Prediction of response to biological treatment with monoclonal antibodies in severe asthma

Safety of Biological Therapies for Severe Asthma: An Analysis of Suspected Adverse Reactions Reported in the WHO Pharmacovigilance Database

BACKGROUND

The management of uncontrolled severe asthma has greatly improved since the advent of novel biologic therapies. Up to August 2022, five biologics have been approved for the type 2 asthma phenotype: anti-IgE (omalizumab), anti-IL5 (mepolizumab, reslizumab, benralizumab), and anti-IL4 (dupilumab) monoclonal antibodies. These drugs are usually well tolerated, although long-term safety information is limited, and some adverse events have not yet been fully characterized. Spontaneous reporting systems represent the cornerstone for the detection of potential signals and evaluation of the real-world safety of all marketed drugs.

OBJECTIVE

The aim of this study was to provide an overview of safety data of biologics for severe asthma using VigiBase, the World Health Organization global pharmacovigilance database.

METHODS

We selected all de-duplicated individual case safety reports (ICSRs) attributed to five approved biologics for severe asthma in VigiBase, up to 31st August 2022 (omalizumab, mepolizumab, reslizumab, benralizumab and dupilumab). Descriptive frequency analyses of ICSRs were carried out both as a whole class and as individual products. Reporting odds ratios (ROR) with 95% confidence intervals (CIs) were used as the measure of disproportionality for suspected adverse drug reactions (ADRs) associated with the study drugs compared with either all other suspected drugs (Reference Group 1, RG1) or inhaled corticosteroids plus long-acting β-agonists (ICSs/LABAs) (Reference Group 2, RG2) or with oral corticosteroids (OCSs) (Reference Group 3, RG3).

RESULTS

Overall, 31,724,381 ICSRs were identified in VigiBase and 167,282 (0.5%) were related to study drugs; the remaining reports were considered as RG1. Stratifying all biologic-related ICSRs by therapeutic indication, around 29.4% (n = 48,440) concerned asthma use; omalizumab was mainly indicated as the suspected drug (n = 20,501), followed by dupilumab, mepolizumab, benralizumab and reslizumab. Most asthma ICSRs concerned adults (57%) and women (64.1%). Asthma biologics showed a higher frequency of serious suspected ADR reporting than RG1 (41.3% vs 32.3%). The most reported suspected ADRs included asthma, dyspnea, product use issue, drug ineffective, cough, headache, fatigue and wheezing. Asthma biologics were disproportionally associated with several unknown or less documented adverse events, such as malignancies, pulmonary embolism and deep vein thrombosis with omalizumab; alopecia and lichen planus with dupilumab; alopecia and herpes infections with mepolizumab; alopecia, herpes zoster and eosinophilic granulomatosis with polyangiitis related to benralizumab; and alopecia with reslizumab.

CONCLUSIONS

The most frequently reported suspected ADRs of asthma biologics in VigiBase confirmed the presence of well-known adverse effects such as general disorders, injection-site reactions, nasopharyngitis, headache and hypersensitivity, while some others (e.g. asthma reactivation or therapeutic failure) could be ascribed to the indication of use. Moreover, the analysis of signals of disproportionate reporting suggests the presence of malignancies, effects on the cardiovascular system, alopecia and autoimmune conditions, requiring further assessment and investigation.

Predictors of Early and Late Lung Function Improvement in Severe Eosinophilic Asthma on Type2-Biologics in the PRISM Study

BACKGROUND

The determinants linked to the short- and long-term improvement in lung function in patients with severe eosinophilic asthma (SEA) on biological treatment (BioT) remain elusive.

OBJECTIVE

We sought to identify the predictors of early and late lung function improvement in patients with SEA after BioT.

METHODS

140 adult patients with SEA who received mepolizumab, dupilumab, or reslizumab were followed up for 6 months to evaluate improvement in forced expiratory volume in one second (FEV1). Logistic regression was used to determine the association between potential prognostic factors and improved lung function at 1 and 6 months of treatment.

RESULTS

More than a third of patients with SEA using BioT showed early and sustained improvements in FEV1 after 1 month. A significant association was found between low baseline FEV1 and high blood eosinophil count and sustained FEV1 improvement after 1 month (0.54 [0.37-0.79] and 1.88 [1.28-2.97] odds ratios and 95% confidence interval, respectively). Meanwhile, among patients who did not experience FEV1 improvement after 1 month, 39% exhibited improvement at 6 months follow-up. A high ACT score measured at this visit was the most reliable predictor of late response after 6 months of treatment (OR and 95% CI 1.75 [1.09-2.98]).

CONCLUSION

Factors predicting the efficacy of biological agents that improve lung function in SEA vary according to the stage of response.

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.

An early Indian experience with benralizumab - A compendium on severe asthma cases: a case series

Background: Severe eosinophilic asthma (SEA), one of the phenotypes of asthma that is characterized by elevated blood eosinophil counts, is a common cause of uncontrolled asthma. Patients with SEA often experience severe persistent symptoms and have frequent exacerbations despite optimal inhaler therapy. They also have poor lung function and quality of life (QoL). Benralizumab (Fasenra), a monoclonal antibody, has been approved for managing cases of SEA. This series of six cases, the first of its kind from India, aims to add to the real-world evidence of benralizumab in India. Methods: Benralizumab 30 mg (once in four weeks for the first three doses followed by a dose every eight weeks for two years) was administered in six patients with symptoms of cough, breathlessness on exertion, and wheezing, diagnosed with SEA. The following were the endpoints assessed: (i) overlap between high immunoglobulin E (IgE) and eosinophilic asthma; (ii) reduction of exacerbations; (iii) withdrawal of oral corticosteroids; and (iv) improvement in lung function and QoL. Results: In all cases, management with benralizumab resulted in optimal clinical and functional improvement, a decline in systemic steroid use, and improved QoL. Conclusions: The cases presented here are the first of their kind in the Indian asthmatic population with all SEA patients demonstrating significant improvement in symptoms with the use of benralizumab.

Severe Asthma and Biological Therapies: Now and the Future

Recognition of phenotypic variability in pediatric asthma allows for a more personalized therapeutic approach. Knowledge of the underlying pathophysiological and molecular mechanisms (endotypes) of corresponding biomarkers and new treatments enables this strategy to progress. Biologic therapies for children with severe asthma are becoming more relevant in this sense. The T2 phenotype is the most prevalent in childhood and adolescence, and non-T2 phenotypes are usually rare. This document aims to review the mechanism of action, efficacy, and potential predictive and monitoring biomarkers of biological drugs, focusing on the pediatric population. The drugs currently available are omalizumab, mepolizumab, benralizumab, dupilumab, and 1ezepelumab, with some differences in administrative approval prescription criteria between the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Previously, we described the characteristics of severe asthma in children and its diagnostic and therapeutic management.

Criteria for evaluation of response to biologics in severe asthma - the Biologics Asthma Response Score (BARS)

BACKGROUND

 The introduction of monoclonal antibodies (biologics) has revolutionized the therapy of severe asthma. Even though there is a response in the majority of patients, the degree of response varies. To date criteria for assessment of response to biologics are not consistently defined.

AIM

 To define criteria for evaluation of response to biologics that are precise, simple and suitable for daily use in order to guide decision-making regarding continuation, switching or stopping of biological therapy.

METHODS

 8 physicians with large experience in this indication, supported by a data-scientist, developed a consensus on criteria to evaluate response to biologics in patients with severe asthma.

RESULT

 We developed a combined score based on current literature, own experience and practicability. It uses the main criteria exacerbations, oral corticosteroid (OCS) therapy and asthma control (asthma control test, ACT). We defined thresholds for "good response", "response" and "insufficient response" rated with a score of "2", "1" and "0" respectively: annual exacerbations ("0 or reduction ≥ 75 %", "reduction 50-74 %", "reductio < 50 %"), daily OCS dose ("stopping or reduction ≥ 75 %", "reduction 50-74 %", "reduction < 50 %"), asthma control ("ACT increase ≥ 6 or ≥ 3 with result ≥ 20", "ACT increase 3-5 with result < 20", "ACT increase < 3"). Additional individual criteria like lung function and comorbidities may be important for evaluation of response. We propose 3, 6 and 12 months timepoint for assessment of tolerability and response. Using the combined score, we developed a scheme to guide the decision whether switching the biologic should be considered.

CONCLUSION

 The Biologic Asthma Response Score (BARS) serves as objective and simple tool to evaluate response to biologic therapy using the three main criteria exacerbations, OCS use and asthma control. A validation of the score was initiated.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Definitions of non-response and response to biological therapy for severe asthma: a systematic review

Background

Biologics have proven efficacy for patients with severe asthma but there is lack of consensus on defining response. We systematically reviewed and appraised methodologically developed, defined and evaluated definitions of non-response and response to biologics for severe asthma.

Methods

We searched four bibliographic databases from inception to 15 March 2021. Two reviewers screened references, extracted data, and assessed methodological quality of development, measurement properties of outcome measures and definitions of response based on COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). A modified GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach and narrative synthesis were undertaken.

Results

13 studies reported three composite outcome measures, three asthma symptoms measures, one asthma control measure and one quality of life measure. Only four measures were developed with patient input; none were composite measures. Studies utilised 17 definitions of response: 10 out of 17 (58.8%) were based on minimal clinically important difference (MCID) or minimal important difference (MID) and 16 out of 17 (94.1%) had high-quality evidence. Results were limited by poor methodology for the development process and incomplete reporting of psychometric properties. Most measures rated "very low" to "low" for quality of measurement properties and none met all quality standards.

Conclusions

This is the first review to synthesise evidence about definitions of response to biologics for severe asthma. While high-quality definitions are available, most are MCIDs or MIDs, which may be insufficient to justify continuation of biologics in terms of cost-effectiveness. There remains an unmet need for universally accepted, patient-centred, composite definitions to aid clinical decision making and comparability of responses to biologics.

Subsets of Eosinophils in Asthma, a Challenge for Precise Treatment

The existence of eosinophils was documented histopathologically in the first half of the 19th century. However, the term “eosinophils” was first used by Paul Ehrlich in 1878. Since their discovery and description, their existence has been associated with asthma, allergies, and antihelminthic immunity. Eosinophils may also be responsible for various possible tissue pathologies in many eosinophil-associated diseases. Since the beginning of the 21st century, the understanding of the nature of this cell population has undergone a fundamental reassessment, and in 2010, J. J. Lee proposed the concept of “LIAR” (Local Immunity And/or Remodeling/Repair), underlining the extensive immunoregulatory functions of eosinophils in the context of health and disease. It soon became apparent that mature eosinophils (in line with previous morphological studies) are not structurally, functionally, or immunologically homogeneous cell populations. On the contrary, these cells form subtypes characterized by their further development, immunophenotype, sensitivity to growth factors, localization, role and fate in tissues, and contribution to the pathogenesis of various diseases, including asthma. The eosinophil subsets were recently characterized as resident (rEos) and inflammatory (iEos) eosinophils. During the last 20 years, the biological therapy of eosinophil diseases, including asthma, has been significantly revolutionized. Treatment management has been improved through the enhancement of treatment effectiveness and a decrease in the adverse events associated with the formerly ultimately used systemic corticosteroids. However, as we observed from real-life data, the global treatment efficacy is still far from optimal. A fundamental condition, “sine qua non”, for correct treatment management is a thorough evaluation of the inflammatory phenotype of the disease. We believe that a better understanding of eosinophils would lead to more precise diagnostics and classification of asthma subtypes, which could further improve treatment outcomes. The currently validated asthma biomarkers (eosinophil count, production of NO in exhaled breath, and IgE synthesis) are insufficient to unveil super-responders among all severe asthma patients and thus give only a blurred picture of the adepts for treatment. We propose an emerging approach consisting of a more precise characterization of pathogenic eosinophils in terms of the definition of their functional status or subset affiliation by flow cytometry. We believe that the effort to find new eosinophil-associated biomarkers and their rational use in treatment algorithms may ameliorate the response rate to biological therapy in patients with severe asthma.

[Criteria for evaluation of response to biologics in severe asthma - the Biologics Asthma Response Score (BARS)]

BACKGROUND

 The introduction of monoclonal antibodies (biologics) has revolutionized the therapy of severe asthma. Even though there is a response in the majority of patients, the degree of response varies. To date criteria for assessment of response to biologics are not consistently defined.

AIM

 To define criteria for evaluation of response to biologics that are precise, simple and suitable for daily use in order to guide decision-making regarding continuation, switching or stopping of biological therapy.

METHODS

 8 physicians with large experience in this indication, supported by a data-scientist, developed a consensus on criteria to evaluate response to biologics in patients with severe asthma.

RESULT

 We developed a combined score based on current literature, own experience and practicability. It uses the main criteria exacerbations, oral corticosteroid (OCS) therapy and asthma control (asthma control test, ACT). We defined thresholds for "good response", "response" and "insufficient response" rated with a score of "2", "1" and "0" respectively: annual exacerbations ("0 or reduction ≥ 75 %", reduction 50-74 %", "reductio  < 50 %"), daily OCS dose ("stopping or reduction ≥ 75 %", "reduction 50-74 %", "reduction < 50 %"), asthma control (ACT increase ≥ 6 or ≥ 3 with result ≥ 20", "ACT increase 3-5 with result < 20", "ACT increase < 3"). Additional individual criteria like lung function and comorbidities may be important for evaluation of response. We propose 3, 6 and 12 months timepoint for assessment of tolerability and response. Using the combined score, we developed a scheme to guide the decision whether switching the biologic should be considered.

CONCLUSION

 The Biologic Asthma Response Score (BARS) serves as objective and simple tool to evaluate response to biologic therapy using the three main criteria exacerbations, OCS use and asthma control. A validation of the score was initiated.

Defining response to therapy with biologics in severe asthma: from global evaluation to super response and remission

INTRODUCTION

In recent years, monoclonal antibodies targeting Type-2 inflammatory pathways have been developed for severe asthma treatment. However, even when patients are carefully selected, the response to treatment varies.

AREAS COVERED

Different studies have evaluated response to therapy with biologics such as exacerbation reduction, symptom improvement, pulmonary function increase, improvement in QoL, or decrease of oral corticosteroids, showing that all patients do not respond to all disease aspects and leading to an extensive debate regarding the definition of response.

EXPERT OPINION

Assessing response to therapy is of great importance, but since there is no uniform definition of treatment response, the recognition of patients who really benefit from these therapies remains an unmet need. In the same context, identifying non-responding patients in which biologic therapy should be switched or substituted by alternative treatment options is of paramount importance. In this review, we present the road trip of the definition of therapeutic response to biologics in severe asthmatics by presenting the current relevant medical literature. We also present the suggested predictors of response, with an emphasis on the so-called super-responders. Finally, we discuss the recent insights regarding asthma remission as a feasible treatment goal and provide a simple algorithm for the evaluation of response.

α-Asarone alleviates allergic asthma by stabilizing mast cells through inhibition of ERK/JAK2-STAT3 pathway

Asthma is a heterogeneous disease related to numerous inflammatory cells, among which mast cells play an important role in the early stages of asthma. Therefore, treatment of asthma targeting mast cells is of great research value. α-Asarone is an important anti-inflammatory component of the traditional Chinese medicine Acorus calamus L, which has a variety of medicinal values. To investigate whether α-asarone can alleviate asthma symptoms and its mechanism. In this study, we investigated the effect of α-asarone on mast cell activation in vivo and in vitro. The release of chemokines or cytokines, AHR (airway hyperresponsiveness), and mast cell activation were examined in a mast cell-dependent asthma model. Western blot was performed to determine the underlying pathway. α-Asarone inhibited the degranulation of LAD2 (laboratory allergic disease 2) cells and decreased IL-8, MCP-1, histamine, and TNF-α in vitro. α-Asarone reduced paw swelling and leakage of Evans blue, as well as serum histamine, CCL2, and TNF-α in vivo. In the asthma model, α-asarone showed an inhibitory effect on AHR, inflammation, mast cells activation, infiltration of inflammatory cells, and the release of IL-5 and IL-13 in lung tissue. α-Asarone decreased the levels of phosphorylated JAK2, phosphorylated ERK, and phosphorylated STAT3 induced by C48/80. Our findings suggest that α-asarone alleviates allergic asthma by inhibiting mast cell activation through the ERK/JAK2-STAT3 pathway.

Characterization of Selective and Potent JAK1 Inhibitors Intended for the Inhaled Treatment of Asthma

Purpose

Janus kinase 1 (JAK1) is implicated in multiple inflammatory pathways that are critical for the pathogenesis of asthma, including the interleukin (IL)-4, IL-5, IL-13, and thymic stromal lymphopoietin cytokine signaling pathways, which have previously been targeted to treat allergic asthma. Here, we describe the development of AZD0449 and AZD4604, two novel and highly selective JAK1 inhibitors with promising properties for inhalation.

Methods

The effects of AZD0449 and AZD4604 in JAK1 signaling pathways were assessed by measuring phosphorylation of signal transducer and activator of transcription (STAT) proteins and chemokine release using immunoassays of whole blood from healthy human volunteers and rats. Pharmacokinetic studies performed on rats evaluated AZD0449 at a lung deposited dose of 52 μg/kg and AZD4604 at 30 µg/kg. The efficacy of AZD0449 and AZD4604 was assessed by evaluating lung inflammation (cell count and cytokine levels) and the late asthmatic response (average enhanced pause [Penh]).

Results

Both compounds inhibited JAK1-dependent cytokine signaling pathways in a dose-dependent manner in human and rat leukocytes. After intratracheal administration in rats, both compounds exhibited low systemic exposures and medium-to-long terminal lung half-lives (AZD0449, 34 hours; AZD4604, 5 hours). Both compounds inhibited STAT3 and STAT5 phosphorylation in lung tissue from ovalbumin (OVA)-challenged rats. AZD0449 and AZD4604 also inhibited eosinophilia in the lung and reduced the late asthmatic response, measured as Penh in the OVA rat model.

Conclusion

AZD0449 and AZD4604 show potential as inhibitors of signaling pathways involved in asthmatic immune responses, with target engagement demonstrated locally in the lung. These findings support the clinical development of AZD0449 and AZD4604 for the treatment of patients with asthma.

Severe asthma and personalized approach in the choice of biologic

PURPOSE OF REVIEW

Severe asthma requires intensive pharmacological treatment to achieve disease control. Oral corticosteroids are effective, but their use is burdened with important side effects. Biologics targeting the specific inflammatory pathways underpinning the disease have been shown to be effective but not all patients respond equally well. As we treat more patients than those who can respond, our inability to predict responders has important healthcare costs considering that biologics are expensive drugs. Thus, a more precise choice of the 'right patients' to be prescribed with the 'right biologics' would be desirable.

RECENT FINDINGS

Machine learning techniques showed that it is possible to increase our ability to predict outcomes in patients treated with biologics. Recently, we identified by cluster analysis four different clusters within the T2 high phenotype with differential benralizumab response. Two of these clusters, characterized by higher levels of inflammatory markers, showed the highest response rate (80-90%).

SUMMARY

Machine learning holds promise for asthma research enabling us to predict which patients will respond to which drug. These techniques can facilitate the diagnostic workflow and increase the chance of selecting the more appropriate treatment option for the individual patient, enhancing patient care and satisfaction.

Clinical response to biologics for severe asthma: any relevance for sex in different age ranges?

Background

Whether sex can influence the clinical response to biological treatment in patients with severe asthma has not been fully addressed.

Aims and methods

The aim of this study was to investigate in patients with severe asthma undergoing biological treatment the individual evolution of lung function measurements and patient-reported asthma control scores over a 12-month follow-up period, in relation to patients’ sex, in different age ranges. Second, the change in the administered dose of oral corticosteroids (OCS) before and after 12 months of treatment was investigated.

Results

64 patients (58% female and 42% male) with a median age of 52 years were enrolled in the study. There were no relevant differences between sexes in terms of lung function, patient-reported asthma control, exacerbation rate and daily OCS dose within the study timeframe. A separate sub-analysis by biological treatment confirmed the same finding. Stratifying individuals by age, we showed that older men had lower lung function parameter values (forced expiratory volume in 1 s (FEV₁) % predicted and FEV₁/forced vital capacity index) than older women, whereas an opposite trend was observed in terms of Asthma Control Test score. No other relevant differences were detected after age stratification.

Conclusion

According to our findings, sex does not act as a determinant of treatment response to biologicals in people with severe asthma. Although to be confirmed in larger studies, our data suggest that neither sex nor age should limit biological treatment prescription, once the eligibility criteria for that therapy are satisfied.

Sex does not seem to act as a determinant of treatment response to biologicals in severe asthma. Neither sex nor age should limit biological treatment prescription, once the eligibility criteria for that therapy are satisfied.https://bit.ly/370frEP

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

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

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

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

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

The pan-JAK inhibitor LAS194046 reduces neutrophil activation from severe asthma and COPD patients in vitro

Non-T2 severe asthma and chronic obstructive pulmonary disease (COPD) are airway chronic inflammatory disorders with a poor response to corticosteroids. LAS194046, a novel pan-Janus kinase (JAK) inhibitor, shows inhibitory effects on T2 allergic lung inflammation in rats. In this work we analyze the effects of LAS194046, fluticasone propionate and their combination in neutrophils from non-T2 severe asthma and COPD patients in vitro. Neutrophils from 23 healthy subjects, 23 COPD and 21 non-T2 severe asthma patients were incubated with LAS194046 (0.01 nM–1 µM), fluticasone propionate (0.1 nM–1 µM) or their combination and stimulated with lipopolysaccharide (LPS 1 µM). LAS194046 shows similar maximal % inhibition and potency inhibiting IL-8, MMP-9 and superoxide anion release in neutrophils from healthy, COPD and asthma. Fluticasone propionate suppresses mediator release only in neutrophils from healthy patients. The combination of LAS194046 with fluticasone propionate shows synergistic anti-inflammatory and anti-oxidant effects. The mechanisms involved in the synergistic effects of this combination include the increase of MKP1 expression, decrease of PI3Kδ, the induction of glucocorticoid response element and the decrease of ERK1/2, P38 and JAK2/STAT3 phosphorylation compared with monotherapies. In summary, LAS194046 shows anti-inflammatory effects in neutrophils from COPD and severe non-T2 asthma patients and induces synergistic anti-inflammatory effects when combined with fluticasone propionate.

Clinical Characteristics of Patients and Factors Associated with Switching Biologics in Asthma

Purpose

Biologics have been used increasingly for the treatment of severe asthma. However, established guidelines for the selection, switching, or discontinuation of biologics do not exist. We aimed to identify the clinical characteristics of patients with asthma who required switching biologics and the factors associated with switching biologics.

Patients and Methods

This was a retrospective study of 42 patients with severe asthma treated with biologics at the Hokkaido University Hospital between 23^rd June 2016 and 30^th April 2021, when two biologics were available in Japan. We compared the characteristics of subjects who continued and switched biologics. The time to switch the biologics was assessed by type 2 inflammatory biomarkers, pulmonary function indices, and the presence of comorbidities, including the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) score and aspirin exacerbated respiratory diseases (AERD), using the Kaplan–Meier method and a multivariate Cox proportional hazards model.

Results

Eight and five patients were treated by mepolizumab and benralizumab at baseline, respectively among the 31% (13/42) who switched the biologics. Subjects who required switching biologics were characterized by high blood eosinophil counts, younger age, JESREC scores of 11 points or higher, and AERD. The time taken to switch biologics was significantly shorter in the subgroups with high JESREC scores (≥11) or AERD, compared with their counterparts with low JESREC scores or without AERD (both, P < 0.05). JESREC scores of ≥11, but not the presence of AERD, were associated with time to switch biologics.

Conclusion

The presence of eosinophilic chronic rhinosinusitis based on JESREC scores of ≥11 and younger age were factors associated with switching biologics in asthma.

Heterogeneous Response of Airway Eosinophilia to Anti-IL-5 Biologics in Severe Asthma Patients

Many questions concerning responders (R) and nonresponders (NR) in severe eosinophilic asthma (SEA) after blocking the IL-5 (interleukin 5) pathway are still not clear, especially regarding the early parameters of response to biologics in personalized treatment strategies. We evaluated 17 SEA patients treated with anti-IL-5 biologics (16 patients mepolizumab, one patient benralizumab) before the introduction of biologics, and at a week 16 follow-up. Clinical, cellular and immunological parameters in peripheral blood were measured in R and NR. Sputum induction with the measurement of cellular and immunological parameters was performed at 16 weeks only. There were 12 R and 5 NR to biologics. After 16 weeks, there was a significant improvement in percentages of FEV1 (p = 0.001), and asthma control test (ACT) (p = 0.001) in the R group, but not in NR. After 16 weeks, the eosinophils in induced sputum were 27.0% in NR and 4.5% in R (p = 0.05), with no difference in IL-5 concentrations (p = 0.743). Peripheral eosinophilia decreased significantly in NR (p = 0.032) and R (p = 0.002). In patients with SEA on anti-IL-5 therapy, there was a marked difference in airway eosinophilic inflammation between R and NR already at 16 weeks, after anti-IL-5 introduction.

Outcomes over the first two years of treatment with mepolizumab in severe asthma

Mepolizumab was the first anti-interleukin-5 (anti-IL-5) monoclonal antibody licensed for the treatment of severe asthma, recommended as add-on treatment in patients with frequent exacerbations or requiring maintenance oral corticosteroids (OCS) despite optimal inhaled therapy [1, 2]. In clinical trials it reduced exacerbation rates and OCS use, and improved lung function, asthma control and health-related quality of life over the first year of treatment [3–6]. Current guidance states that anti-IL-5 biologics should be continued long term if benefit is demonstrated over the first year, yet little is known about whether initial responses are sustained, or whether they can be predicted by clinical characteristics.

This study found that 30% of patients stopped mepolizumab in the second year of treatment. Those with a sustained response had lower blood eosinophils and better asthma control questionnaire scores prior to starting mepolizumab.https://bit.ly/3ChWN63

Variability of Type 2 inflammatory markers guiding biologic therapy of severe asthma: A 5-year retrospective study from a single tertiary hospital

Background

Currently, biotherapy is mainly administered to treat patients with severe asthma with the Type 2 (T2) inflammation phenotype. The variability of T2 inflammatory markers remains poorly understood.

Objective

We aimed to describe the individual distributions of different biomarkers at varying thresholds and their variation patterns in participants with severe asthma.

Methods

We retrospectively reviewed the data of participants who had completed 2 or more fraction of exhaled nitric oxide (FeNO) and peripheral blood eosinophil counts in our centre within 5 years. The individual distribution of biomarkers (blood or sputum eosinophils, FeNO, and serum total IgE) with repeated measurements at different thresholds was analysed. The varied patterns of biomarkers were analysed by cluster analysis.

Results

A total of 241 eligible participants were screened. Through long-term longitudinal multiple measurements, we found that approximately 50% of severe asthmatics had blood eosinophil levels fluctuating around the threshold defined by biological agents. FeNO persisted at levels >19.5 ppb or 25 ppb in more than half of patients; about 30% of participants crossed this threshold. In our centre, 47.4% of participants consistently exceeded sputum eosinophils >3%, and 47.4% of patients crossed this threshold. Approximately 66.7% of participants had more than 50% alterations of serum total IgE, and 98.1% of participants continued to have IgE levels greater than 30 IU/mL. We used cluster analysis to classify variability and levels of FeNO and blood eosinophils and identified 4 patient clusters. Cluster 1 can be summarised as T2 severe asthma with low blood eosinophil levels and stability. Cluster 2 can be summarised as asthma with continuous increase and small fluctuations in various T2 inflammatory markers. Cluster 3 can be summarised as a non/low-T2 inflammatory phenotype. Cluster 4 can be summarised as a stable, moderate T2 inflammatory phenotype.

Conclusion

We identified the distributions and variable patterns of the T2 inflammatory markers currently used to guide asthma biotherapy in clinical practice. The longitudinal comprehensive multiple assessments of T2 inflammatory markers provide support for initiating biologic therapy patients with severe asthma whose biomarker levels vary.

Effectiveness of benralizumab in severe eosinophilic asthma: Distinct sub-phenotypes of response identified by cluster analysis

BACKGROUND

Benralizumab is effective in severe eosinophilic asthma (SEA), but suboptimal responses are observed in some patients. Although several factors have been associated with benralizumab response, no cluster analysis has yet been undertaken to identify different responsiveness sub-phenotypes.

OBJECTIVE

To identify SEA sub-phenotypes with differential responsiveness to benralizumab.

METHODS

One hundred and five patients diagnosed with SEA who had completed 6 months of benralizumab treatment were included in a hierarchical cluster analysis based on a set of clinical variables that can be easily collected in routine practice (age, age at disease onset, disease length, allergen sensitization status, blood eosinophil count, IgE levels, FEV₁ % predicted, nasal polyposis, bronchiectasis).

RESULTS

Four clusters were identified: Clusters 2 and 3 included patients with high levels of both IgE and eosinophils (type-2 biomarkers high), whereas Clusters 1 and 4 included patients with only one type-2 biomarker at a high level: IgE in Cluster 1 and eosinophils in Cluster 4. Clusters 2 and 3 (both type-2 biomarkers high) showed the highest response rate to benralizumab in terms of elimination of exacerbations (79% and 80% respectively) compared to Clusters 1 and 4 (52% and 60% respectively). When super-response (the absence of exacerbation without oral corticosteroid use) was assessed, Cluster 2, including patients with more preserved lung function than the other clusters, but comparable exacerbation rate, oral corticosteroid use and symptom severity, was the most responsive cluster (87.5% of patients).

CONCLUSIONS

Our cluster analysis identified benralizumab differential response sub-phenotypes in SEA, with the potential of improving disease treatment and precision management.

Eosinophils as Drivers of Severe Eosinophilic Asthma: Endotypes or Plasticity?

Asthma is now recognized as a heterogeneous disease, encompassing different phenotypes driven by distinct pathophysiological mechanisms called endotypes. Common phenotypes of asthma, referred to as eosinophilic asthma, are characterized by the presence of eosinophilia. Eosinophils are usually considered invariant, terminally differentiated effector cells and have become a primary therapeutic target in severe eosinophilic asthma (SEA) and other eosinophil-associated diseases (EADs). Biological treatments that target eosinophils reveal an unexpectedly complex role of eosinophils in asthma, including in SEA, suggesting that "not all eosinophils are equal". In this review, we address our current understanding of the role of eosinophils in asthma with regard to asthma phenotypes and endotypes. We further address the possibility that different SEA phenotypes may involve differences in eosinophil biology. We discuss how these differences could arise through eosinophil "endotyping", viz. adaptations of eosinophil function imprinted during their development, or through tissue-induced plasticity, viz. local adaptations of eosinophil function through interaction with their lung tissue niches. In doing so, we also discuss opportunities, technical challenges, and open questions that, if addressed, might provide considerable benefits in guiding the choice of the most efficient precision therapies of SEA and, by extension, other EADs.

Treating severe asthma: Targeting the IL-5 pathway

Severe asthma is a heterogeneous disease with different phenotypes based on clinical, functional or inflammatory parameters. In particular, the eosinophilic phenotype is associated with type 2 inflammation and increased levels of interleukin (IL)-4, IL-5 and IL-13). Monoclonal antibodies that target the eosinophilic inflammatory pathways (IL-5R and IL-5), namely mepolizumab, reslizumab, and benralizumab, are effective and safe for severe eosinophilic asthma. Eosinophils threshold represents the most indicative biomarker for response to treatment with all three monoclonal antibodies. Improvement in asthma symptoms scores, lung function, the number of exacerbations, history of late-onset asthma, chronic rhinosinusitis with nasal polyposis, low oral corticosteroids use and low body mass index represent predictive clinical markers of response. Novel Omics studies are emerging with proteomics data and exhaled breath analyses. These may prove useful as biomarkers of response and non-response biologics. Moreover, future biomarker studies need to be undertaken in paediatric patients affected by severe asthma. The choice of appropriate biologic therapy for severe asthma remains challenging. The importance of finding biomarkers that can predict response continuous an open issue that needs to be further explored. This review describes the clinical effects of targeting the IL-5 pathway in severe asthma in adult and paediatric patients, focusing on predictors of response and non-response.

Asthma and Chronic Rhinosinusitis: How Similar Are They in Pathogenesis and Treatment Responses?

Severe asthma and rhinosinusitis represent frequent comorbidities, complicating the overall management of the disease. Both asthma and chronic rhinosinusitis (CRS) can be differentiated into endotypes: those with type 2 eosinophilic inflammation and those with a non-type 2 inflammation. A correct definition of phenotype/endotype for these diseases is crucial, taking into account the availability of novel biological therapies. Even though patients suffering from type 2 severe asthma-with or without CRS with nasal polyps-significantly benefit from treatment with biologics, the existence of different levels of patient response has been clearly demonstrated. In fact, in clinical practice, it is a common experience that patients reach a good clinical response for asthma symptoms, but not for CRS. At first glance, a reason for this could be that although asthma and CRS can coexist in the same patient, they can manifest with different degrees of severity; therefore, efficacy may not be equally achieved. Many questions regarding responders and nonresponders, predictors of response, and residual disease after blocking type 2 pathways are still unanswered. In this review, we discuss whether treatment with biological agents is equally effective in controlling both asthma and sinonasal symptoms in patients in which asthma and chronic rhinosinusitis with nasal polyps coexist.

Development of a Tool to Measure the Clinical Response to Biologic Therapy in Uncontrolled Severe Asthma: The FEV1, Exacerbations, Oral Corticosteroids, Symptoms Score

BACKGROUND

There is a lack of tools to quantify the response to monoclonal antibodies (mAbs) holistically in severe uncontrolled asthma patients.

OBJECTIVE

To develop a valid score to assist specialists in this clinical context.

METHODS

The score was developed in four subsequent phases: (1) elaboration of the theoretical model of the construct intended to be measured (response to mAbs); (2) definition and selection of items and measurement instruments by Delphi survey; (3) weight assignment of the selected items by multicriteria decision analysis using the Potentially All Pairwise RanKings of All Possible Alternatives methodology using the 1000minds software; and (4) face validity assessment of the obtained score.

RESULTS

Four core items, with different levels of response for each, were selected: severe exacerbations, oral corticosteroid use, symptoms (evaluated by Asthma Control Test), and bronchial obstruction (assessed by FEV₁ percent predicted). Severe exacerbations and oral corticosteroid maintenance dose were weighted most heavily (38% each), followed by symptoms (13%) and FEV₁ (11%). Higher scores in the weighted system indicate a better response and the range of responses runs from 0 (worsening) to 100 (best possible response). Face validity was high (intraclass correlation coefficient of 0.86).

CONCLUSIONS

The FEV₁, exacerbations, oral corticosteroids, symptoms score allows clinicians to quantify response in severe uncontrolled asthma patients who are being treated with mAbs.

Clinical and histopathologic predictors of therapeutic response to bronchial thermoplasty in severe refractory asthma

BACKGROUND

Phenotypes and endotypes predicting optimal response to bronchial thermoplasty (BT) in patients with severe asthma remain elusive.

OBJECTIVE

Our aim was to compare the clinical characteristics and hallmarks of airway inflammation and remodeling before and after BT in responder and partial responder patients with severe asthma refractory to oral steroids and to omalizumab.

METHODS

In all, 23 patients with severe refractory asthma were divided into BT responders (n = 15) and BT partial responders (n = 8), according to the decrease in asthma exacerbations at 12 months after BT. Clinical parameters were compared at baseline and 12 months after BT, and hallmarks of airway inflammation and remodeling were analyzed by immunohistochemistry in bronchial biopsy specimens before and 3 months after BT.

RESULTS

At baseline, the BT responders were around 8 years younger than the BT partial responders (P = .02) and they had a greater incidence of atopy, higher numbers of blood eosinophils (both P = .03) and IgE levels, higher epithelial IFN-α expression, and higher numbers of mucosal eosinophils and IL-33-positive cells (P ≤ .05). A reduction in blood eosinophil count, serum IgE level, type 2 airway inflammation, and numbers of mucosal IL-33-positive cells and mast cells associated with augmented epithelial MUC5AC and IFN-α/β immunostaining was noted after BT in responders, whereas the numbers of mucosal IL-33-positive cells were augmented in BT partial responders. Most of these changes were correlated with clinical parameters. Subepithelial membrane thickening and airway smooth muscle area were similar in the 2 patient groups at baseline and after BT.

CONCLUSION

By reducing allergic type 2 inflammation and increasing epithelial MUC5AC and anti-viral IFN-α/β expression, BT may enhance host immune responses and thus attenuate exacerbations and symptoms in BT responders. Instead, targeting IL-33 may provide a clinical benefit in BT partial responders.

A snapshot of exhaled nitric oxide and asthma characteristics: experience from high to low income countries

Nitric oxide is a gas produced in the airways of asthmatic subjects and related to T2 inflammation. It can be measured as fractional nitric oxide (FeNO) in the exhaled air and used as a non-invasive, easy to evaluate, rapid marker. It is now widely used in many settings to determine airway inflammation. The aim of this narrative review is to report relationship between FeNO and the physiopathologic characteristics of asthmatic patients. Factors affecting FeNO levels have also been analysed as well as the impact of corticosteroid, target therapies and rehabilitation programs. Considering the availability of the test, spreading this methodology to low income countries has also been considered as a possibility for evaluating airway inflammation and monitoring adherence to inhaled corticosteroid therapy. PubMed data search has been performed restricted to English language papers. Research was limited to studies in adults unless studies in children were the only ones reported for a particular issue. This revision could be useful to summarize the role of FeNO in relation to asthma characteristics and help in the use of FeNO in different clinical settings particularly in low income countries.

Long-Term Therapy Response to Anti-IL-5 Biologics in Severe Asthma-A Real-Life Evaluation

BACKGROUND

Patients with severe eosinophilic asthma show different responses to various anti-IL-5 biologics, ranging from super response to nonresponse. Residual disease manifestations observed in partial responders may prompt physicians to switch between biologics. More data on response, switches, and residual disease manifestations are needed to improve personalized treatment.

OBJECTIVE

To assess (1) prevalences and predictors of super, partial, and nonresponders to long-term anti-IL-5 treatment, (2) frequency and reasons for switches between anti-IL-5 biologics, and (3) nature of residual disease manifestations.

METHODS

In this 2-year follow-up study, patients with severe asthma were included who initiated an anti-IL-5 biologic (mepolizumab, reslizumab, benralizumab) (n = 114). Patient characteristics (clinical, functional, inflammatory) and comorbidities were collected at baseline and 2-year follow-up. "Super responders" showed no residual disease manifestations at 2-year follow-up, "partial responders" experienced residual disease manifestations, and "nonresponders" discontinued anti-IL-5 treatment after less than 2 years because of clinical worsening.

RESULTS

After 2-year anti-IL-5 treatment, 14% of patients were super responders, 69% partial responders, and 11% nonresponders. Super response was predicted by shorter asthma duration and higher FEV₁, and tended to be associated with adult-onset asthma, absence of nasal polyps, and lower body mass index. Switches between anti-IL-5 biologics occurred frequently (41%). After 2-year treatment, most common residual disease manifestations included impaired lung function (59%), uncontrolled sinonasal disease (58%), and uncontrolled asthma symptoms (48%).

CONCLUSIONS

After 2 years of anti-IL-5 treatment, a favorable response was found in 83% of patients with severe asthma, including a super response in 14%. Most partial responders show impaired lung function or uncontrolled sinonasal disease, causing physicians to switch between biologics.