anti-interleukin-5, and anti-thymic stromal lymphopoietin/interleukin-4, have been approved for the treatment of severe asthma. These biological therapies have demonstrated efficacy in reducing asthma exacerbations, lowering eosinophil count, improving lung function, diminishing oral corticosteroid use, and improving the quality of life in selected patients. Severe asthma management is undergoing a profound transformation with the introduction of ongoing and future biological therapies. The availability of novel treatment options has facilitated the adoption of phenotype/endotype-specific approaches and disappearance of generic interventions. The transition towards precision medicine plays a crucial role in meticulously addressing the individual traits of asthma pathobiology. An era of tailored strategies has emerged, allowing for the successful targeting of immune-inflammatory responses that underlie uncontrolled T2-high asthma. These personalized approaches hold great promise for improving the overall efficacy and outcomes in the management of severe asthma. This article comprehensively reviews currently available biological agents and biomarkers for treating severe asthma. With the expanding repertoire of therapeutic options, it is becoming increasingly crucial to comprehend the influencing factors, understand the pathogenesis, and track treatment progress in severe asthma.

Reduced tidal volume-inflection point and elevated operating lung volumes during exercise in females with well-controlled asthma

INTRODUCTION

Individuals with asthma breathe at higher operating lung volumes during exercise compared with healthy individuals, which contributes to increased exertional dyspnoea. In health, females are more likely to develop exertional dyspnoea than males at a given workload or ventilation, and therefore, it is possible that females with asthma may develop disproportional dyspnoea on exertion. The purpose of this study was to compare operating lung volume and dyspnoea responses during exercise in females with and without asthma.

METHODS

Sixteen female controls and 16 females with asthma were recruited for the study along with 16 male controls and 16 males with asthma as a comparison group. Asthma was confirmed using American Thoracic Society criteria. Participants completed a cycle ergometry cardiopulmonary exercise test to volitional exhaustion. Inspiratory capacity manoeuvres were performed to estimate inspiratory reserve volume (IRV) and dyspnoea was evaluated using the Modified Borg Scale.

RESULTS

Females with asthma exhibited elevated dyspnoea during submaximal exercise compared with female controls (p<0.05). Females with asthma obtained a similar IRV and dyspnoea at peak exercise compared with healthy females despite lower ventilatory demand, suggesting mechanical constraint to tidal volume (VT) expansion. VT-inflection point was observed at significantly lower ventilation and V̇O2 in females with asthma compared with female controls. Forced expired volume in 1 s was significantly associated with VT-inflection point in females with asthma (R2=0.401; p<0.01) but not female controls (R2=0.002; p=0.88).

CONCLUSION

These results suggest that females with asthma are more prone to experience exertional dyspnoea, secondary to dynamic mechanical constraints during submaximal exercise when compared with females without asthma.

A real-world pharmacovigilance study of mepolizumab in the FDA adverse event reporting system (FAERS) database

Mepolizumab is primarily used in the treatment of asthma, eosinophilic granulomatosis with polyangiitis, eosinophilia syndrome, and chronic rhinitis with nasal polyps. The information about its adverse drug reactions is mainly derived from clinical trials, and there is a shortage of real-world studies with extensive sample sizes. In this study, the U.S. FDA's Adverse Event Reporting System (FAERS) database was analyzed to evaluate the side effects of mepolizumab. A total of 18,040 reports of mepolizumab-associated adverse events were identified from the FDA Adverse Event Reporting System database. Multiple disproportionality analysis algorithms were used to determine the significance of these AEs. The study identified 198 instances of mepolizumab-induced AEs, including some important AEs not mentioned in the product labeling. The time to onset of adverse reactions was also analyzed, with a median time of 109 days. Most AEs occurred within the first month of mepolizumab use, but some may still occur after 1 year of treatment. Gender-specific analysis showed different high-risk AEs for females (digestive and neurological side effects) and males (serious adverse effects leading to hospitalization and death). The findings mentioned provide valuable insights on optimizing the use of mepolizumab, enhancing its effectiveness, and minimizing potential side effects. This information will greatly contribute to the practical implementation of the drug in clinical settings.

Anticipating undiagnosed asthma in symptomatic adults with normal pre- and post-bronchodilator spirometry: a decision tool for bronchial challenge testing

BACKGROUND

Some patients with asthma demonstrate normal spirometry and remain undiagnosed without further testing.

OBJECTIVE

To determine clinical predictors of asthma in symptomatic adults with normal spirometry, and to generate a tool to help clinicians decide who should undergo bronchial challenge testing (BCT).

METHODS

Using random-digit dialling and population-based case-finding, we recruited adults from the community with respiratory symptoms and no previous history of diagnosed lung disease. Participants with normal pre- and post-bronchodilator spirometry subsequently underwent BCT. Asthma was diagnosed in those with symptoms and a methacholine provocative concentration (PC20) of < 8 mg/ml. Sputum and blood eosinophils, and exhaled nitric oxide were measured. Univariate analyses identified potentially predictive variables, which were then used to construct a multivariable logistic regression model to predict asthma. Model sensitivity, specificity, and area under the receiver operating curve (AUC) were calculated.

RESULTS

Of 132 symptomatic individuals with normal spirometry, 34 (26%) had asthma. Of those ultimately diagnosed with asthma, 33 (97%) answered 'yes' to a question asking whether they experienced cough, chest tightness or wheezing provoked by exercise or cold air. Other univariate predictors of asthma included female sex, pre-bronchodilator FEV1 percentage predicted, and percent positive change in FEV1 post bronchodilator. A multivariable model containing these predictive variables yielded an AUC of 0.82 (95% CI: 0.72-0.91), a sensitivity of 82%, and a specificity of 66%. The model was used to construct a nomogram to advise clinicians which patients should be prioritized for BCT.

CONCLUSIONS

Four readily available patient characteristics demonstrated a high sensitivity and AUC for predicting undiagnosed asthma in symptomatic adults with normal pre- and post-bronchodilator spirometry. These characteristics can potentially help clinicians to decide which individuals with normal spirometry should be investigated with bronchial challenge testing. However, further prospective validation of our decision tool is required.

Cytotoxic CD4+ tissue-resident memory T cells are associated with asthma severity

BACKGROUND

Patients with severe uncontrolled asthma represent a distinct endotype with persistent airway inflammation and remodeling that is refractory to corticosteroid treatment. CD4+ TH2 cells play a central role in orchestrating asthma pathogenesis, and biologic therapies targeting their cytokine pathways have had promising outcomes. However, not all patients respond well to such treatment, and their effects are not always durable nor reverse airway remodeling. This observation raises the possibility that other CD4+ T cell subsets and their effector molecules may drive airway inflammation and remodeling.

METHODS

We performed single-cell transcriptome analysis of >50,000 airway CD4+ T cells isolated from bronchoalveolar lavage samples from 30 patients with mild and severe asthma.

FINDINGS

We observed striking heterogeneity in the nature of CD4+ T cells present in asthmatics' airways, with tissue-resident memory T (TRM) cells making a dominant contribution. Notably, in severe asthmatics, a subset of CD4+ TRM cells (CD103-expressing) was significantly increased, comprising nearly 65% of all CD4+ T cells in the airways of male patients with severe asthma when compared to mild asthma (13%). This subset was enriched for transcripts linked to T cell receptor activation (HLA-DRB1, HLA-DPA1) and cytotoxicity (GZMB, GZMA) and, following stimulation, expressed high levels of transcripts encoding for pro-inflammatory non-TH2 cytokines (CCL3, CCL4, CCL5, TNF, LIGHT) that could fuel persistent airway inflammation and remodeling.

CONCLUSIONS

Our findings indicate the need to look beyond the traditional T2 model of severe asthma to better understand the heterogeneity of this disease.

FUNDING

This research was funded by the NIH.

Peripheral neutrophils and oxidative stress-associated molecules for predicting the severity of asthma: a cross-sectional study based on multidimensional assessment

Objectives

This study aims to explore the relationship between the severity of asthma and neutrophils and related oxidative stress-associated molecules in peripheral blood and induced sputum.

Methods

A total of 67 subjects were included in this study, namely, 25 patients with severe asthma and 42 patients with non-severe asthma. Clinical data, induced sputum and peripheral blood were collected. Lung function and molecules related to oxidative stress in induced sputum and peripheral blood of asthma patients were detected. The relationship between neutrophils and asthma severity was analyzed. HDAC2 mRNA and protein expression levels and HDAC2 activity were also analyzed. Multivariate logistic regression was performed to select statistically significant variables.

Results

The absolute value of neutrophils and percentage of neutrophils were higher in the severe asthma patients. These two values were used to predict the severity of asthma by ROC analysis, with the best cutoff values being 4.55 × 109/L (sensitivity 83.3%, specificity 64.0%) and 55.15% (sensitivity 54.8%, specificity 88.0%). The ROS concentration of neutrophils in the induced sputum samples and the 8-iso-PGF2α concentration in the peripheral blood samples were higher in the severe asthma group (P = 0.012; P = 0.044), whereas there was reduced HDAC2 protein activity in PBMCs (P < 0.001). A logistic equation and a nomogram were created to give a precise prediction of disease severity.

Conclusion

Oxidative stress is increased in severe asthma patients. Peripheral blood neutrophils and 8-iso-PGF2α can be used as biomarkers to predict the severity of asthma. A prediction model was created for evaluating asthma severity.

Mitochondrial DNA Copy Number Variation in Asthma Risk, Severity, and Exacerbations

Rationale

Although airway oxidative stress and inflammation are central to asthma pathogenesis, there is limited knowledge of the relationship of asthma risk, severity, or exacerbations to mitochondrial dysfunction, which is pivotal to oxidant generation and inflammation.

Objectives

We investigated whether mitochondrial DNA copy number (mtDNA-CN) as a measure of mitochondrial function is associated with asthma diagnosis, severity, oxidative stress, and exacerbations.

Methods

We measured mtDNA-CN in blood in two cohorts. In the UK Biobank (UKB), we compared mtDNA-CN in mild and moderate-severe asthmatics to non-asthmatics. In the Severe Asthma Research Program (SARP), we evaluated mtDNA-CN in relation to asthma severity, biomarkers of oxidative stress and inflammation, and exacerbations.

Measures and Main Results

In UK Biobank, asthmatics (n = 29,768) have lower mtDNA-CN compared to non-asthmatics (n = 239,158) (beta, -0.026 [95% CI, -0.038 to -0.014], P = 2.46×10-5). While lower mtDNA-CN is associated with asthma, mtDNA-CN did not differ by asthma severity in either UKB or SARP. Biomarkers of inflammation show that asthmatics have higher white blood cells (WBC), neutrophils, eosinophils, fraction exhaled nitric oxide (FENO), and lower superoxide dismutase (SOD) than non-asthmatics, confirming greater oxidative stress in asthma. In one year follow-up in SARP, higher mtDNA-CN is associated with reduced risk of three or more exacerbations in the subsequent year (OR 0.352 [95% CI, 0.164 to 0.753], P = 0.007).

Conclusions

Asthma is characterized by mitochondrial dysfunction. Higher mtDNA-CN identifies an exacerbation-resistant asthma phenotype, suggesting mitochondrial function is important in exacerbation risk.

Factors influencing poor response to type 2 targeted therapies in severe asthma: a retrospective cohort study

BACKGROUND

A significant breakthrough has been made in treating severe asthma, with the recognition of various asthma phenotypes and an updated management guideline. Type 2 targeted therapies, such as benralizumab and omalizumab; have been identified as an effective treatment for severe asthma, improving patient response, lung function tests and asthma symptom control. This study aimed to evaluate factors contributing to poor response to therapy.

METHODS

A retrospective single-center cohort study of 162 patients with severe asthma who started biologic therapy; their data were retrieved from medical records for further analysis. Poor responders were patients remained clinically and functionally uncontrolled despite even after augmenting all treatment options.

RESULTS

Childhood-onset asthma, bronchiectasis, poor symptom control (ACT below 19), severe airway obstruction (< 60% predicted), and maintenance oral corticosteroid (mOCS) use were significantly associated with poor response to omalizumab and benralizumab; p = 0.0.4 and 0.01; 0.003 and 0.01; 0.01 and 0.001, 0.05 and 0.04; 0.006 and 0.02, respectively. However, chronic rhinosinusitis and IgE < 220kIU/L were associated with higher poor response rates to omalizumab (p = 0.01 and 0.04, respectively). At the same time, female patients and those with blood eosinophils level < 500 cells/mm3 had a higher poor response rate to benralizumab (p = 0.02 and 0.01, respectively). Ischemic heart disease (IHD), bronchiectasis, and continued use of OCS increased the likelihood of poor response to omalizumab by 21, 7, and 24 times (p = 0.004, 0.008, and 0.004, respectively). In contrast, the female gender, childhood-onset asthma and higher BMI increased the likelihood of poor response to benralizumab by 7, 7 and 2 times more, p = 0.03, 0.02 and 0.05, respectively.

CONCLUSION

Poor response to omalizumab treatment was independently associated with ischemic heart disease (IHD), bronchiectasis, and a history of maintenance oral corticosteroid (mOCS) use. Conversely, poor response to benralizumab therapy was independently linked to female gender, childhood-onset asthma and higher body mass index (BMI).

Characterization and inhibition of inflammasome responses in severe and non-severe asthma

BACKGROUND

Increased airway NLRP3 inflammasome-mediated IL-1β responses may underpin severe neutrophilic asthma. However, whether increased inflammasome activation is unique to severe asthma, is a common feature of immune cells in all inflammatory types of severe asthma, and whether inflammasome activation can be therapeutically targeted in patients, remains unknown.

OBJECTIVE

To investigate the activation and inhibition of inflammasome-mediated IL-1β responses in immune cells from patients with asthma.

METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from patients with non-severe (n = 59) and severe (n = 36 stable, n = 17 exacerbating) asthma and healthy subjects (n = 39). PBMCs were stimulated with nigericin or lipopolysaccharide (LPS) alone, or in combination (LPS + nigericin), with or without the NLRP3 inhibitor MCC950, and the effects on IL-1β release were assessed.

RESULTS

PBMCs from patients with non-severe or severe asthma produced more IL-1β in response to nigericin than those from healthy subjects. PBMCs from patients with severe asthma released more IL-1β in response to LPS + nigericin than those from non-severe asthma. Inflammasome-induced IL-1β release from PBMCs from patients with severe asthma was not increased during exacerbation compared to when stable. Inflammasome-induced IL-1β release was not different between male and female, or obese and non-obese patients and correlated with eosinophil and neutrophil numbers in the airways. MCC950 effectively suppressed LPS-, nigericin-, and LPS + nigericin-induced IL-1β release from PBMCs from all groups.

CONCLUSION

An increased ability for inflammasome priming and/or activation is a common feature of systemic immune cells in both severe and non-severe asthma, highlighting inflammasome inhibition as a universal therapy for different subtypes of disease.

Age-related differences in associations between uncontrolled asthma, comorbidities and biomarkers in adult-onset asthma

OBJECTIVE

Adult-onset asthma is a recognized but heterogeneous phenotype and has been described to associate with poor asthma control. Knowledge about associations between clinical characteristics including comorbidities and control of adult-onset asthma is limited, especially in older populations. We aimed to study how clinical biomarkers and comorbidities are associated with uncontrolled asthma among middle-aged and older individuals with adult-onset asthma.

METHODS

Clinical examinations including structured interview, asthma control test (ACT), spirometry, skin prick test (SPT), blood sampling, and measurement of exhaled fractional nitric oxide (FeNO) was performed in a population-based adult-onset asthma cohort in 2019-2020 (n = 227, 66.5% female). Analyses were performed among all included, and separately in middle-aged (37-64 years, n = 120) and older (≥65 years, n = 107) participants.

RESULTS

In bivariate analysis, uncontrolled asthma (ACT ≤ 19) was significantly associated with a blood neutrophil count ≥5/µl, BMI ≥30, and several comorbidities. In multivariable regression analysis, uncontrolled asthma was associated with neutrophils ≥5/µl (OR 2.35; 95% CI 1.11-4.99). In age-stratified analysis, BMI ≥30 (OR 3.04; 1.24-7.50), eosinophils ≥0.3/µl (OR 3.17; 1.20-8.37), neutrophils ≥5/µl (OR 4.39; 1.53-12.62) and allergic rhinitis (OR 5.10; 1.59-16.30) were associated with uncontrolled asthma among the middle-aged. Among the older adults, uncontrolled asthma was only associated with comorbidities: chronic rhinitis (OR 4.08; 1.62-10.31), ischemic heart disease (OR 3.59; 1.17-10.98), malignancy (OR 3.10; 1.10-8.73), and depression/anxiety (OR 16.31; 1.82-146.05).

CONCLUSIONS

In adult-onset asthma, comorbidities were strongly associated with uncontrolled asthma among older adults, while clinical biomarkers including eosinophils and neutrophils in blood were associated with uncontrolled asthma among middle-aged.

Real-life studies and registries of severe asthma: The advent of digital technology

Severe asthma is a chronic and heterogeneous disease that negatively affects the quality of life of our patients and health care utilization. Given the remaining burden of uncontrolled disease in many of these patients, better understanding of its epidemiology, disease mechanisms, effectiveness of novel therapies such as biologics are still highly needed. Asthma treatment guidelines are largely informed by randomized controlled trials (RCTs) and meta analyses of RCTs, however inclusion criteria of many efficacy RCTs of asthma treatments often exclude a high number of patients with asthma in the community. Data from real-life studies and registries of severe asthma can complement efficacy studies by not only providing evidence on how a treatment performs in everyday clinical practice, post marketing safety information, data to support subsequent clinical trial design, but also helping to delineate the natural history of a disease and supporting important translational research endeavors. In the current review, we summarise available national and international collaborative studies and registries, the variables studies and the novel data and insights they provide. The key source of information for most asthma registries are real-life data from patient's electronic health records. Advent of digital technology in collecting data and their analysis is obvious and we draw attention to generation of new knowledge from registries of severe asthma to improve current diagnostic and therapeutic guidelines and asthma control.

Oxidized Phosphatidylcholines Trigger TRPA1 and Ryanodine Receptor-dependent Airway Smooth Muscle Contraction

Asthma pathobiology includes oxidative stress that modifies cell membranes and extracellular phospholipids. Oxidized phosphatidylcholines (OxPCs) in lung lavage from allergen-challenged human participants correlate with airway hyperresponsiveness and induce bronchial narrowing in murine thin-cut lung slices. OxPCs activate many signaling pathways, but mechanisms for these responses are unclear. We hypothesize that OxPCs stimulate intracellular free Ca2+ flux to trigger airway smooth muscle contraction. Intracellular Ca2+ flux was assessed in Fura-2-loaded, cultured human airway smooth muscle cells. Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (OxPAPC) induced an approximately threefold increase in 20 kD myosin light chain phosphorylation. This correlated with a rapid peak in intracellular cytoplasmic Ca2+ concentration ([Ca2+]i) (143 nM) and a sustained plateau that included slow oscillations in [Ca2+]i. Sustained [Ca2+]i elevation was ablated in Ca2+-free buffer and by TRPA1 inhibition. Conversely, OxPAPC-induced peak [Ca2+]i was unaffected in Ca2+-free buffer, by TRPA1 inhibition, or by inositol 1,4,5-triphosphate receptor inhibition. Peak [Ca2+]i was ablated by pharmacologic inhibition of ryanodine receptor (RyR) Ca2+ release from the sarcoplasmic reticulum. Inhibiting the upstream RyR activator cyclic adenosine diphosphate ribose with 8-bromo-cyclic adenosine diphosphate ribose was sufficient to abolish OxPAPC-induced cytoplasmic Ca2+ flux. OxPAPC induced ∼15% bronchial narrowing in thin-cut lung slices that could be prevented by pharmacologic inhibition of either TRPA1 or RyR, which similarly inhibited OxPC-induced myosin light chain phosphorylation in cultured human airway smooth muscle cells. In summary, OxPC mediates airway narrowing by triggering TRPA1 and RyR-mediated mobilization of intracellular and extracellular Ca2+ in airway smooth muscle. These data suggest that OxPC in the airways of allergen-challenged subjects and subjects with asthma may contribute to airway hyperresponsiveness.

Clinical remission in severe asthma with biologic therapy: an analysis from the UK Severe Asthma Registry

BACKGROUND

Novel biologic therapies have revolutionised the management of severe asthma with more ambitious treatment aims. Here we analyse the definition of clinical remission as a suggested treatment goal and consider the characteristics associated with clinical remission in a large, real-world severe asthma cohort.

METHODS

This was a retrospective analysis of severe asthma patients registered in the UK Severe Asthma Registry (UKSAR) who met strict national access criteria for biologics. Patients had a pre-biologics baseline assessment and annual review. The primary definition of clinical remission applied included Asthma Control Questionnaire (ACQ)-5 <1.5 and no oral corticosteroids for disease control and forced expiratory volume in 1 s above lower limit of normal or no more than 100 mL less than baseline.

RESULTS

18.3% of patients achieved the primary definition of remission. The adjusted odds of remission on biologic therapy were 7.44 (95% CI 1.73-31.95)-fold higher in patients with type 2 (T2)-high biomarkers. The adjusted odds of remission were lower in patients who were female (OR 0.61, 95% CI 0.45-0.93), obese (OR 0.49, 95% CI 0.24-0.65) or had ACQ-5 ≥1.5 (OR 0.19, 95% CI 0.12-0.31) pre-biologic therapy. The likelihood of remission reduced by 14% (95% CI 0.76-0.97) for every 10-year increase in disease duration. 12-21% of the cohort attained clinical remission depending on the definition applied; most of those who did not achieve remission failed to meet multiple criteria.

CONCLUSIONS

18.3% of patients achieved the primary definition of clinical remission. Remission was more likely in T2-high biomarker patients with shorter duration of disease and less comorbidity. Further research on the optimum time to commence biologics in severe asthma is required.

Tezepelumab: an anti-thymic stromal lymphopoietin monoclonal antibody for the treatment of asthma

Asthma is a common chronic respiratory disease in which epithelial cytokines and airway inflammation play critical pathophysiological roles. Thymic stromal lymphopoietin (TSLP), an epithelial cytokine, is central in the initiation and persistence of airway inflammation in asthma. Tezepelumab is a human immunoglobulin G2λ (IgG2λ) monoclonal antibody developed for treating moderate-to-severe asthma by specifically binding to TSLP and preventing its binding to the TSLP receptor on inflammatory cells. In this narrative review, we describe the results of clinical trials that evaluated the pharmacokinetics, pharmacodynamics, efficacy and safety of tezepelumab in patients with moderate-to-severe asthma. We also introduce the ongoing clinical trials in patients with asthma as well as future trials investigating the use of tezepelumab for other indications.

Inhaled RNA drugs to treat lung diseases: Disease-related cells and nano-bio interactions

In recent years, RNA-based therapies have gained much attention as biomedicines due to their remarkable therapeutic effects with high specificity and potency. Lung diseases offer a variety of currently undruggable but attractive targets that could potentially be treated with RNA drugs. Inhaled RNA drugs for the treatment of lung diseases, including asthma, chronic obstructive pulmonary disease, cystic fibrosis, and acute respiratory distress syndrome, have attracted more and more attention. A variety of novel nanoformulations have been designed and attempted for the delivery of RNA drugs to the lung via inhalation. However, the delivery of RNA drugs via inhalation poses several challenges. It includes protection of the stability of RNA molecules, overcoming biological barriers such as mucus and cell membrane to the delivery of RNA molecules to the targeted cytoplasm, escaping endosomal entrapment, and circumventing unwanted immune response etc. To address these challenges, ongoing researches focus on developing innovative nanoparticles to enhance the stability of RNA molecules, improve cellular targeting, enhance cellular uptake and endosomal escape to achieve precise delivery of RNA drugs to the intended lung cells while avoiding unwanted nano-bio interactions and off-target effects. The present review first addresses the pathologic hallmarks of different lung diseases, disease-related cell types in the lung, and promising therapeutic targets in these lung cells. Subsequently we highlight the importance of the nano-bio interactions in the lung that need to be addressed to realize disease-related cell-specific delivery of inhaled RNA drugs. This is followed by a review on the physical and chemical characteristics of inhaled nanoformulations that influence the nano-bio interactions with a focus on surface functionalization. Finally, the challenges in the development of inhaled nanomedicines and some key aspects that need to be considered in the development of future inhaled RNA drugs are discussed.

The association of varying treatment thresholds of mepolizumab on asthma exacerbations in adults

Background: Asthma has a high healthcare burden globally, with up to 10% of the asthma population suffering from severe disease. Biologic agents are a newer class of asthma treatments for severe asthma, with good evidence for efficacy in clinical trials. Nevertheless, real-world studies of its impact on clinical outcomes are limited.Methods: This is an observational cohort study using administrative claims data. The study population consisted of patients aged ≥18 years who had a diagnosis of asthma and initiated mepolizumab after November 4, 2015 and had continuous medical and drug coverage in both the 365 days prior to and following mepolizumab initiation. In patients treated with mepolizumab, we described clinically significant asthma exacerbations by minimum continuous treatment thresholds following initiation of mepolizumab, medication switching patterns and chronic oral corticosteroid (≥28 days) use.Results: We identified 2,536 adults with asthma who initiated mepolizumab. There was an association toward reduction in severe asthma-related events over the first one year of exposure. We observed associations with reduced dispensings of oral corticosteroids over the first year after mepolizumab initiation. Very few patients switched to other biologics during the study period.Conclusions: Treatment with mepolizumab may be associated with fewer asthma-related events in the first year. Over the first one year after initiating mepolizumab, we found associations with decreased concomitant dispensings of oral corticosteroids and medium to high dose ICS/LABA. Additionally, most patients who initiated mepolizumab did not switch to other biologics.

Mepolizumab in Patients With Severe Asthma and Comorbidities: 1-Year REALITI-A Analysis

BACKGROUND

Severe asthma is complex; comorbidities may influence disease outcomes.

OBJECTIVE

To assess mepolizumab effectiveness in patients with severe asthma and comorbidities.

METHODS

REALITI-A was a 2-year international, prospective study enrolling adults with asthma newly prescribed mepolizumab (100 mg subcutaneously) at physician's discretion. This post hoc analysis assessed 1-year outcomes stratified by comorbidities at enrollment: chronic rhinosinusitis with nasal polyps (CRSwNP), gastroesophageal reflux disease (GERD), depression/anxiety, and chronic obstructive pulmonary disease (COPD). Outcomes included the rate of clinically significant asthma exacerbations (CSEs; requiring systemic corticosteroids and/or hospital/emergency room admission) between the 12 months pre- and post-mepolizumab treatment and changes from baseline in daily maintenance oral corticosteroid dose (mo 12), Asthma Control Questionnaire-5 score (mo 12) and forced expiratory volume in 1 second (FEV1; mo 9-12).

RESULTS

At enrollment (n = 822), 321 of 822 (39%), 309 of 801 (39%), 203 of 785 (26%), and 81 of 808 (10%) patients had comorbid CRSwNP, GERD, depression/anxiety, and COPD, respectively. Post- versus pre-treatment across all comorbidity subgroups: the rate of CSEs decreased by 63% or more; among 298 (39%) patients on maintenance oral corticosteroids at baseline, median dose decreased by 50% or more; Asthma Control Questionnaire-5 score decreased by 0.63 or more points; FEV1 increased by 74 mL or more. Patients with versus without CRSwNP had the greatest improvements (eg, rate of CSEs decreased by 75%). Patients without GERD, depression/anxiety, or COPD had greater improvements than those with the respective comorbidities, except for FEV1 in patients with COPD.

CONCLUSIONS

Mepolizumab improved disease outcomes in patients with severe asthma irrespective of comorbidities, with additional benefit for patients with CRSwNP.

Biologics for severe asthma and beyond

Advances in pathophysiological understanding and the elucidation of a type 2 inflammatory signature with interleukins 4, 5 and 13 at its center have led to the development of targeted antibody therapies that are now approved for the treatment of severe asthma. In suitable patients, these medications reduce asthma exacerbations and the necessity for oral corticosteroids, improve asthma control, quality of life and lung function. A proportion of patients with severe asthma may even achieve remission under ongoing biologic therapy. Type-2 inflammatory comorbidities are frequent in patients with severe asthma, sharing overlapping pathophysiology and may similarly respond to biologic treatment. Here, we give an overview of the six biologic therapies currently approved for severe asthma and review randomized clinical trials and real-life studies in asthma and other type-2 inflammatory diseases. We also discuss selection of biologics according to licensing criteria, asthma phenotype and biomarkers, monitoring of treatment response and proceedings in case of insufficient outcome under therapy.

Brittle Asthma: Still on Board?

(1) Background: "Brittle Asthma" was considered an asthma clinical phenotype and deemed to be life-threatening in the early 2000s; then, this definition disappeared. The purpose of this review is to examine what has historically been referred to as this term and see whether it may be applied to modern clinical practice, thus acquiring fresh relevance and meaning. (2) Methods: A non-systematic search of the literature was conducted using both MeSH and free-text phrases. No limitations on the research design or type of publication were applied. (3) Results: Reliable data regarding "Brittle Asthma" are lacking due to the paucity of current data and the few studies available. After a few years of reworking, it was divided into two sub-classes: one characterized by a wide PEF variability despite high-dose therapy and the other by sudden acute attacks in otherwise apparently normal airway functions or well-controlled asthma. Their characteristics were hardly defined because of their low prevalence. Data regarding risk factors, atopy, mechanisms, and treatments were analyzed. (4) Conclusions: Over time, different terminology has been introduced to define asthma severity and control. It would be worth investigating whether the term "Brittle Asthma" previously used may be helpful to find new hints to stratify patients and improve disease management.

Combination of Biological Therapy in Severe Asthma: Where We Are?

Biological drugs have revolutionized the management of severe asthma. However, a variable number of patients remain uncontrolled or only partially controlled even after the appropriate administration of a biologic agent. The combination of two biologics may target different inflammatory pathways, and it has been used in patients suffering from uncontrolled severe asthma with evidence of both allergic and eosinophilic phenotypes or severe asthma and type2 comorbidities. Combination therapy has also been used to handle anti-IL4/13R induced hypereosinophilia. There is insufficient data on combining biologics for the treatment of severe uncontrolled asthma and type 2 comorbidities, also because of the high cost, and currently no guideline recommends dual biologic therapy. A systematic search was performed using the Medline and Scopus databases. Published data on concurrent administration of two biological drugs in severe, uncontrolled asthma patients has been reported in 28 real-world studies and 1 clinical trial. Data extraction was followed by a descriptive and narrative synthesis of the findings. Future studies should be conducted to further assess the safety, efficacy, and cost-effectiveness of this therapeutic strategy.

Real-world severe asthma biologic administration and adherence differs by biologic: CHRONICLE study results

BACKGROUND

Patient adherence to biologic therapies is crucial for clinical benefits. Previous assessments of US patient adherence to severe asthma (SA) biologic therapies have relied on health care insurance claims data that have limitations.

OBJECTIVE

To describe real-world, specialist-reported, biologic administration and adherence among US adults with SA.

METHODS

CHRONICLE (ClinicalTrials.gov identifier: NCT03373045) is an ongoing real-world, noninterventional study of patients with SA treated by US subspecialists. Sites report date and location for all biologic administrations. We evaluated biologic (benralizumab, dupilumab, mepolizumab, omalizumab, reslizumab) adherence as the proportion of days covered (PDC) during the first 52 weeks and the mean number of days until patients received the expected number of doses for 13, 26, and 52 weeks of treatment.

RESULTS

A total of 2117 patients received biologic administrations between February 2018 and February 2022. Most patients (84%) received biologic administrations at a subspecialist site. Over time, administrations at specialist sites decreased, whereas at-home administrations increased. The median PDC was 87%; the mean number of days to receive a 52-week (364-day) equivalent number of doses was 423 for all biologics (average delay of 58 days). Dupilumab had the lowest PDC and highest mean delays in dosing across all intervals; better adherence was observed among commercially insured patients.

CONCLUSION

Patients with SA are mostly adherent to biologic therapies. Biologics with shorter dosing intervals and at-home administration had worse adherence, likely because of greater opportunities for delays. Specialist-reported administration data provide a unique perspective on biologic adherence, which may be overestimated for at-home administrations by insurance claims data.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT03373045.

Expert Consensus on SABA Use for Asthma Clinical Decision-Making: A Delphi Approach

PURPOSE OF REVIEW

A modified Delphi process was undertaken to provide a US expert-led consensus to guide clinical action on short-acting beta2-agonist (SABA) use. This comprised an online survey (Phase 1), forum discussion and statement development (Phase 2), and statement adjudication (Phase 3).

RECENT FINDINGS

In Phase 1 (n = 100 clinicians), 12% routinely provided patients with ≥4 SABA prescriptions/year, 73% solicited SABA use frequency at every patient visit, and 21% did not consult asthma guidelines/expert reports. Phase 3 experts (n = 8) reached consensus (median Likert score, interquartile range) that use of ≥3 SABA canisters/year is associated with increased risk of exacerbation and asthma-related death (5, 4.75-5); SABA use history should be solicited at every patient visit (5, 4.75-5); usage patterns over time, not absolute thresholds, should guide response to SABA overuse (5, 4.5-5). Future asthma guidelines should include clear recommendations regarding SABA usage, using expert-led thresholds for action.

COVID-19 and Its Impact on Common Diseases in the Allergy Clinics

Coronavirus disease 2019 (COVID-19) is a highly contagious viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has various effects on asthma, allergic rhinitis, atopic dermatitis, and urticaria and may change the course of the disease depending on the severity of the infection and control status of the disease. Conversely, these diseases may also impact the course of COVID-19. Patients with chronic urticaria and atopic dermatitis may have COVID-19-induced disease exacerbations and biological treatments reduce the risk of exacerbations. Poor asthma control is linked to severe COVID-19 while allergic asthma is associated with lower risk of death and a lower rate of hospitalization due to COVID-19 compared with nonallergic asthma. The use of intranasal corticosteroids is associated with lower rates of hospitalization due to COVID-19 in patients with allergic rhinitis, whereas the effect of inhaled corticosteroids is confounded by asthma severity. These observations reinforce the importance of keeping allergic diseases under control during pandemics. The use of biologicals during COVID-19 is generally regarded as safe, but more evidence is needed. The pandemic substantially changed the management of allergic disorders such as home implementation of various biologicals, allergen immunotherapy, food introduction, and increased use of telemedicine and even home management of anaphylaxis to reduce emergency department burden and reduce risk of infection. Physicians need to be aware of the potential impact of COVID-19 on allergic diseases and educate their patients on the importance of continuing prescribed medications and adhering to their treatment plans to maintain optimal control of their disease.

Standardization of clinical outcomes used in allergen immunotherapy in allergic asthma: An EAACI position paper

INTRODUCTION

In allergic asthma patients, one of the more common phenotypes might benefit from allergen immunotherapy (AIT) as add-on intervention to pharmacological treatment. AIT is a treatment with disease-modifying modalities, the evidence for efficacy is based on controlled clinical trials following standardized endpoint measures. However, so far there is a lack of a consensus for asthma endpoints in AIT trials. The aim of a task force (TF) of the European Academy of Allergy and Clinical Immunology (EAACI) is evaluating several outcome measures for AIT in allergic asthma.

METHODS

The following domains of outcome measures in asthmatic patients have been evaluated for this position paper (PP): (i) exacerbation rate, (ii) lung function, (iii) ICS withdrawal, (iv) symptoms and rescue medication use, (v) questionnaires (PROMS), (vi) bronchial/nasal provocation, (vii) allergen exposure chambers (AEC) and (viii) biomarkers.

RESULTS

Exacerbation rate can be used as a reliable objective primary outcome; however, there is limited evidence due to different definitions of exacerbation. The time after ICS withdrawal to first exacerbation is considered a primary outcome measure. Besides, the advantages and disadvantages and clinical implications of further domains of asthma endpoints in AIT trials are elaborated in this PP.

CONCLUSION

This EAACI-PP aims to highlight important aspects of current asthma measures by critically evaluating their applicability for controlled trials of AIT.

Allergy to fungi: Advances in the understanding of fungal allergens

Allergic diseases are a major health problem due to their increasing incidence and high prevalence worldwide. Asthma has several aetiologies, and allergy plays an important role in its development in approximately 60% of adults and 80% of children and adolescents. Although the link between aeroallergen sensitization and asthma exacerbations has been long recognized, the investigations of the triggering allergens may be superficial in many asthma cases. The main allergenic sources related to asthma, and other allergic diseases, are pollens, mites, fungi, and animal epithelia. Fungi are considered the third most frequent cause of respiratory pathologies. Asthma caused by several fungi species may have a bad prognosis in some cases due to its severity and difficulty in avoidance methods. Despite the recognised relevance of fungi in respiratory allergies, the knowledge about fungal allergens seems to be scarce, with few descriptions of new allergens, compared to other allergenic sources. The study of major, minor, and cross-reactive fungal allergens, and their relevance in the allergic disease, might be crucial, not only to accurately diagnose these allergies, but also to predict exacerbations and responses to therapies, as well as for the development of personalized treatment plans in a fast-changing climate scenario.

TAT decorated siRNA polyplexes for inhalation delivery in anti-asthma therapy

In this work, a novel protonable copolymer was designed to deliver siRNA through the inhalation route, as an innovative formulation for the management of asthma. This polycation was synthesized by derivatization of α,β-poly(N-2-hydroxyethyl)D,L-aspartamide (PHEA) first with 1,2-Bis(3-aminopropylamino)ethane (bAPAE) and then with a proper amount of maleimide terminated poly(ethylene glycol) (PEG-MLB), with the aim to increase the superficial hydrophilicity of the system, allowing the diffusion trough the mucus layer. Once the complexation ability of the copolymer has been evaluated, obtaining nanosized polyplexes, polyplexes were functionalized on the surface with a thiolated TAT peptide, a cell-penetrating peptide (CPP), exploiting a thiol-ene reaction. TAT decorated polyplexes result to be highly cytocompatible and able to retain the siRNA with a suitable complexation weight ratio during the diffusion process through the mucus. Despite polyplexes establish weak bonds with the mucin chains, these can diffuse efficiently through the mucin layer and therefore potentially able to reach the bronchial epithelium. Furthermore, through cellular uptake studies, it was possible to observe how the obtained polyplexes penetrate effectively in the cytoplasm of bronchial epithelial cells, where they can reduce IL-8 gene expression, after LPS exposure. In the end, in order to obtain a formulation administrable as an inhalable dry powder, polyplexes were encapsulated in mannitol-based microparticles, by spray freeze drying, obtaining highly porous particles with proper technological characteristics that make them potentially administrable by inhalation route.

Dupilumab sustains efficacy in patients with moderate-to-severe type 2 asthma regardless of inhaled corticosteroids dose

BACKGROUND

Dupilumab, a human monoclonal antibody, blocks the shared receptor component for interleukins-4/13, key and central drivers of type 2 inflammation. The TRAVERSE (NCT02134028) open-label extension study demonstrated the long-term safety and efficacy of dupilumab in patients ≥12 years who completed a previous dupilumab asthma study. The safety profile was consistent with that observed in the parent studies. Here, we assess whether dupilumab sustains long-term efficacy in patients regardless of inhaled corticosteroid (ICS) dose at parent study baseline (PSBL).

METHODS

Patients from phase 2b (NCT01854047) or phase 3 (QUEST; NCT02414854) studies receiving high- or medium-dose ICS at PSBL and enrolled in TRAVERSE were included. We analyzed unadjusted annualized severe exacerbation rates, change from PSBL in pre-bronchodilator (BD) forced expiratory volume in 1 second (FEV1 ), 5-item asthma control questionnaire, and type 2 biomarkers in patients with type 2 asthma at baseline (blood eosinophils ≥150 cells/μL or fractional exhaled nitric oxide [FeNO] ≥25 ppb), and subgroups defined by baseline blood eosinophils or FeNO.

RESULTS

Of patients with type 2 asthma (n = 1666), 891 (53.5%) were receiving high-dose ICS at PSBL. In this subgroup, unadjusted exacerbation rates for dupilumab versus placebo were 0.517 versus 1.883 (phase 2b) and 0.571 versus 1.300 (QUEST) over the parent study (52 weeks) and remained low throughout TRAVERSE (0.313-0.494). Improvements in pre-BD FEV1 were sustained throughout TRAVERSE. Similar clinical efficacy was observed among patients receiving medium-dose ICS at PSBL and biomarker subgroups.

CONCLUSIONS

Dupilumab showed sustained efficacy for up to 3 years in patients with uncontrolled, moderate-to-severe type 2 asthma on high- or medium-dose ICS.

A robust mRNA signature obtained via recursive ensemble feature selection predicts the responsiveness of omalizumab in moderate-to-severe asthma

BACKGROUND

Not being well controlled by therapy with inhaled corticosteroids and long-acting β2 agonist bronchodilators is a major concern for severe-asthma patients. The current treatment option for these patients is the use of biologicals such as anti-IgE treatment, omalizumab, as an add-on therapy. Despite the accepted use of omalizumab, patients do not always benefit from it. Therefore, there is a need to identify reliable biomarkers as predictors of omalizumab response.

METHODS

Two novel computational algorithms, machine-learning based Recursive Ensemble Feature Selection (REFS) and rule-based algorithm Logic Explainable Networks (LEN), were used on open accessible mRNA expression data from moderate-to-severe asthma patients to identify genes as predictors of omalizumab response.

RESULTS

With REFS, the number of features was reduced from 28,402 genes to 5 genes while obtaining a cross-validated accuracy of 0.975. The 5 responsiveness predictive genes encode the following proteins: Coiled-coil domain- containing protein 113 (CCDC113), Solute Carrier Family 26 Member 8 (SLC26A), Protein Phosphatase 1 Regulatory Subunit 3D (PPP1R3D), C-Type lectin Domain Family 4 member C (CLEC4C) and LOC100131780 (not annotated). The LEN algorithm found 4 identical genes with REFS: CCDC113, SLC26A8 PPP1R3D and LOC100131780. Literature research showed that the 4 identified responsiveness predicting genes are associated with mucosal immunity, cell metabolism, and airway remodeling.

CONCLUSION AND CLINICAL RELEVANCE

Both computational methods show 4 identical genes as predictors of omalizumab response in moderate-to-severe asthma patients. The obtained high accuracy indicates that our approach has potential in clinical settings. Future studies in relevant cohort data should validate our computational approach.

Tezepelumab reduces exacerbations across all seasons in patients with severe, uncontrolled asthma (NAVIGATOR)

BACKGROUND

Asthma exacerbation frequencies vary throughout the year owing to seasonal triggers. Tezepelumab is a human monoclonal antibody that targets thymic stromal lymphopoietin. In the phase 3 NAVIGATOR study (NCT03347279), tezepelumab significantly reduced the annualized asthma exacerbation rate (AAER) vs placebo in patients with severe, uncontrolled asthma.

OBJECTIVE

To evaluate the effect of tezepelumab on asthma exacerbations across all seasons in NAVIGATOR patients (post hoc).

METHODS

NAVIGATOR was a multicenter, randomized, double-blind, placebo-controlled study. Patients (12-80 years old) were randomized 1:1 to tezepelumab 210 mg or placebo subcutaneously every 4 weeks for 52 weeks. AAER over 52 weeks was assessed by season. Data from patients in the Southern Hemisphere were transformed to align with Northern Hemisphere seasons.

RESULTS

Tezepelumab reduced the AAER vs placebo by 63% (95% confidence interval [CI], 52-72) in winter, 46% (95% CI, 26-61) in spring, 62% (95% CI, 48-73) in summer, and 54% (95% CI, 41-64) in fall. In matched climates, during the spring allergy season (March 1 to June 15) and ragweed allergy season (September), tezepelumab reduced the AAER vs placebo in patients with seasonal allergy by 59% (95% CI, 29-77) and 70% (95% CI, 33-87), respectively. In patients with perennial allergy and in those with seasonal allergy, tezepelumab reduced the AAER vs placebo across all seasons.

CONCLUSION

Tezepelumab reduced exacerbations across all seasons vs placebo in patients with severe, uncontrolled asthma, including patients with seasonal and perennial allergies. These data further support the efficacy of tezepelumab in a broad population of patients with severe, uncontrolled asthma.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03347279 (https://clinicaltrials.gov/ct2/show/NCT03347279).

Hyperventilation syndrome in children with asthma

BACKGROUND

Hyperventilation syndrome (HVS) may be associated with asthma. In the absence of a gold standard diagnosis for children, its impact on asthma has been rarely assessed.

OBJECTIVE

To assess the impact of HVS on the symptoms and lung function of children with asthma and determine the diagnostic value of the Nijmegen questionnaire in comparison to a hyperventilation test (HVT).

METHODS

Data from asthmatic children followed in the department of Pediatric Pulmonology of Necker Hospital and explored for HVS were retrospectively analyzed. HVS was diagnosed by a positive HVT. Asthma exacerbations, control and lung function were assessed in children with or without a positive HVT. The sensitivity and specificity of the Nijmegen questionnaire were determined relative to the positivity of a HVT. The Nijmegen questionnaire threshold was ≥23.

RESULTS

Data from 112 asthmatic children, median age 13.9 years [11.6-16], were analyzed. Twenty-eight children (25%) had mild or moderate asthma and 84 (75%) severe asthma. The HVT was performed on 108 children and was negative for 34 (31.5%) and positive for 74 (68.5%). The number of asthma exacerbations in the past 12 months, Asthma Control Test (ACT) score, and lung function did not differ between children with a positive HVT and a negative HVT. The Nijmegen questionnaire was administered to 103 children. Its sensitivity was 56.3% and specificity 56.3%.

CONCLUSION

The symptoms and lung function of adolescents with asthma are not affected by the presence of HVS. The sensitivity and specificity of the Nijmegen questionnaire are low.

Patterns of allergic sensitization in adults with severe asthma: the ATLAS non-interventional study

OBJECTIVES

Severe asthma is heterogeneous, with childhood-onset asthma believed more likely to be allergic, whereas adult-onset asthma is considered typically non-allergic. However, the allergic diagnosis is typically by exclusion: if patients do not react to an allergen panel, which is not standardized and often limited to few allergens, they are considered non-allergic. The overall aim of the ATLAS study was to characterize the sensitization to allergens in severe asthma (independent of phenotype).

METHODS

Single-visit, cross-sectional, non-interventional study in adults with severe asthma. Analyses were conducted for total and specific immunoglobulin E against 53 allergens, overall and in subgroups, including age at asthma onset (<20 [childhood-onset] and >40 years of age).

RESULTS

Among 1010 recruited patients, 28.4% reported childhood-onset asthma and 33.6% onset >40 years of age. After excluding patients receiving omalizumab/anti-IL5 therapy, 27.6% were not sensitized to any tested allergens, whereas 19.1% were sensitized to >10 allergens. All allergens triggered sensitization in some patients. Baseline characteristics in the two onset subgroups were similar; 23.2% with childhood-onset asthma were not sensitized to any allergen, compared to 32.0% with onset >40 years of age.

CONCLUSION

When a broad panel of allergens is used for sensitization testing, as many as three quarters of patients with severe asthma display sensitivity to at least one allergen, with substantial overlaps in all characteristics between the two age-at-onset subgroups. All of the tested allergens triggered a response in at least some patients, emphasizing the importance of including a broad range of allergens in any testing panel.

The perceived waning of biologics in severe asthma

BACKGROUND

Biologics are highly effective in severe asthma and used at fixed dosing intervals. However, in clinical practice, dosing intervals are sometimes shortened if patients perceive a decreased biologic effect before the next administration. The occurrence and clinical relevance of this perceived waning of biological effect is unknown.

OBJECTIVE

To explore (1) the frequency, severity and conditions, (2) associated symptoms and (3) relationship with clinical characteristics of the patient-perceived waning effect of biologics before the next administration.

METHODS

Severe asthma patients receiving biological treatment ≥4 months were included. Based on 17 semi-structured patient interviews, we developed a questionnaire focusing on the waning effect of biologics before the next administration, which was distributed among 129 patients. Clinical characteristics, including asthma control (ACQ) and quality of life (AQLQ) scores, were collected from patient files.

RESULTS

65/101 patients who completed the questionnaire reported a waning of biological effect, graded as severe (median (IQR) 6.5 (5-7.5) on a 0-10 BORG-scale). Waning manifested in a broad spectrum of symptoms. Patients reporting waning had higher ACQ and lower AQLQ scores versus those without (p < 0.05) and higher BORG-scores were associated with higher exacerbation rate (ρ = 0.309, p = 0.013). A third of all patients were in favor of extending or shortening their dosing interval.

CONCLUSION

Two-thirds of severe asthma patients report waning of biologic effect at the end of the dosing interval, which is associated with poorer asthma control and quality of life. The diversity in observed waning of effect opens the way for research into more individualized dosing of biologics.

Characterization of Obesity in Severe Asthma in the German Asthma Net

BACKGROUND

Asthma is increasingly recognized as heterogeneous, characterized by different endotypes, with obesity not only a distinct phenotype but a risk factor for severe asthma.

OBJECTIVE

We sought to understand the associations of obesity with relevant parameters of severe asthma, including asthma control, disease burden, and lung function.

METHODS

The German Asthma Net registry is a multicenter international real-life registry capturing long-term follow-up data. This analysis included 2213 patients (52 ± 16 years, 58% female, 29% with obesity [body mass index ≥30 kg/m2], 4.2 ± 4.3 exacerbations/year). The primary analysis assessed relationships between BMI and variables through univariate tests, followed by a multiple regression model. Secondary outcomes regarded clinically relevant variables in relation to weight groups.

RESULTS

Patients with obesity were more frequently female, more likely to have depression and gastroesophageal reflux, and suffered from worse asthma control, lower quality of life, reduced static lung volumes, more pronounced hypoxemia, and higher blood neutrophil counts, all statistically significant. Blood eosinophils, exhaled nitric oxide, and total IgE were independent of obesity. In the multiple regression analysis, obesity was significantly associated with more frequent reflux and depression, reduced static lung function values, older age, poor asthma control, and long-acting muscarinic antagonist therapy, and inversely associated with bronchiectasis and nonsmoking status.

CONCLUSION

In this large, well-characterized cohort, we identified the association of obesity with a significantly higher disease burden and a similar portfolio of inflammation type 2 markers in patients with and without obesity; therefore, patients with obesity seem similarly eligible for the treatment with biologics targeting these disease endotypes.

Development and Dynamic Responsiveness of the Acute Asthma Exacerbation Survey in Patients With Moderate to Severe Disease

BACKGROUND

The recall periods and response scales of existing surveys of asthma control are poorly suited for studying acute exacerbations.

OBJECTIVE

To develop an instrument able to predict exacerbations after the onset of acute symptoms and with a recall window sufficiently short to study recovery.

METHODS

We developed the six-item Acute Asthma Exacerbation Survey (AAES). Data were collected at baseline, acute, and recovery visits within an established longitudinal protocol for participants with severe asthma. Participants scheduled acute study visits at the first sign of a cold. Nasal lavage samples and lung function measurements were also collected. The AAES data were analyzed using Cronbach α, Spearman correlations, and Kruskal-Wallace methods. We used logistic regression for predictors of bursts of oral corticosteroids (OCS).

RESULTS

Of 130 participants studied at baseline, 52 returned for an acute visit. The AAES scores were elevated at the acute visit and returned to baseline after recovery independently of respiratory virus detection. Cronbach α for the AAES was 0.853, 0.822, and 0.889 at the three respective visits. Compared with participants not needing burst OCS, those with exacerbations had higher acute AAES scores (16 [13.5-18] vs 11.5 [8.2-14], median [interquartile range]; P = .017) and a larger reduction from baseline in lung function. For each 3-point increase in AAES scores, the odds ratio for burst OCS use was 1.64 (95% CI, 1.04-2.57; P = .030).

CONCLUSIONS

The AAES is internally consistent and dynamically responsive during acute asthma exacerbations. Additional validation studies are warranted to support future trials and aid in clinical decision-making.

A cost comparison of benralizumab, mepolizumab, and dupilumab in patients with severe asthma: A US third-party payer perspective

BACKGROUND: Clinical trials and real-world evidence (RWE) studies of biologics have demonstrated reduced exacerbations, decreased use of oral corticosteroids (OCS), and improvements in daily symptoms and health-related quality of life in patients with severe eosinophilic asthma (SEA). OBJECTIVE: To compare direct health care costs associated with biologic use for the treatment of SEA from a US third-party payer perspective. METHODS: We developed a cost-minimization model to compare costs and cost offsets associated with 3 biologics-benralizumab, mepolizumab, and dupilumab-for 2- and 4-year periods. The model relied on longitudinal data from clinical trials to inform the primary (base case) analysis cost comparison and RWE study data, in a separate scenario, to compare costs in nonclinical trial settings. Primary model outcomes included exacerbations (including hospitalizations), OCS-dependent years (including associated complications), and total direct health care biologic costs. Results were calculated at the per patient and population level (per 1,000 patients). Sensitivity analyses with key model parameters were performed. RESULTS: Benralizumab had the lowest total biologic costs per patient for both the 2- and 4-year periods. Over 4 years, the marginal cost difference in total biologic costs per patient was $23,061 lower for benralizumab vs mepolizumab and $17,242 lower for benralizumab vs dupilumab. The 4-year population level analysis of benralizumab vs mepolizumab revealed $4.8 million in marginal cost offsets due to 582 fewer exacerbations and 153 fewer OCS-dependent years and a marginal total cost savings of $27.9 million per 1,000 patients for benralizumab. The 4-year population level analysis of benralizumab vs dupilumab revealed $2.3 million in marginal cost offsets due to 291 fewer exacerbations and 64 fewer OCS-dependent years and marginal total cost savings of $19.5 million per 1,000 patients for benralizumab. RWE data were available for a 2-year cost comparison scenario of benralizumab vs mepolizumab, which showed similar results to the base case analysis. Sensitivity analyses varying assumptions on key model parameter estimates confirmed results, with benralizumab having lower total direct health care costs in all scenarios tested, and showed that model results were most sensitive to changes in biologic costs and exacerbation reduction rates. CONCLUSIONS: Patients receiving benralizumab had higher nonbiologic cost offsets because of reductions in exacerbations and OCS-dependent years, leading to greater cost savings for third-party payers compared with patients receiving mepolizumab or dupilumab. Taken together with biologic costs, benralizumab presents greater savings in health care costs for payers than patients with SEA who use mepolizumab or dupilumab. DISCLOSURES: This study was funded by AstraZeneca (Cambridge, UK). Drs Xu, Chung, Genofre, and Katial are or were AstraZeneca employees at the time this research was conducted and may be shareholders of AstraZeneca. Ms Schaefer and Dr Szende are employees of Labcorp Drug Development, which received funding from AstraZeneca to perform this research.

Characterization of Austrian severe asthma patients

INTRODUCTION

The Severe Asthma Registry, founded by German Asthma Net (GAN) in 2011, is a prospective registry recording clinical parameters from participating centers in Germany, Austria and Switzerland. This article presents the baseline characteristics of severe asthma patients from Austrian centers.

METHODS

We analyzed the baseline visit data of all patients recruited to the GAN Severe Asthma Registry from participating Austrian centers.

RESULTS

Baseline visit data were available for 214 Austrian severe asthma patients from 6 Austrian centers from 2013 to 2022. Mean age was 53.7 years. Mean BMI was 26.4 kg/m2. More than a third (37.4%) of all patients had daily daytime asthma symptoms at baseline and had to use their reliever medication at least once per day. Forty-one percent of patients were classified as uncontrolled according to GINA and 24.8% as partially controlled at baseline visit. The median annual exacerbation frequency was 3 in the previous 12 months. At the time of baseline visit, 23.4% of all patients had regular treatment with oral corticosteroids. Furthermore, 23.9% had received any severe asthma monoclonal antibody prior to the baseline visit. There were no notable differences in baseline characteristics between patients categorized by smoking history or measurable type 2 inflammation.

CONCLUSIONS

This study provides the first multi-center characterization of Austrian severe asthma patients. Patients in this cohort had better asthma control and less frequent exacerbations compared to most international registries.

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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Benralizumab in severe eosinophilic asthma in real life: confirmed effectiveness and contrasted effect on sputum eosinophilia versus exhaled nitric oxide fraction - PROMISE

Background

Randomised controlled trials have shown that benralizumab, an anti-interleukin-5 receptor monoclonal antibody, reduces exacerbations and oral corticosteroid dose and improves asthma control and lung function in severe eosinophilic asthma. The aim of this study was to confirm results of randomised controlled trials in real life in a population of 73 patients with severe eosinophilic asthma treated with benralizumab for at least 12 months.

Methods

Patients underwent careful monitoring of asthma exacerbations, exhaled nitric oxide fraction, lung function, asthma control and quality of life questionnaire responses and sputum induction, and gave a blood sample at baseline, after 6 months and then every year.

Results

We found significant reductions in exacerbations (by 92%, p<0.0001) and oral corticosteroid dose (by 83%, p<0.001) after 6 months that were maintained over time, with 78% of patients able to stop oral corticosteroid therapy. Patients improved their Asthma Control Test (ACT) score (from 11.7±5.1 to 16.9±5.35, p<0.0001), Asthma Control Questionnaire (ACQ) score (from 2.88±1.26 to 1.77±1.32, p<0.0001) and Asthma Quality of Life Questionnaire score (+1.04, p<0.0001) at 6 months and this was maintained during follow-up. Only 35% and 43% of patients reached asthma control according to an ACT score ≥20 and ACQ score <1.5, respectively. We observed stable post-bronchodilation lung function over time and a significant reduction in sputum eosinophil count, with 85% of patients exhibiting sputum eosinophil counts <3% after 6 months (p<0.01) with no effect on exhaled nitric oxide fraction.

Conclusion

In our real-life study, we confirm the results published in randomised controlled trials showing a sharp reduction in exacerbations and oral corticosteroid therapy, an improvement in asthma control and quality of life, and a dramatic reduction in sputum eosinophil count.

Real-world super-response to biologics in severe asthma: A French monocentric retrospective cohort study

BACKGROUND

Biologics have dramatically improved outcomes in severe T2-high asthma. Although the identification of patients with the best response is key to understand the efficacy of these agents and select the best target populations, the definition and predictors of super-response are not fully established yet.

METHODS

This study aimed to describe super-response and to identify predictors of super-response to biologics in a French severe eosinophilic asthma cohort followed in a severe asthma tertiary care center between January 2005 and December 2020. Super-response was defined a priori as no oral corticosteroids intake and no exacerbations over 12 months. Collected data at baseline and after 12 months included asthma history, comorbidities, clinical characteristics, lung function, T2-biomarkers, baseline asthma-related treatments, and asthma control.

RESULTS

Among 157 patients assessed for eligibility, 108 were included, corresponding to 166 treatments with biologics. Overall response rate was 63.2 % (105/166) and super-response rate was 39.7 % (66/166). In omalizumab group (n = 67), lower dose of oral corticosteroids in maintenance was the only factor associated with super-response (p = 0.008). In the anti-IL-5/anti-IL-5R group (n = 99), absence or lower dose of oral corticosteroids in maintenance and absence of eosinophilic granulomatosis with polyangiitis were statistically associated with super-response (p = 0.009, p = 0.001 and p = 0.02 respectively).

CONCLUSION

In this real-life study in severe T2-high asthma patients, a lower dose or absence of daily oral corticosteroids and absence of eosinophilic granulomatosis with polyangiitis were the only identifiable predictors of super-response to biologics. Physicians should not wait for maintenance oral corticosteroids to be required before considering the initiation of a biologic in severe asthma.

Safety and Efficacy of Dexpramipexole in Eosinophilic Asthma (EXHALE): A randomized controlled trial

BACKGROUND

There is a need for new and effective oral asthma therapies. Dexpramipexole, an oral eosinophil-lowering drug, has not previously been studied in asthma.

OBJECTIVE

We sought to evaluate the safety and efficacy of dexpramipexole in lowering blood and airway eosinophilia in subjects with eosinophilic asthma.

METHODS

We performed a randomized, double-blind, placebo-controlled proof-of-concept trial in adults with inadequately controlled moderate to severe asthma and blood absolute eosinophil count (AEC) greater than or equal to 300/μL. Subjects were randomly assigned (1:1:1:1) to dexpramipexole 37.5, 75, or 150 mg BID (twice-daily) or placebo. The primary end point was the relative change in AEC from baseline to week 12. Prebronchodilator FEV1 week-12 change from baseline was a key secondary end point. Nasal eosinophil peroxidase was an exploratory end point.

RESULTS

A total of 103 subjects were randomly assigned to dexpramipexole 37.5 mg BID (N = 22), 75 mg BID (N = 26), 150 mg BID (N = 28), or placebo (N = 27). Dexpramipexole significantly reduced placebo-corrected AEC week-12 ratio to baseline, in both the 150-mg BID (ratio, 0.23; 95% CI, 0.12-0.43; P < .0001) and the 75-mg BID (ratio, 0.34; 95% CI, 0.18-0.65; P = .0014) dose groups, corresponding to 77% and 66% reductions, respectively. Dexpramipexole reduced the exploratory end point of nasal eosinophil peroxidase week-12 ratio to baseline in the 150-mg BID (median, 0.11; P = .020) and the 75-mg BID (median, 0.17; P = .021) groups. Placebo-corrected FEV1 increases were observed starting at week 4 (nonsignificant). Dexpramipexole displayed a favorable safety profile.

CONCLUSIONS

Dexpramipexole demonstrated effective eosinophil lowering and was well tolerated. Additional larger clinical trials are needed to understand the clinical efficacy of dexpramipexole in asthma.