Comparative Efficacy of Anti IL-4, IL-5 and IL-13 Drugs for Treatment of Eosinophilic Asthma: A Network Meta-analysis

Head-To-Head Comparison of Biologic Efficacy in Asthma: What Have We Learned?

We performed an in-depth appraisal of indirect head-to-head comparisons of biologics approved for asthma, including anti-IL5/5Rα (mepolizumab, benralizumab), anti-IL4Rα (dupilumab), anti-TSLP (tezepelumab) and anti-IgE (omalizumab), which was neither a systematic review nor a meta-analysis. A crude evaluation of 95% CI's for rate ratios which excluded unity revealed greater overall reductions in annualised exacerbations with dupilumab versus either mepolizumab or benralizumab and also with tezepelumab versus benralizumab. Furthermore in patients with eosinophils ≥ 300/μL exacerbation rates were lower for tezepelumab, dupilumab and mepolizumab versus benralizumab; and with eosinophils< 150/μL for tezepelumab versus dupilumab. For lung function, no overall differences in FEV1 response were observed between drugs where there was considerable heterogeneity of overlapping 95% CI's. Dupilumab was superior to benralizumab for oscillometry-derived peripheral lung resistance and compliance, as well as for attenuation of mannitol airway hyperresponsiveness. There were no differences in asthma control or quality of life scores where the effect sizes were small, along with wide overlaps in 95% CI's. There is an unmet need for prospective pragmatic randomised controlled trials to directly compare biologics, especially to assess clinical remission in both type 2 high and low asthma patients. Real-life studies might also evaluate complete remission with different biologics to include outcomes such as inhaled corticosteroid sparing, small airways dysfunction using oscillometry, abolition of airway hyperresponsiveness and to assess mucus plugging and remodelling as wall thickening with imaging.

Proinflammatory Cytokines in Chronic Respiratory Diseases and Their Management

Pulmonary homeostasis can be agitated either by external environmental insults or endogenous factors produced during respiratory/pulmonary diseases. The lungs counter these insults by initiating mechanisms of inflammation as a localized, non-specific first-line defense response. Cytokines are small signaling glycoprotein molecules that control the immune response. They are formed by numerous categories of cell types and induce the movement, growth, differentiation, and death of cells. During respiratory diseases, multiple proinflammatory cytokines play a crucial role in orchestrating chronic inflammation and structural changes in the respiratory tract by recruiting inflammatory cells and maintaining the release of growth factors to maintain inflammation. The issue aggravates when the inflammatory response is exaggerated and/or cytokine production becomes dysregulated. In such instances, unresolving and chronic inflammatory reactions and cytokine production accelerate airway remodeling and maladaptive outcomes. Pro-inflammatory cytokines generate these deleterious consequences through interactions with receptors, which in turn initiate a signal in the cell, triggering a response. The cytokine profile and inflammatory cascade seen in different pulmonary diseases vary and have become fundamental targets for advancement in new therapeutic strategies for lung diseases. There are considerable therapeutic approaches that target cytokine-mediated inflammation in pulmonary diseases; however, blocking specific cytokines may not contribute to clinical benefit. Alternatively, broad-spectrum anti-inflammatory approaches are more likely to be clinically effective. Herein, this comprehensive review of the literature identifies various cytokines (e.g., interleukins, chemokines, and growth factors) involved in pulmonary inflammation and the pathogenesis of respiratory diseases (e.g., asthma, chronic obstructive pulmonary, lung cancer, pneumonia, and pulmonary fibrosis) and investigates targeted therapeutic treatment approaches.

Patient and clinician preferences for biologic treatments for severe uncontrolled asthma: a discrete choice experiment (DCE)

OBJECTIVES

To estimate the preferences of patients with asthma and asthma-treating clinicians for attributes of biologic treatments, to compare patients' and clinicians' preferences, and to better understand the reasons for their preferences.

METHODS

Adults with moderate-to-severe asthma and clinicians who treat asthma in the US completed a cross-sectional, online survey including a discrete choice experiment (DCE) that consisted of seven attributes spanning treatment efficacy, risk and convenience. Marginal utilities were estimated using a mixed logit model, and relative attribute importance scores calculated. Clinicians were also asked about the value of biomarker agnostic biologic treatments. The survey was followed by qualitative interviews targeting a sub-sample of survey participants, in which the rationale behind their survey responses was discussed.

RESULTS

In the DCE, both patients and clinicians placed the most importance on exacerbation and hospitalization rate reduction, and risk of injection site reaction. Patients valued location of administration more than clinicians. Rationale for individual-level preferences varied, with patients and clinicians reporting their preference depended on event frequency and anticipated quality of life impacts. Clinicians mentioned compliance and financial impacts, while patients mentioned personal experience, particularly around site reactions. Most patients and clinicians would value a biomarker agnostic asthma treatment.

CONCLUSIONS

Asthma treatment preferences are largely driven by treatment efficacy and minimizing the risk of site reactions, although preferences differ between patients and clinicians across other attributes, highlighting the need for shared decision-making and individualized care.

Tralokinumab as an Alternative to Dupilumab in a Patient with Atopic Dermatitis and Asthma who Developed Hypereosinophilia: A Case Report

Abstract is missing (Short communication)

Effect of biologic therapies on quality of life in severe asthma: Findings from the PRISM study

Background

Anti-type 2 (T2) biologic therapies (biologics) improve exacerbation rates, lung function, and asthma-related quality of life (QoL) in patients with severe T2 asthma. However, studies comparing different biologics are lacking. We evaluated the QoL in patients with severe asthma comprehensively and compare the efficacy of different T2-directed biologics using QoL questionnaires.

Methods

We compared the QoL between severe and mild-to-moderate asthma and between severe asthma with and without biologics treatment. Data of mild-to-moderate were extracted from the Cohort for Reality and Evolution of Adult Asthma in Korea, and data of severe asthma were collected from the Precision Medicine Intervention in Severe Asthma. We included 183 patients with severe asthma treated with T2 biologics or conventional therapy between April 2020 and May 2021 and assessed QoL of them using the Questionnaire for Adult Korean Asthmatics (QLQAKA), Severe Asthma Questionnaire (SAQ), and EuroQoL-5Dimensions (EQ-5D) at baseline and 6 months.

Results

The EQ-5D index (0.803) of severe asthma was lower than that of other chronic diseases representing a worse QoL. The scores for all questions of QLQAKA, except "cough," were lower (less control) in the severe asthma group than in the mild-to-moderate asthma group at baseline and 6 months (P < 0.05). The total scores and subscores of all domains of the QLQAKA, SAQ, and EQ-5D improved significantly 6 months after biologic therapy but not after conventional therapy. The total QLQAKA, SAQ, and EQ-5D scores improved after 6 months in the anti-IL-5 (P < 0.05) and anti-IL-4/IL-13 (P < 0.05) treatment groups with no significant difference between groups (P > 0.05).

Conclusion

QoL was worse in severe asthma than in mild-to-moderate asthma and other chronic diseases. T2 biologics equally improved QoL in patients with severe asthma.

Comparative Effectiveness of Mepolizumab, Benralizumab, and Dupilumab among Patients with Difficult-to-Control Asthma: A Multicenter Retrospective Propensity-matched Analysis

Rationale: The comparative effectiveness of biologic agents used as add-on therapy in the management of difficult-to-control asthma is unclear. Objective: To compare the effectiveness of dupilumab, mepolizumab, and benralizumab among patients with difficult-to-control asthma. Methods: Retrospective multicenter cohort study of adult patients with difficult-to-control asthma starting treatment with dupilumab, mepolizumab, or benralizumab as documented in a multicenter electronic health record and claims-based database between October 19, 2018, and September 30, 2022. Propensity-score matching was used to minimize bias from nonrandomized treatment assignment; a prespecified α-level was set at 0.017 to account for three primary comparisons. The exposure of interest was the new initiation of dupilumab, benralizumab, or mepolizumab treatment. The primary outcome was the rate of asthma exacerbations in the 1 year after initiation of biologic therapy modeled using a negative binomial approach. Results: Among 893,668 patients with asthma who were prescribed an inhaled corticosteroid and were ⩾12 years old (65% female; mean age, 49 yr), 3,943 started dupilumab, 1,902 started benralizumab, and 2,012 started mepolizumab, all without an alternative indication for biologic therapy. After matching, there were 1,805 patients in each group for comparisons between dupilumab and benralizumab, 1,865 for comparisons between dupilumab and mepolizumab, and 1,721 for comparisons between mepolizumab and benralizumab. For all pairwise comparisons, covariates were well balanced after matching (all standardized mean differences <0.1). Patients who initiated dupilumab had a significantly lower rate of asthma exacerbations (1.07 per year) compared with benralizumab (1.47 per year), with a rate ratio (RR) of 0.73 (95% confidence interval, 0.63-0.85), and also had a significantly lower rate of asthma exacerbations compared with mepolizumab (1.04 per year vs. 1.45 per year), with an RR of 0.72 (0.62-0.84). There was no statistically significant difference in the rate of asthma exacerbations between mepolizumab (1.40 per year) and benralizumab (1.41 per year), with an RR of 1.00 (0.85-1.17). Conclusions: In patients with difficult-to-control asthma who had newly initiated biologic therapy, dupilumab was associated with a decreased rate of asthma exacerbations in the 1 year after initiation compared with mepolizumab or benralizumab.

Lung function trajectories in a cohort of patients with moderate-to-severe asthma on mepolizumab, omalizumab, or dupilumab

BACKGROUND

Lung function is an independent predictor of mortality. We evaluated the lung function trajectories of a cohort of patients with asthma receiving biologic therapy.

METHODS

We identified 229 monoclonal antibody-naïve adult patients with moderate-to-severe asthma who initiated omalizumab, mepolizumab, or dupilumab between 2010 and 2022 in a large healthcare system in Boston, MA. Generalized additive mixed models were used to estimate the lung function trajectories during the 156 weeks following biologic initiation. Response was defined as an improvement in FEV1 or a decrease of ≤0.5% per year. The Kaplan-Meier estimator was used to assess time to no additional improvement in FEV1 in responders. All models were adjusted for age, sex, body mass index, smoking status, baseline exacerbation rate, and baseline blood eosinophil count.

RESULTS

Eighty-eight patients initiated mepolizumab, 76 omalizumab, and 65 dupilumab. Baseline eosinophil count was highest in the mepolizumab group (405 cells/mcL) and lowest for omalizumab (250 cells/mcL). Both FEV1 and FVC improved in the mepolizumab group (FEV1 + 20 mL/year; FVC +43 mL/year). For omalizumab, there was an initial improvement in the first year followed by decline with an overall FEV1 loss of -44 mL/year and FVC -32 mL/year. For dupilumab, both FEV1 (+61 mL/year) and FVC (+74 mL/year) improved over time. Fifty percent of the mepolizumab group, 58% omalizumab, and 72% of dupilumab were responders. The median time to no additional FEV1 improvement in responders was 24 weeks for omalizumab, 48 weeks for mepolizumab, and 57 weeks for dupilumab.

CONCLUSION

In this clinical cohort, mepolizumab, omalizumab, and dupilumab had beneficial effects on FEV1 and FVC with distinct post-initiation trajectories.

Prospective direct comparison of biologic treatments for severe eosinophilic asthma: Findings from the PRISM study

BACKGROUND

Although various monoclonal antibodies have been used as add-on therapy for severe eosinophilic asthma (SEA), to the best of our knowledge, no direct head-to-head comparative study has evaluated their efficacy.

OBJECTIVE

To compare the efficacy of reslizumab, mepolizumab, and dupilumab in patients with SEA.

METHODS

This was a multicenter, prospective observational study in patients with SEA who had received 1 of these biologic agents for at least 6 months. Cox proportional hazard models were used to compare the risk of the first exacerbation event, adjusting for sputum or blood eosinophils and common asthma-related covariates. The annual exacerbation rate was analyzed using a negative binomial model, and a mixed-effect model was used to analyze changes in forced expiratory volume in 1 second and asthma control test score over time.

RESULTS

A total of 141 patients with SEA were included in the analysis; 71 (50%) received dupilumab; 40 (28%) received reslizumab, and 30 (21%) received mepolizumab. During the 12-month follow-up, 27.5%, 43.3%, and 38.0% of patients in the reslizumab, mepolizumab, and dupilumab groups, respectively, experienced at least 1 exacerbation. However, after adjusting for confounding factors, the dupilumab and mepolizumab groups showed similar outcomes in time-to-first exacerbation, exacerbation rate, forced expiratory volume in 1 second, and asthma control test score to those of the reslizumab group.

CONCLUSION

In patients with SEA, treatment with reslizumab, mepolizumab, and dupilumab resulted in comparable clinical outcomes within a 12-month period.

TRIAL REGISTRATION

The cohort protocol was sanctioned by the Institutional Review Board of each study center (clinicaltrial.gov identifier NCT05164939).

Decoding treatment efficacy: uncovering response and failure dynamics to biologics in asthma

INTRODUCTION

Asthma is a global health problem, with alarming prevalence and mortality rates. Biologic therapies, particularly monoclonal antibodies such as omalizumab, have emerged as promising alternatives, targeting specific immune pathways. This article assesses the efficacy of these biologics in asthma management and attempts to reveal factors associated with their response and failure dynamics.

AREA COVERED

This article explores the efficacy of biologics in asthma, biomarkers, and the relationship between asthma phenotypes (including eosinophilic and non-eosinophilic (neutrophilic) types) and biologic treatments; particularly their effectiveness for each subtype.

EXPERT OPINION

Personalized asthma management that incorporates molecular insights as well as individual variations is of outmost necessity. An emphasis is put on immunological profiling, understanding comorbidities and considering individual patient factors when managing asthma. Cutting-edge phenotyping tools including omic technologies play a crucial role in improving asthma management precision. Variability in patient responses to biologic treatments such as non-responders, partial responders and super responders poses a formidable challenge to effective asthma care management strategies.

Biologics in severe asthma: A pragmatic approach for choosing the right treatment for the right patient

The development of monoclonal antibody therapies targeting specific components of the pathways relevant to asthma pathophysiology has revolutionized treatment of severe asthma both in adults and children and helped to further unravel the heterogeneity of this disease. However, the availability of multiple agents, often with overlapping eligibility criteria, creates a need for pragmatic guidance for specialists undertaking care of patients with severe asthma. In this review, we provide an overview of the data supporting the clinical efficacy of biologics in distinct asthma phenotypes/endotypes. We also focus on the role of biomarkers and treatable traits, including comorbidities, in the choice of asthma biologics, highlight which treatments have been demonstrated to be steroid sparing in corticosteroid dependent asthma, and provide practical guidance that can drive shared decision making on treatment choice with patients. In addition, we summarize what is known to date regarding long-term safety of these drugs, and lastly, discuss future directions in biologics research.

WITHDRAWN: Prospective direct comparison of biological treatments on severe eosinophilic asthma: Findings from the PRISM study

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The clinical efficacy of type 2 monoclonal antibodies in eosinophil-associated chronic airway diseases: a meta-analysis

Background

Anti-type 2 inflammation therapy has been proposed as a treatment strategy for eosinophil-associated chronic airway disorders that could reduce exacerbations and improve lung function. We performed a meta-analysis of randomized controlled trials to assess the effectiveness of type 2 monoclonal antibodies (anti-T2s) for eosinophil-associated chronic airway disorders.

Methods

PubMed, Embase, Web of Science, and Cochrane Library were searched from their inception to 21 August 2022. Randomized clinical trials evaluating the effectiveness of anti-T2s versus placebo in the treatment of chronic airway diseases were selected. The outcomes were exacerbation rate and change in pre-bronchodilator forced expiratory volume in 1 s (FEV1) from baseline. The Cochrane Risk of Bias Assessment Tool 1.0 was used to evaluate the risk of bias, and the random-effects or fixed-effect model were used to pool the data.

Results

Thirty-eight articles concerning forty-one randomized clinical trials with 17,115 patients were included. Compared with placebo, anti-T2s therapy yielded a significant reduction in exacerbation rate in COPD and asthma (Rate Ratio (RR)=0.89, 95%CI, 0.83-0.95, I2 = 29.4%; RR= 0.59, 95%CI, 0.52-0.68, I2 = 83.9%, respectively) and improvement in FEV1 in asthma (Standard Mean Difference (SMD)=0.09, 95%CI, 0.08-0.11, I2 = 42.6%). Anti-T2s therapy had no effect on FEV1 improvement in COPD (SMD=0.05, 95%CI, -0.01-0.10, I2 = 69.8%).

Conclusion

Despite inconsistent findings across trials, anti-T2s had a positive overall impact on patients' exacerbation rate in asthma and COPD and FEV1 in asthma. Anti-T2s may be effective in treating chronic airway illnesses related to eosinophils.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022362280.

Uncontrolled severe T2 asthma: Which biological to choose? A biomarker-based approach

In recent years, advances in knowledge of molecular mechanisms involved in asthma have changed uncontrolled severe asthma (USA) treatment, with the appearance of biological treatment. USA is a heterogeneous entity with different endotypes and phenotypes. Nowadays, the biological drugs approved with asthma indication are omalizumab, mepolizumab, reslizumab, benralizumab and dupilumab. Tezepelumab is approved by the Food and Drug Administration (FDA) in the United States and, recently, by the European Medicines Agency (EMA). All these biological drugs have shown their efficacy in clinical trials, especially in reducing exacerbations, improving asthma control, quality of life, pulmonary function, and withdrawing systemic corticosteroids or at least reducing their daily dose, with some differences between them. Except for mepolizumab and reslizumab, biological drugs have different targets and thus different therapeutic indications should be expected; however, in some patients, more than one drug could be indicated, making the election more difficult. Because there are no direct comparisons between biological drugs, some biomarkers are used to choose between them, but they are not unbeatable. In this article, an algorithm to choose the first biological drug in a specific patient is proposed based on different study results and patient' characteristics.

Comparative efficacy of mepolizumab, benralizumab, and dupilumab in eosinophilic asthma: A Bayesian network meta-analysis

BACKGROUND

The comparative safety and efficacy of the biologics currently approved for asthma are unclear.

OBJECTIVE

We compared the safety and efficacy of mepolizumab, benralizumab, and dupilumab in individuals with severe eosinophilic asthma.

METHODS

We performed a systematic review of peer-reviewed literature published 2000 to 2021. We studied Bayesian network meta-analyses of exacerbation rates, prebronchodilator FEV1, the Asthma Control Questionnaire, and serious adverse events in individuals with eosinophilic asthma.

RESULTS

Eight randomized clinical trials (n = 6461) were identified. We found in individuals with eosinophils ≥300 cells/μL the following: in reducing exacerbation rates compared to placebo: dupilumab (risk ratio [RR], 0.32; 95% credible interval [CI], 0.23 to 0.45), mepolizumab (RR, 0.37; 95% CI, 0.30 to 0.45), and benralizumab (RR, 0.49; 95% CI, 0.43 to 0.55); in improving FEV1: dupilumab (mean difference in milliliters [MD] 230; 95% CI, 160 to 300), benralizumab (MD, 150; 95% CI, 100 to 200), and mepolizumab (MD, 150; 95% CI, 66 to 220); and in reducing Asthma Control Questionnaire scores: mepolizumab (MD, -0.63; 95% CI, -0.81 to -0.45), dupilumab (MD, -0.48; 95% CI, -0.83 to -0.14), and benralizumab (MD, -0.32; 95% CI, -0.43 to -0.21). In individuals with eosinophils 150-299 cells/μL, benralizumab (RR, 0.62; 95% CI, 0.52 to 0.73) and dupilumab (RR, 0.60; 95% CI, 0.38 to 0.95) were associated with lower exacerbation rates; and only benralizumab (MD, 81; 95% CI, 8 to 150) significantly improved FEV1. These differences were minimal compared to clinically important thresholds. For serious adverse events in the overall population, mepolizumab (odds ratio, 0.67; 95% CI, 0.48 to 0.92) and benralizumab (odds ratio, 0.74; 95% CI, 0.59 to 0.93) were associated with lower odds of a serious adverse event, while dupilumab was not different from placebo (odds ratio, 1.0; 95% CI, 0.74 to 1.4).

CONCLUSION

There are minimal differences in the efficacy and safety of mepolizumab, benralizumab, and dupilumab in eosinophilic asthma.

Cochrane Airways Group, Crossingham I, Richardson R, Hinks TSC, Spencer S, Couillard S, Maynard-Paquette AC, Thomassen D, Howell I. Biologics for chronic severe asthma: a network meta‐analysis

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To evaluate the benefits and harms of biological agents targeting type‐2 inflammation (benralizumab, dupilumab, mepolizumab, omalizumab, reslizumab, tezepelumab) in people with severe asthma, with a network meta‐analysis and to rank agents by effectiveness.

Anti-IL-5 therapies for asthma

BACKGROUND

This is the second update of previously published reviews in the Cochrane Library (2015, first update 2017). Interleukin-5 (IL-5) is the main cytokine involved in the proliferation, maturation, activation and survival of eosinophils, which cause airway inflammation and are a classic feature of asthma. Studies of monoclonal antibodies targeting IL-5 or its receptor (IL-5R) suggest they reduce asthma exacerbations, improve health-related quality of life (HRQoL) and lung function in appropriately selected patients, justifying their inclusion in the latest guidelines.

OBJECTIVES

To compare the effects of therapies targeting IL-5 signalling (anti-IL-5 or anti-IL-5Rα) with placebo on exacerbations, health-related quality-of-life (HRQoL) measures and lung function in adults and children with chronic asthma, and specifically in those with eosinophilic asthma refractory to existing treatments.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and two trials registers, manufacturers' websites, and reference lists of included studies. The most recent search was 7 February 2022.

SELECTION CRITERIA

We included randomised controlled trials comparing mepolizumab, reslizumab and benralizumab versus placebo in adults and children with asthma.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and analysed outcomes using a random-effects model. We used standard methods expected by Cochrane.

MAIN RESULTS

Seventeen studies on about 7600 participants met the inclusion criteria. Six used mepolizumab, five used reslizumab, and six used benralizumab. One study using benralizumab was terminated early due to sponsor decision and contributed no data. The studies were predominantly on people with severe eosinophilic asthma, which was similarly but variably defined. One was in children aged 6 to 17 years; nine others included children over 12 years but did not report results by age group separately. We deemed the overall risk of bias to be low, with all studies contributing data of robust methodology. We considered the certainty of the evidence for all comparisons to be high overall using the GRADE scheme, except for intravenous (IV) mepolizumab and subcutaneous (SC) reslizumab because these are not currently licensed delivery routes. The anti-IL-5 treatments assessed reduced rates of 'clinically significant' asthma exacerbation (defined by treatment with systemic corticosteroids for three days or more) by approximately half in participants with severe eosinophilic asthma on standard care (at least medium-dose inhaled corticosteroids (ICS)) with poorly controlled disease (either two or more exacerbations in the preceding year or Asthma Control Questionnaire (ACQ) score of 1.5 or more), except for reslizumab SC. The rate ratios for these effects were 0.45 (95% confidence interval (CI) 0.36 to 0.55; high-certainty evidence) for mepolizumab SC, 0.53 (95% CI 0.44 to 0.64; moderate-certainty evidence) for mepolizumab IV, 0.43 (95% CI 0.33 to 0.55; high-certainty evidence) for reslizumab IV, and 0.59 (95% CI 0.52 to 0.66; high-certainty evidence) for benralizumab SC. Non-eosinophilic participants treated with benralizumab also showed a significant reduction in exacerbation rates, an effect not seen with reslizumab IV, albeit in only one study. No data were available for non-eosinophilic participants treated with mepolizumab. There were improvements in validated HRQoL scores with all anti-IL-5 agents in severe eosinophilic asthma. This met the minimum clinically important difference (MCID) for the broader St. George's Respiratory Questionnaire (SGRQ; 4-point change) for benralizumab only, but the improvement in the ACQ and Asthma Quality of Life Questionnaire (AQLQ), which focus on asthma symptoms, fell short of the MCID (0.5 point change for both ACQ and AQLQ) for all of the interventions. The evidence for an improvement in HRQoL scores in non-eosinophilic participants treated with benralizumab and reslizumab was weak, but the tests for subgroup difference were negative. All anti-IL-5 treatments produced small improvements in mean pre-bronchodilator forced expiratory flow in one second (FEV1) of between 0.08 L and 0.15 L in eosinophilic participants, which may not be sufficient to be detected by patients. There were no excess serious adverse events with any anti-IL-5 treatment; in fact, there was a reduction in such events with benralizumab, likely arising from fewer asthma-related hospital admissions. There was no difference compared to placebo in adverse events leading to discontinuation with mepolizumab or reslizumab, but significantly more discontinued benralizumab than placebo, although the absolute numbers were small (42/2026 (2.1%) benralizumab versus 11/1227 (0.9%) placebo). The implications for efficacy or adverse events are unclear.

AUTHORS' CONCLUSIONS

Overall this analysis supports the use of anti-IL-5 treatments as an adjunct to standard care in people with severe eosinophilic asthma and poor symptom control. These treatments roughly halve the rate of asthma exacerbations in this population. There is limited evidence for improved HRQoL scores and lung function, which may not meet clinically detectable levels. The studies did not report safety concerns for mepolizumab or reslizumab, or any excess serious adverse events with benralizumab, although there remains a question over adverse events significant enough to prompt discontinuation. Further research is needed on biomarkers for assessing treatment response, optimal duration and long-term effects of treatment, risk of relapse on withdrawal, non-eosinophilic patients, children (particularly under 12 years), comparing anti-IL-5 treatments to each other and, in patients meeting relevant eligibility criteria, to other biological (monoclonal antibody) therapies. For benralizumab, future studies should closely monitor rates of adverse events prompting discontinuation.

The Clinical Efficacy of Type 2 Inflammation-Specific Agents Targeting Interleukins in Reducing Exacerbations in Severe Asthma: A Meta-Analysis

PURPOSE

Monoclonal antibodies against type 2 inflammatory pathways are currently promising therapeutics for severe asthma. The aim of this study was to determine how well type 2 (T2) inflammation-specific agents targeting interleukins reduce the rate of asthma exacerbations (AE) in patients with severe asthma.

MATERIALS AND METHODS

We performed a systematic review and meta-analysis in accordance with PRISMA guidelines. A systematic literature search was conducted in PubMed, Embase, and the Cochrane Central Register. The primary outcome was the reduction rate of annualized AEs.

RESULTS

We analyzed 17 studies comprising 11800 subjects. A total of 6197 patients received T2-specific agents (benralizumab, dupilumab, lebrikizumab, mepolizumab, reslizumab, and tralokinumab). Overall, T2-specific agents were significantly associated with a lower risk of AE, compared with placebo [rate ratio (RR) 0.58, 95% confidence interval (CI) 0.51 to 0.66]. Among all studied agents, only tralokinumab did not demonstrate a reduction in AE. The efficacy of T2-specific agents in reducing AE was maintained regardless of the pathway used. A subgroup analysis indicated that T2-specific agents further reduced the risk of AE in patients with eosinophil counts of ≥300 cells/µL (RR 0.41, 95% CI 0.32 to 0.53).

CONCLUSION

Our findings suggest that T2-specific agents are significantly associated with a reduced rate of AE, compared with placebo. Their efficacy appears to be enhanced in patients with eosinophil counts of ≥300 cells/µL.

The new era of add-on asthma treatments: where do we stand?

Globally, a small proportion (5-12%) of asthma patients are estimated to have severe disease. However, severe asthma accounts for disproportionately high healthcare resource utilization. The Global Initiative for Asthma (GINA) management committee recommends treating patients with asthma with inhaled corticosteroids plus long-acting β2-agonists and, when needed, adding a long-acting muscarinic receptor antagonist or biologic agent. Five biologics, targeting different effectors in the type 2 inflammatory pathway, are approved for asthma treatment. However, biologics have not been compared against each other or add-on inhaled therapies in head-to-head clinical trials. As a result, their positioning versus that of current and anticipated small-molecule strategies is largely unknown. Furthermore, with the emergence of biomarkers for predicting response to biologics, a more personalized treatment approach-currently lacking with inhaled therapies-may be possible. To gain perspective, we reviewed recent advances in asthma pathophysiology, phenotypes, and biomarkers; the place of biologics in the management and personalized treatment of severe asthma; and the future of biologics and small-molecule drugs. We propose an algorithm for the stepwise treatment of severe asthma based on recommendations in the GINA strategy document that accounts for the broad range of phenotypes targeted by inhaled therapies and the specificity of biologics. In the future, both biologics and small molecules will continue to play key roles in the individualized treatment of severe asthma. However, as targeted therapies, their application will continue to be focused on patients with certain phenotypes who meet the specific criteria for use as identified in pivotal clinical trials.

Comparative Efficacy and Safety of Tezepelumab and Other Biologics in Patients with Inadequately Controlled Asthma According to Thresholds of Type 2 Inflammatory Biomarkers: A Systematic Review and Network Meta-Analysis

The anti-thymic stromal lymphopoietin antibody (tezepelumab) has therapeutical potential for inadequately controlled asthma. However, evidence comparing tezepelumab with other biologics is scarce. To address this issue, we performed a network meta-analysis to compare and rank the efficacy of five treatments (tezepelumab, dupilumab, benralizumab, mepolizumab, and placebo) in overall participants and in subgroups stratified by the thresholds of type 2 inflammatory biomarkers, including peripheral blood eosinophil count (PBEC) and fractional exhaled nitric oxide (FeNO). The primary endpoints were annualized exacerbation rate (AER) and any adverse events (AAEs). In the ranking assessment using surface under the cumulative ranking curve (SUCRA) of AER, tezepelumab ranked the highest overall and across subgroups (based on PBEC and FeNO level thresholds). A significant difference was observed between tezepelumab and dupilumab in the patient subgroup with PBEC < 150, and between tezepelumab and benralizumab in overall participants and the patient subgroup with PBEC ≥ 300 and ≥150, respectively. There was no significant difference in the incidence of AAEs in the overall participants between each pair of five treatment arms. These results provide a basis for the development of treatment strategies for asthma and may guide basic, clinical, or translational research.

Controversies in Allergy: Choosing a Biologic for Patients with Severe Asthma

The availability of a range of new biological treatments targeting type-2 inflammation has provided new opportunities for patients with more severe asthma. Treatment has a bigger effect on exacerbations than day-to-day symptoms, and efficacy increases with increasing intensity of type-2 airway inflammation as reflected by the blood eosinophil count and fractional exhaled nitric oxide. The similarity of the clinical effects and target populations coupled with the absence of direct head-to-head comparative data makes it difficult to choose the right biologic for a given patient. In this review, we summarize the key efficacy data from phase 3 trials; discuss indirect comparisons; review clinical and laboratory variables that may be associated with a differential response to treatment; outline practical considerations that might be important to individual patients; and suggest an algorithm for choosing the most appropriate biologic to start with and the first choice to switch to.

Effectiveness of Switching Biologics for Severe Asthma Patients in Japan: A Single-Center Retrospective Study

BACKGROUND

In Japan, biologic therapy was initiated for patients with severe asthma in 2009. In recent years, four biologics with different mechanisms of action have become available in the clinical setting. However, the efficacy of switching between biologics remains uncertain.

METHODS

To elucidate the efficacy of switching between biologics, 97 patients were enrolled who had received any biologic therapy for severe asthma at Jikei University Hospital, Tokyo, Japan, from July 2009 to December 2020. We retrospectively examined the patient characteristics, biomarkers, pulmonary function test results, selected biologics, and efficacy.

RESULTS

Thirty-one males and 66 females received any biologics. The mean age was 53.3 years at the initiation of biologic therapy. Initially, 33, 41, 15 and eight patients received omalizumab, mepolizumab, benralizumab, and dupilumab, respectively. Among three representative indicators for biologics administration, the peripheral blood eosinophil count, serum IgE levels and fractional exhaled nitric oxide, 64% of the patients had two indicators, and 28% had three indicators. Thirty-four patients (35%) switched from the initial biologic to another, and the reasons for switching included persistent asthmatic symptoms (n=22), schedule of hospital visits (n=5), and other reasons. Thus, the treatment was effective in 11 patients after switching. In addition, two patients received combination therapy with different biologics. Eighteen patients (19%) interrupted treatment for various reasons. Regardless of whether the biologic was the initial therapy, the overall efficacy of the four biologics was 60% based on the global evaluation of treatment effectiveness.

CONCLUSION

Switching between biologics can be a promising option for severe asthma patients in whom treatment with an initial biologic is ineffective.

How to Assess Effectiveness of Biologics for Asthma and What Steps to Take When There Is Not Benefit

Five biologic medications are approved in the United States for the treatment of asthma that is not well controlled with other therapies. All target asthma with elevated type 2 inflammatory markers, such as elevated eosinophils, fractional exhaled nitric oxide, or total and specific IgE. Asthma severity, phenotype, age, biomarkers, treatment goals/outcomes, comorbid conditions, safety, and cost should all help guide the initial biologic choice. In addition, a shared decision-making process with the patient is needed to optimize adherence, with special attention to patient preference regarding outcomes, safety concerns, and medication administration options. After a biologic agent is initiated, sufficient time is needed to monitor efficacy and response. For patients who do not respond favorably, patient-, disease-, and medication-related factors should be considered and remedied, if possible. Persistent suboptimal responders necessitate a reexamination of asthma phenotype, biomarkers, and the suspected immune response pathways. For some patients, a change in biologic therapy or other therapeutic options may be warranted. In this review, we examine the clinical approach for choosing an initial biologic for the treatment of asthma, the assessment of response to biologics, and the process of troubleshooting and adjusting biologic treatment for those patients with suboptimal responses.

Severe asthma: adding new evidence - Latin American Thoracic Society

This document constitutes a summary of the clinical practice guidelines (CPGs) prepared at the initiative of the Latin American Thoracic Society (ALAT). Due to new evidence in the treatment of severe asthma, it was agreed to select six clinical questions, and the corresponding recommendations are provided herein. After considering the quality of the evidence, the balance between desirable and undesirable impacts and the feasibility and acceptance of procedures, the following recommendations were established. 1) We do not recommend the use of an inhaled corticosteroid (ICS) plus formoterol as rescue medication in the treatment of severe asthma. 2) We suggest performing many more high-quality randomised studies to evaluate the efficacy and safety of tiotropium in patients with severe asthma. 3) Omalizumab is recommended in patients with severe uncontrolled allergic asthma with serum IgE levels above 30 IU. 4) Anti-interleukin (IL)-5 drugs are recommended in patients with severe uncontrolled eosinophilic asthma (cut-off values above 150 cells·µL⁻¹ for mepolizumab and above 400 cells·µL⁻¹ for reslizumab). 5) Benralizumab is recommended in adult patients with severe uncontrolled eosinophilic asthma (cut-off values above 300 cells·µL⁻¹). 6) Dupilumab is recommended in adult patients with severe uncontrolled allergic and eosinophilic asthma and in adult patients with severe corticosteroid-dependent asthma.

Severe #asthma: evidence @ALAToraxhttps://bit.ly/34jYhg2

Beliefs and preferences regarding biological treatments for severe asthma

Background

Severe asthma is a serious condition with a significant burden on patients' morbidity, mortality, and quality of life. Some biological therapies targeting the IgE and interleukin-5 (IL5) mediated pathways are now available. Due to the lack of direct comparison studies, the choice of which medication to use varies. We aimed to explore the beliefs and practices in the use of biological therapies in severe asthma, hypothesizing that differences will occur depending on the prescribers’ specialty and experience.

Methods

We conducted an online survey composed of 35 questions in English. The survey was circulated via the INterasma Scientific Network (INESNET) platform as well as through social media. Responses from allergists and pulmonologists, both those with experience of prescribing omalizumab with (OMA/IL5) and without (OMA) experience with anti-IL5 drugs, were compared.

Results

Two hundred eighty-five (285) valid questionnaires from 37 countries were analyzed. Seventy-on percent (71%) of respondents prescribed biologics instead of oral glucocorticoids and believed that their side effects are inferior to those of Prednisone 5 mg daily. Agreement with ATS/ERS guidelines for identifying severe asthma patients was less than 50%. Specifically, significant differences were found comparing responses between allergists and pulmonologists (Chi-square test, p < 0.05) and between OMA/IL5 and OMA groups (p < 0.05).

Conclusions

Uncertainties and inconsistencies regarding the use of biological medications have been shown. The accuracy of prescribers to correctly identify asthma severity, according to guidelines criteria, is quite poor. Although a substantial majority of prescribers believe that biological drugs are safer than low dose long-term treatment with oral steroids, and that they must be used instead of oral steroids, every effort should be made to further increase awareness. Efficacy as disease modifiers, biomarkers for selecting responsive patients, timing for outcomes evaluation, and checks need to be addressed by further research. Practices and beliefs regarding the use of asthma biologics differ between the prescriber's specialty and experience; however, the latter seems more significant in determining beliefs and behavior. Tailored educational measures are needed to ensure research results are better integrated in daily practice.

Pharmacotherapeutic management of asthma in the elderly patient

INTRODUCTION

Asthma is a heterogeneous syndrome with variable phenotypes. Reversible airway obstruction and airway hyper-responsiveness often with an atopic or eosinophilic component is common in the elderly asthmatic. Asthma chronic obstructive pulmonary disease overlap syndrome (ACOS), a combination of atopy-mediated airway hyper-responsiveness and a history of smoking or other environmental noxious exposures, can lead to some fixed airway obstruction and is also common in elderly patients. Little specific data exist for the treating the elderly asthmatic, thus requiring the clinician to extrapolate from general adult data and asthma treatment guidelines.

AREAS COVERED

A stepwise approach to pharmacotherapy of the elderly patient with asthma and ACOS is offered and the literature supporting the use of each class of drugs reviewed.

EXPERT OPINION

Inhaled, long-acting bronchodilators in combination with inhaled corticosteroids represent the backbone of treatment for the elderly patient with asthma or ACOS . Beyond these medications used as direct bronchodilators and topical anti-inflammatory agents, a stepwise approach to escalation of therapy includes multiple options such as oral leukotriene receptor antagonist or 5-lipoxygense inhibitor therapy, oral phosphodiesterase inhibitors, systemic corticosteroids, oral macrolide antibiotics and if evidence of eosinophilic/atopic component disease exists then modifying monoclonal antibody therapies.

Monoclonal Antibody Therapy in Childhood Asthma

PURPOSE OF REVIEW

There has been an explosion of monoclonal antibodies in the treatment of severe uncontrolled adult asthma. Studies have now been published in severe pediatric asthma. There are numerous questions that need to be answered in determining whether these modalities are appropriate and safe in children.

RECENT FINDINGS

This is a narrative review examining the latest pediatric literature on monoclonal antibodies, both approved and in the pipeline, for uncontrolled asthma. Presently, all of the biologics are positioned to treat patients with underlying type 2 high disease. Two monoclonal antibodies are approved for children 6 years of age and older, omalizumab and mepolizumab, with more likely approved in the near future. The effect of these agents in controlling severe pediatric asthma is promising. Data is limited to long-term efficacy and safety, and whether any agent has an effect on the natural history of asthma.

Dupilumab: A Review in Moderate to Severe Asthma

Dupilumab (Dupixent^®) is a fully human monoclonal antibody against the interleukin (IL)-4 receptor α subunit of IL-4 and IL-4/IL-13 receptor complexes. IL-4 and IL-13 are key cytokines in driving type 2 inflammation, a dominant and largely eosinophilic inflammatory pathway in asthma. Trials evaluating the efficacy of dupilumab in asthma include three pivotal, placebo-controlled, phase 3 or 2b trials of 24-52 weeks' treatment duration in patients aged ≥ 12 years with moderate-to-severe asthma (inadequately controlled with medium-to-high dose inhaled corticosteroids) or severe asthma [dependent on oral corticosteroids (OCS) for control]. In these studies, adding subcutaneous dupilumab (200 or 300 mg every 2 weeks) to background therapy was generally well tolerated and reduced the rate of severe asthma exacerbations, improved lung function, as well as asthma control and, where specified, health-related quality of life (HR-QOL), and enabled OCS maintenance doses to be reduced without impacting asthma control. Dupilumab displayed efficacy across various patient subgroups, although those with heightened type 2 immune activity, including elevated eosinophils and fractional exhaled nitric oxide, tended to have a more prominent treatment benefit. Dupilumab is consequently widely indicated (and a valuable treatment option) as an add-on therapy in patients aged ≥ 12 years who have severe/moderate-to-severe asthma with a type 2 inflammation/eosinophilic phenotype despite conventional treatments or have OCS-dependent asthma.

Combined IMIG and Immune Ig Attenuate Allergic Responses in Beagle Dogs

Background

We previously reported attenuation of serum OVA-specific IgE levels and of lymphocyte-derived IL-4, both nominal markers of allergic immunity, following injection of a combination of homologous (mouse) polyclonal anti-idiotypic immunoglobulin (Ig) and immune Ig in BALB/c mice. We predicted this might generalize to other species and using heterologous mixtures of Igs. This was assessed in mice using OVA sensitization in the presence of human Igs as a source of both anti-idiotype Ig and immune Ig and in dogs with peanut butter-induced allergic responses.

Methods

Eight-week-old BALB/c mice received OVA immunization and 5 weekly injections of immune Ig or anti-idiotype Ig from either homologous (mouse) or heterologous (human) sources. Five-month-old Beagles received weekly topical exposure (on the abdomen) to peanut butter and treatment with pooled dog Ig and dog antirabies immune Ig, or a combination of human IMIG and human anti-Tet. All mice/dogs thereafter received a final allergen challenge, and serum IgG, IgE, and allergen-induced IL-2/IL-4 and IL-31 production in 72 hr cultures was measured.

Results

In mice attenuation of OVA-induced allergy (IgE-specific Ig and OVA-induced IL-4) was seen using both mouse and human Ig mixtures, without effect on OVA serum IgG or OVA-induced IL-2. Attenuation of concanavalin A- (ConA-) induced IL-4 : IL-2 production and of peanut butter-induced IL-4 and IL-31 was seen in dogs receiving combinations of both heterologous and homologous immune Igs and anti-idiotype Igs, with no decline in IL-2 production. Allergen-specific IgE/IgG was not detectable in dog serum, but there was a trend to lower total serum IgE levels (and decreased IgE : IgG ratios).

Conclusion

Homologous and heterologous combinations of polyclonal IMIG and immune Ig attenuate allergic responses in mice and dogs. This treatment protocol represents a novel approach which can be adapted for allergic desensitization in veterinary and human use.

Rubusoside alleviates the ovalbumin-induced mice allergic asthma by modulating the NF-κB activation

The anti-inflammatory and anti-asthmatic effects of rubusoside (Rbs) were investigated in the ovalbumin (OVA)-induced asthmatic mice, followed by effective attenuation of Rbs treatment on the airway hyperresponsiveness and reduction of inflammatory cells inside the bronchoalveolar lavage fluid (BALF). The mitigation of inflammatory infiltration as a result of Rbs treatment was histologically observed in these mice lungs. Rbs contributed to the decrease of inflammatory cytokines (TNF-α, IL-13, IL-6, IL-5, and IL-4) inside the BALF of mice with asthma. A decline of OVA-dependent IgE and IgG1 inside the serum was also noticed in these mice. Rbs was proved to enhance the mRNA level of Foxp3 inside the mice lung affected with asthma while decrease that of IL-17A, IL-23, and RORγt. NF-κB pathway activation elicited by OVA was suppressed by Rbs inside the pulmonary tissues. Rbs played significantly in the reduction of airway inflammation induced by OVA which with modulating NF-κB pathway activation. PRACTICAL APPLICATIONS: Simultaneous therapy with medicine and food is strategically significant for disease prevention and treatment in traditional Chinese medicine. Rbs is a diterpene glycoside isolated from Rubus suavissimus. The anti-inflammatory and anti-asthmatic mechanism dependent of Rbs need further study clinically. The goal of current investigation is to explore the anti-inflammatory as well as anti-asthmatic activity of Rbs in mouse models of OVA-induced experimental allergic asthma. Results of the present study are scientifically supportive for the use of Rbs as an adjunctive reagent for clinical treatment of allergic asthma.

Persistence of Sinonasal Disease Despite Mepolizumab

The treatment paradigm for the management of chronic rhinosinusitis with nasal polyposis (CRSwNP) is currently undergoing a rapid evolution with the development of monoclonal antibody therapies targeted at type 2 inflammatory pathways. The use of these biologic therapies in asthmatic patients, and more recently, patients with CRSwNP has produced promising results, especially for patients with severe disease. Many questions regarding the appropriate timing of these medications, whether or not these new treatment strategies should be used as a monotherapy or in conjunction with traditional therapies such as sinus surgery, the role of appropriate phenotyping, and identification of biomarkers, remain unanswered. We herein present a case of a patient with severe eosinophilic asthma and comorbid CRSwNP who failed to achieve control of his respiratory symptomology and ultimately progressed to sinus surgery despite treatment with an anti-interleukin 5 monoclonal antibody therapy (mepolizumab). Consideration is given to the mechanistic underpinnings of the reported patient's failure. This case highlights the need for further understanding of the optimal usage of these novel therapeutics in the management of CRSwNP and in the need to better understand the pathophysiology of CRSwNP.

Effect of Anti-IL5, Anti-IL5R, Anti-IL13 Therapy on Asthma Exacerbations: A Network Meta-analysis

BACKGROUND

Several new treatments for severe asthma have become available in the last decade; yet, little data exist to guide their use in specific patient populations.

OBJECTIVE

A network meta-analysis was conducted comparing the efficacy of FDA-approved monoclonal antibody therapies in preventing exacerbations in patients with severe eosinophilic asthma.

METHODS

PubMed and Ovid were searched from inception until July 2019 for randomized controlled trials that studied the efficacy of benralizumab, dupilumab, mepolizumab, and reslizumab, in preventing acute exacerbations of asthma. Studies were included if they reported data for patients with severe eosinophilic asthma (defined in this meta-analysis as absolute eosinophil count ≥ 250 cells/μL). Annualized rate ratios for asthma exacerbations (during treatment) were calculated and converted to log rate ratios. Direct and indirect treatment estimates (for inter-drug differences) were analyzed using frequentist network meta-analysis methodology in R and treatments were ranked based on P-scores.

RESULTS

In total, nine studies were included in the final analysis. Network meta-analysis revealed that all drugs were superior to placebo in preventing rates of asthma exacerbation in the study population and no inter-drug differences existed. Dupilumab was found to have the greatest magnitudes of effect on decreasing log rate ratio of asthma exacerbation based on P-score (0.83).

CONCLUSION

Benralizumab, dupilumab, mepolizumab, and reslizumab are all associated with decreased asthma exacerbations in patients with eosinophilic asthma, with no significant inter-drug differences.

Mechanism(s) of prolonged attenuation of allergic responses after modulation of idiotypic regulatory network

BACKGROUND

We showed previously that allergic reactivity to ovalbumin (OVA) could be regulated in mice following perturbation of immune networks using combinations of an immune Ig along with anti-idiotypic Ig. We have explored features of this regulation including: its persistence after cessation of administration of combined Igs; the ability of heterologous Igs to produce immunoregulation; a role for Treg induction in regulation; and the ability to attenuate responses in mice pre-sensitized to an allergic stimulus.

METHODS

BALB/c mice were sensitized to OVA. Mice also received 5 weekly injections of immune Ig or anti-idiotype Ig (at separate sites) from either homologous (mouse) or heterologous (human) sources. In the latter case pooled IVIG (given IM, hence hereafter IMIG) was used as a source of anti-idiotype Ig, and human anti-Tet as immune Ig. Injections of the Ig were given from the time of OVA sensitization (to attenuate development of immunity), or after pre-sensitization of mice (to attenuate existing allergic responses). All mice were assayed for development of OVA-specific serum IgE and IgG, as well as the production of OVA-induced IL-2, IL-4, IL-13, IL-31 and IL-33 in splenocytes cultured for 72 h. In studies examining possible mechanism(s) responsible for inhibition of immunity mice received, in addition to the Ig treatments described, infusion of depleting anti-CD4, and/or anti-CD8 antibodies, or a mAb to TNFSFR25, known to expand Tregs implicated in regulation of Allo immunity.

RESULTS

Combinations of both heterologous and homologous immune Igs and anti-idiotype Igs attenuated OVA allergic responses in both naïve and pre-sensitized mice. This attenuation persisted in mice greater than 14 weeks after cessation of treatment with the Igs used. Finally, depletion of either CD4 or CD8 cells ameliorated the suppressive effect seen, while the combination of anti-CD4 and anti-CD8 essentially abolished suppression. Suppression was further enhanced by anti-TNFSFR25 mAb.

CONCLUSIONS

We conclude that the combine Ig treatment protocols used produced a long-lasting suppression of allergic immunity, even in pre-sensitized animals. The effects seem to depend upon induction and expansion of Tregs and represents a novel approach to treatment of allergic disease in humans and other animals.

Protective activity of mogroside V against ovalbumin-induced experimental allergic asthma in Kunming mice

We investigated the antiasthmatic effect of mogroside V (Mog V) in mice with ovalbumin (OVA)-induced asthma. Administration of Mog V effectively attenuated OVA-induced airway hyperresponsiveness and reduced the number of inflammatory cells in bronchoalveolar lavage fluid (BALF). Histological examination showed that Mog V reduced the inflammatory infiltration of the lungs in the asthmatic mice. ELISAs suggested that Mog V effectively decreased the levels of IL-4, IL-5, and IL-13 in BALF and serum levels of OVA-specific IgE and IgG1 in the asthmatic mice. A quantitative reverse-transcription PCR assay also indicated that Mog V decreased the mRNA levels of IL-17A, IL-23, and RORγt in the lungs of the asthmatic mice (the opposite effect on Foxp3 mRNA). Furthermore, Mog V significantly reduced the OVA-induced activation of NF-κB in the lungs. This study indicates that Mog V alleviates OVA-induced inflammation in airways, and this effect is associated with a reduction in NF-κB activation. PRACTICAL APPLICATIONS: A traditional Chinese medicine herb has been reported to have a strong curative effect on asthma in clinical practice. Siraitia grosvenorii is known in China as a functional food product with the ability to improve lung function. Mogroside V is a triterpene glycoside isolated from S. grosvenorii. Nonetheless, the antiasthmatic effect of mogroside V has not been evaluated yet. The aim of this study was to investigate the antiasthmatic activity of mogroside V in mice with chemically induced asthma. The data from this study will provide some scientific evidence supporting wider use of S. grosvenorii in functional foods.

CD45Rb-low effector T cells require IL-4 to induce IL-10 in FoxP3 Tregs and to protect mice from inflammation

CD4⁺ effector/memory T cells (Tem) represent a leading edge of the adaptive immune system responsible for protecting the body from infection, cancer, and other damaging processes. However, a subset of Tem cells with low expression of CD45Rb (Rb^LoTem) has been shown to suppress inflammation despite their effector surface phenotype and the lack of FoxP3 expression, the canonical transcription factor found in most regulatory T cells. In this report, we show that Rb^LoTem cells can suppress inflammation by influencing Treg behavior. Co-culturing activated Rb^LoTem and Tregs induced high expression of IL-10 in vitro, and conditioned media from Rb^LoTem cells induced IL-10 expression in FoxP3⁺ Tregs in vitro and in vivo, indicating that Rb^LoTem cells communicate with Tregs in a cell-contact independent fashion. Transcriptomic and multi-analyte Luminex data identified both IL-2 and IL-4 as potential mediators of Rb^LoTem-Treg communication, and antibody-mediated neutralization of either IL-4 or CD124 (IL-4Rα) prevented IL-10 induction in Tregs. Moreover, isolated Tregs cultured with recombinant IL-2 and IL-4 strongly induced IL-10 production. Using house dust mite (HDM)-induced airway inflammation as a model, we confirmed that the in vivo suppressive activity of Rb^LoTem cells was lost in IL-4-ablated Rb^LoTem cells. These data support a model in which Rb^LoTem cells communicate with Tregs using a combination of IL-2 and IL-4 to induce robust expression of IL-10 and suppression of inflammation.

Mouse models of severe asthma for evaluation of therapeutic cytokine targeting

Severe asthma is a heterogeneous inflammatory disease of the airways, which requires treatment with high-dose inhaled corticosteroids or their systemic administration, yet often remains uncontrolled despite this therapy. Over the past decades, research efforts into phenotyping of severe asthma and defining the pathological mechanisms of this disease were successful largely due to the development of appropriate animal models. Recent identification of distinct inflammatory patterns of severe asthma endotypes led to novel treatment approaches, including targeting specific cytokines or their receptors with neutralizing antibodies. Here we discuss how different experimental mouse models contributed to generation of clinically relevant findings concerning pathogenesis of severe asthma and to identification of potential targets for biologic therapy.