Mepolizumab versus placebo for asthma

A review of the pathophysiology and the role of ion channels on bronchial asthma

Asthma is one of the main non-communicable chronic diseases and affects a huge portion of the population. It is a multifactorial disease, classified into several phenotypes, being the allergic the most frequent. The pathophysiological mechanism of asthma involves a Th2-type immune response, with high concentrations of allergen-specific immunoglobulin E, eosinophilia, hyperreactivity and airway remodeling. These mechanisms are orchestrated by intracellular signaling from effector cells, such as lymphocytes and eosinophils. Ion channels play a fundamental role in maintaining the inflammatory response on asthma. In particular, transient receptor potential (TRP), stock-operated Ca2+ channels (SOCs), Ca2+-activated K+ channels (IKCa and BKCa), calcium-activated chloride channel (TMEM16A), cystic fibrosis transmembrane conductance regulator (CFTR), piezo-type mechanosensitive ion channel component 1 (PIEZO1) and purinergic P2X receptor (P2X). The recognition of the participation of these channels in the pathological process of asthma is important, as they become pharmacological targets for the discovery of new drugs and/or pharmacological tools that effectively help the pharmacotherapeutic follow-up of this disease, as well as the more specific mechanisms involved in worsening asthma.

The evolving landscape of immunotherapy for the treatment of allergic conditions

Allergic conditions, such as asthma, chronic urticaria, atopic dermatitis (AD), and eosinophilic esophagitis, have long been treated with oral and topical steroids which resulted in negative off-target effects. However, newer biologic medications are increasingly being developed and approved for treatment of these conditions. These medications have a variety of mechanisms of action to target pathophysiology specific to these diseases. As biologics become more targeted, fewer off-target effects are seen improving tolerability for patients as well as expanded options for treatment of these conditions. This review discusses monoclonal antibody therapies (omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab, tezepelumab, and tralokinumab) including their safety and use in asthma, chronic urticaria, AD, and eosinophilic esophagitis.

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.

Real-World Effectiveness of Mepolizumab in Severe Eosinophilic Asthma: A Systematic Review and Meta-analysis

PURPOSE

Mepolizumab is a human monoclonal antibody against interleukin 5 (IL-5) used to treat severe eosinophilic asthma. Several studies have evaluated the effectiveness of mepolizumab in the real world. We conducted a systematic review and meta-analysis in the context of heterogeneity among patients, clinicians, and treatment regimens to study the effectiveness of mepolizumab in the real world.

METHODS

We searched the PubMed and Embase databases for real-world studies on severe asthma treatment with mepolizumab as of June 30, 2020. Exacerbations, asthma-related hospitalizations, forced expiratory volume in 1 second (FEV₁), Asthma Control Questionnaire (ACQ) or Asthma Control Test (ACT), corticosteroid use, peripheral blood eosinophil counts, and the fraction of exhaled nitric oxide were selected as indicators to evaluate the effectiveness. Standardized mean differences by the Cohen method and mean differences were chosen as indicators of effect size. Cohen d values of 0.2, 0.5, and 0.8 are considered as small, medium, and large effects, respectively. We used the Dersimonian-Laird random-effect model to quantify pooled effectiveness estimates.

FINDINGS

A total of 1457 patients from 13 studies were included in this review. At all time points, mepolizumab was associated with reductions in exacerbations (2.92 and 2.73 events per patient per year fewer at 6 and 12 months, respectively) and hospitalizations (0.36 events per patient per year fewer at 12 months); improvements in asthma control (ACQ scores reductions of 1.32 and 1.03 at 6 and 12 months, respectively; ACT scores increase of 6.52 at 6-12 months); slight improvements in pulmonary function (FEV₁ increase of 0.23 L at 1-3 months and 6-12 months, respectively); reductions in oral corticosteroid use (9.02- and 7.68-mg decrease at 6 and 12 months, respectively); and reductions in peripheral blood eosinophil counts (decreases of 559.11 cells/μL and 599.17 cells/μL at 1-3 months and 6-12 months, respectively) and fraction of exhaled nitric oxide (13-ppb reduction at 6-12 months).

IMPLICATIONS

Our study suggests that mepolizumab is associated with improvements in several clinically meaningful real-world outcomes. This study is a supplement to and extension of the efficacy of randomized controlled trials of mepolizumab. (Clin Ther. 2021;XX:XXX-XXX) © 2021 Elsevier HS Journals, Inc.

Targeted therapy in eosinophilic chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a common and preventable airway disease causing significant worldwide mortality and morbidity. Lifetime exposure to tobacco smoking and environmental particles are the two major risk factors. Over recent decades, COPD has become a growing public health problem with an increase in incidence. COPD is defined by airflow limitation due to airway inflammation and small airway remodelling coupled to parenchymal lung destruction. Most patients exhibit neutrophil-predominant airway inflammation combined with an increase in macrophages and CD8⁺ T-cells. Asthma is a heterogeneous chronic inflammatory airway disease. The most studied subtype is type 2 (T2) high eosinophilic asthma, for which there are an increasing number of biologic agents developed. However, both asthma and COPD are complex and share common pathophysiological mechanisms. They are known as overlapping syndromes as approximately 40% of patients with COPD present an eosinophilic airway inflammation. Several studies suggest a putative role of eosinophilia in lung function decline and COPD exacerbation. Recently, pharmacological agents targeting eosinophilic traits in uncontrolled eosinophilic asthma, especially monoclonal antibodies directed against interleukins (IL-5, IL-4, IL-13) or their receptors, have shown promising results. This review examines data on the rationale for such biological agents and assesses efficacy in T2-endotype COPD patients.

Patients with severe COPD and eosinophilic inflammation experience uncontrolled symptoms despite optimal pharmaceutical treatment. The development of new biomarkers is needed for better phenotyping of patients to propose innovative targeted therapy.https://bit.ly/2KzWuNO

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

Advances in understanding and reducing the burden of severe asthma in children

Severe asthma in children is rare, accounting for only a small proportion of childhood asthma. After addressing modifiable factors such as adherence to treatment, comorbidities, and adverse exposures, children whose disease is not well controlled on high doses of medication form a heterogeneous group of severe asthma phenotypes. Over the past decade, considerable advances have been made in understanding the pathophysiology of severe therapy-resistant asthma in children. However, asthma attacks and hospital admissions are frequent and mortality is still unacceptably high. Strategies to modify the natural history of asthma, prevent severe exacerbations, and prevent lung function decline are needed. Mechanistic studies have led to the development of several biologics targeting type 2 inflammation. This growing pipeline has the potential to reduce the burden of severe asthma; however, detailed assessment and characterisation of each child with seemingly severe asthma is necessary so that the most effective and appropriate management strategy can be implemented. Risk stratification, remote monitoring, and the integration of multiple data sources could help to tailor management for the individual child with severe asthma.

Human(ized) monoclonal antibodies in atopic patients - state of the art

Asthma is an important chronic disease affecting a lot of people worldwide. Treatment options for asthma like biological agents are being developed more frequently nowadays. Despite a lot of treatment options, some patients still remain symptomatic. As more and more practitioners choose treatment with biologic agents as a convenient way of therapy, biologic agents and other valuable methods must be discovered in order to cope with a growing number of treatment agents. This manuscript emphasizes on new generation monoclonal human(ized) antibodies in asthmatics and off-label use . The first developed biologic agent is the anti-immunoglobulin E monoclonal antibody called omalizumab. Currently it is an approved treatment option for asthma.

Asthma biologics: Comparing trial designs, patient cohorts and study results

OBJECTIVE

Five biologic therapies have FDA-approved indications for difficult-to-control asthma. The clinical trials that proved the efficacy and safety of these biologics were often similar in their inclusion criteria, study designs, and endpoints. Many of these trials have been reanalyzed post hoc to identify subsets of subjects considered to be enhanced responders. As a result, keeping up with the literature and deciding on the most appropriate biologic for our patients has become increasingly difficult. This review summarizes and compares trial designs, patient cohorts, and study results of the major trials involving these therapies.

DATA SOURCES

Included are basic science articles, online Food and Drug Administration (FDA) applications, and all the published reports of phase II and phase III clinical trials for FDA-approved asthma biologics.

STUDY SELECTIONS

Included are the major phase II and phase III clinical trials of 5 asthma biologics.

RESULTS

Because of variations in inclusion criteria and natural variations in enrolled cohorts, the baseline clinical traits and severity of study populations in asthma biologic trials differed significantly, which is important because baseline annualized exacerbation rates and blood eosinophilia are both strong predictors of a biologic's success. Notwithstanding, the trial results, when considered together, can help guide care providers in choosing the most appropriate biologic for our patients.

CONCLUSION

Understanding the details and differences in asthma biologic trial designs, patient cohorts, and in study results will help care providers make more informed decisions when choosing a biologic. We are hopeful this review will serve as a reference to care providers for this purpose.

Anti-IL-5 Biologicals Targeting Severe Late Onset Eosinophilic Asthma

Improved knowledge about the pathogenesis of asthma has facilitated the development of novel drugs and provided hope for patients with severe asthma. After the short- and long-term success of omalizumab in severe allergic phenotype, researchers have targeted patients with severe eosinophilic asthma who comprise up to 45% of adult severe asthma. Interleukin (IL)-5 and IL-5 receptor subunit α play crucial roles in the development, maturation, and operation of eosinophils. Currently, patients treated with anti-IL-5 biologicals depleting eosinophils experience the positive efficacy of these drugs, especially with regard to the reduction of exacerbation rate. The aim of this review was to shed light on severe eosinophilic asthma treatment with these new currently available agents selectively targeting IL-5 or its receptor, discussing their usage including pre-treatment concerns, such as selecting the target population and choosing the right agent among them, and subsequent assessment of relevant effect and safety issues.

An evaluation of mepolizumab for the treatment of severe asthma

Introduction: Asthma is considered one of the most common chronic conditions globally, characterized by variable airflow obstruction and symptoms. Severe asthma is diagnosed when asthma control requires high-intensity therapy or continues to remain uncontrolled despite treatment. Eosinophilic inflammation is known to be perpetuated by the activity of IL-5 in a proportion of severe asthma subjects, and targeting IL-5 may offer a therapeutic option. Areas covered: In this review, we discuss the role and pathogenesis of IL-5 and eosinophils in asthma and rationale of antagonizing IL-5 in severe eosinophilic asthma. Mepolizumab is the first of three anti-IL-5 biologics licensed in 2015 for use in this subgroup of patients. We discuss clinical and real-life studies leading up to its approval and post-marketing outcomes in terms of efficacy and safety to-date, as well as its pros and cons. Expert opinion: IL-5 antagonism has paved the way for an additional personalized therapeutic opportunity for use in severe asthma with eosinophilic inflammation, though there is limited evidence on the long-term implications of suppressing/depleting eosinophils and the duration for which they should be administered.

Mepolizumab in the management of severe eosinophilic asthma in adults: current evidence and practical experience

Asthma is a chronic inflammatory condition involving the airways with varying pathophysiological mechanisms, clinical symptoms and outcomes, generally controlled by conventional therapies including inhaled corticosteroids and long-acting β₂ agonists. However, these therapies are unable to successfully control symptoms in about 5–10% of severe asthma patients. Atopic asthma, characterized by high immunoglobulin (Ig)E or eosinophilia, represents about 50% of asthmatic patients. Interleukin (IL)-5 is the main cytokine responsible of activation of eosinophils, hence therapeutic strategies have been investigated and developed for clinical use. Biologics targeting IL-5 and its receptor (first mepolizumab and subsequently, reslizumab and benralizumab), have been recently approved and used as add-on therapy for severe eosinophilic asthma resulting in a reduction in the circulating eosinophil count, improvement in lung function and exacerbation reduction in asthma patients. Despite these biologics having been approved for stratified severe asthma patients that remain uncontrolled with high doses of conventional therapy, a number of patients may be eligible for more than one biologic. Presently, the lack of head-to-head studies comparing the biological agents among themselves and with conventional therapy make the choice of optimal therapy for each patient a challenge for clinicians. Moreover, discontinuation of these treatments, implications for efficacy or adverse events, in particular in long-term treatment, and needs for useful biomarkers are still matters of debate. In this review we evaluate to date, the evidence on mepolizumab that seems to demonstrate it is a well-tolerated and efficacious regimen for use in severe eosinophilic asthma, though more studies are still required.

Precision medicine in COPD: review of mepolizumab for eosinophilic COPD

Mepolizumab can reduce exacerbation rates in those with frequently exacerbating, severe COPD and raised blood eosinophils; this represents a further advance in precision medicine for COPD and targeted therapies http://ow.ly/uklu30m4YcU.

Anti-interleukin 5 Therapy for Eosinophilic Asthma: a Meta-analysis of Randomized Clinical Trials

Recently, more and more clinical trials have been performed to evaluate the effects of anti-interleukin (IL)-5 antibodies in eosinophilic asthma. However, a confirm conclusion has not been well established. We therefore sought to conduct a meta-analysis to assess the overall efficacy and safety of anti-interleukin 5 treatments in eosinophilic asthma. RCTs of anti-interleukin 5 treatments in eosinophilic asthma published up to June 2016 in PubMed, Embase, Cochrane library databases, and CBM, which reported pulmonary functions, quality-of-life scores, asthmatic exacerbations, and adverse events were included. Fixed-effect models were used to calculate mean difference, relative risks (RR), and 95 % CIs. Twelve studies involving 3340 patients were identified. Pooled analysis revealed significant improvements in FEV₁ (nine trials, 1935 subjects; MD = 0.12; 95 % CI, 0.08-0.16), and Asthma Quality-of-Life Questionnaire scores (five trials, 1334 subjects; MD = 0.23; 95 % CI, 0.13-0.34). Anti-interleukin 5 treatment was also associated with significantly decreased exacerbation risk than placebo (six trials, 875 subjects; RR = 0.52; 95 % CI, 0.46 to 0.59) and a lower incidence of adverse events (eight trials, 1754 subjects; RR = 0.93; 95 % CI, 0.89 to 0.97). Anti-interleukin 5 treatment is well tolerated and could significantly improve FEV₁, quality of life, and reduced exacerbations risk in patients with eosinophilic asthma. Further trials are necessary to assess the baseline blood eosinophil count to identify the optimal patients of eosinophilic asthma that could benefit from anti-interleukin 5 therapy.

Disconnect of type 2 biomarkers in severe asthma; dominated by FeNO as a predictor of exacerbations and periostin as predictor of reduced lung function

BACKGROUND

biomarkers of Type 2 (T2) inflammation may predict asthma control and exacerbation risk. However, the relationships between individual T2 biomarkers to exacerbations and lung function in severe asthma remain uncertain.

OBJECTIVES

to explore the roles played by T2 biomarkers individually and as a composite score in predicting clinical outcomes in severe asthma.

METHODS

unselected severe asthma patients were enrolled in this cross sectional real life study. Participants were clinically characterised and the following measurements were obtained: the frequency of exacerbations requiring oral corticosteroids (OCS), asthma control (Juniper ACQ6-7), lung function, Fraction exhaled Nitric Oxide (FeNO), peripheral blood eosinophils (PBE), and serum periostin.

RESULTS

A total of 115 patients were recruited [mean age 45 years (range 18-70), 80 (69.6%) females, mean forced expiratory volume in first second (FEV₁) %predicted was 68% ± 24.7, mean inhaled corticosteroids (ICS) 1.96 ± 0.82 mg/day. FeNO correlated significantly with PBE (r = 0.35, p = 0.0004), but not with periostin (r = 0.22, p = 0.065) and there was no significant correlation between PBE and periostin. FeNO correlation with exacerbations (r = 0.42, p = 0.0008) was stronger than PBE and periostin. A composite score of the 3 biomarkers correlated with exacerbations in a dose-dependent manner but multiple regression analysis did not confirm an added benefit. Only periostin demonstrated a significant correlation with FEV₁%predicted (r = -0.34, p = 0.004) with ROC-AUC 0.7.

CONCLUSION

FeNO demonstrated stronger correlation with asthma exacerbations than PBE or periostin with no definite added benefit from a composite score of the 3 biomarkers. Only periostin showed significant association with reduced lung function raising its potential as a biomarker of airway remodeling.

Type 2 immunity in asthma

Type 2-immunity represents the typical adaptive response to allergen exposure in atopic individuals. It mainly involves Th2 cells and immunoglobulin E, as the main orchestrators of type 2-inflammation. Recently, it has been highlighted that allergens may be responsible for a Th2 response beside specific IgE activation and that a number of other environmental stimuli, such as viruses and pollutants, can trigger the same pattern of inflammation beyond atopy. Emerging data sustain a substantial role of the so-called epithelial dysfunction in asthma pathogenesis, both from anatomic and functional point of view. Furthermore an increasing amount of evidence demonstrates the relevance of innate immunity in polarizing a Th2 impaired response in asthmatic patients. Under this perspective, the complex cross-talking between airway epithelium, innate and adaptive immunity is emerging as a major determinant of type 2-inflammation beyond allergens.

This review will include an update on the relevance of dysregulation of innate and adaptive type 2-immunity in asthma pathogenesis, particularly severe asthma, and on the role of the allergens that are associated with severe asthma. Type 2-immunity also will be reviewed in the light of the current and upcoming targeted treatments for severe asthma.

Astragalus Oral Solution Ameliorates Allergic Asthma in Children by Regulating Relative Contents of CD4+CD25highCD127low Treg Cells

Objective: To explore the effects of Astragalus oral solution (AOS) on allergic asthma in children by investigating relative contents of CD4⁺CD25^highCD127^low Treg cells. Methods: The contents of Astragaloside A in AOS were detected by using HPLC. Eighty children with allergic asthma were recruited from February 2016 to June 2017, and randomly assigned into the control group (received placebo, 0.1% quinine chloride in deionized water, daily) and the AOS group (received 10 mL AOS daily). After 6-month treatment, therapeutic results were compared between the two groups. Serum levels of IL-10 and TGF-beta, Th1 cytokines (IL-2 and IFN-γ), and Th2 cytokines (IL-4 and IL-6) were measured by using ELISA kits. Relative contents of CD4⁺CD25^highCD127^low Treg cells were determined by using flow cytometry. Results: Astragaloside A was the main ingredient of AOS with 0.216 ± 0.027 mg/mL from six-batch samples. After 6-month therapy, the AOS group showed improved forced expiratory volume in 1 s (FEV1) and the Pediatric Asthma Quality of Life Questionnaire (PAQLQ) scores compared with the control group (P < 0.05). Serum level of IL-10 was higher and the levels of TGF-beta, Th1 cytokines (IL-2 and IFN-γ), and Th2 cytokines (IL-4 and IL-6) were lower in the AOS group than in the control group (P < 0.05). AOS treatment increased the percentage of gated CD4⁺ T cells, CD4⁺CD25⁺ T cells, CD4⁺CD25^high Treg cells, CD4⁺CD25⁺FoxP3⁺ Treg cells and CD4⁺CD25^highCD127^low Treg cells when compared with the control group (P < 0.05). Conclusions: Astragaloside A was the main component of AOS, and AOS ameliorated allergic asthma in children by regulating relative contents of CD4⁺CD25^highCD127^low Treg cells.

Monoclonal Antibodies for the Management of Severe Asthma

Asthma is a heterogeneous inflammatory disease. Most patients respond to current standard of care, i.e., bronchodilators, inhaled glucocorticosteroids and other anti-inflammatory drugs, but in some adequate asthma control cannot be achieved with standard treatments. These difficult-to-treat patients would be the target population for new biological therapies. At present, omalizumab is the only biological agent approved for the treatment of early-onset, severe IgE-dependent asthma. It is safe, effective, and well tolerated. Also, discovery of asthma subtypes suggests new treatments. Half of patients with severe asthma have T-helper type 2 (Th-2) inflammation and they are expected to benefit from monoclonal antibody-based treatments. The efficacy of the investigational monoclonal antibody mepolizumab which targets IL-5 has been well documented in late onset non-atopic asthma with persistent eosinophilic airway inflammation. Anti-IL-4 and IL-13 agents (dupilumab, lebrikizumab, and tralokinumab) which block different Th-2 inflammatory pathways and agents targeting the Th-17 inflammatory pathway in severe refractory asthma are under development. In clinical trials, these drugs reduce disease activity and improve lung function, asthma symptoms, and quality of life. However, studies on larger groups of patients are needed to confirm their safety and efficacy.

Anti-IL5 therapies for asthma

BACKGROUND

This review is the first update of a previously published review in The Cochrane Library (Issue 7, 2015). Interleukin-5 (IL-5) is the main cytokine involved in the activation of eosinophils, which cause airway inflammation and are a classic feature of asthma. Monoclonal antibodies targeting IL-5 or its receptor (IL-5R) have been developed, with recent studies suggesting that they reduce asthma exacerbations, improve health-related quality of life (HRQoL) and lung function. These are being incorporated into asthma 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 qualify 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 the Cochrane Airways Trials Register, clinical trials registries, manufacturers' websites, and reference lists of included studies. The most recent search was March 2017.

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

MAIN RESULTS

Thirteen studies on 6000 participants met the inclusion criteria. Four used mepolizumab, four used reslizumab, and five used benralizumab. One study in 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. Eight included children over 12 years but these results were not reported separately. We deemed the risk of bias to be low, with all studies contributing data being of robust methodology. We considered the quality of the evidence for all comparisons to be high overall using the GRADE scheme, with the exception of intravenous mepolizumab because this is not currently a licensed delivery route.All of 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 of 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) 1.5 or more). Non-eosinophilic participants treated with benralizumab also showed a significant reduction in exacerbation rates, but no data were available for non-eosinophilic participants, and mepolizumab or reslizumab.We saw modest improvements in validated HRQoL scores with all anti-IL-5 agents in severe eosinophilic asthma. However these did not exceed the minimum clinically important difference for ACQ and Asthma Quality of Life Questionnaire (AQLQ), with St. George's Respiratory Questionnaire (SGRQ) only assessed in two studies. The improvement in HRQoL scores in non-eosinophilic participants treated with benralizumab, the only intervention for which data were available in this subset, was not statistically significant, but the test for subgroup difference was negative.All anti-IL-5 treatments produced a small but statistically significant improvement in mean pre-bronchodilator forced expiratory flow in one second (FEV1) of between 0.08 L and 0.11 L.There were no excess serious adverse events with any anti-IL-5 treatment, and indeed a reduction in favour of mepolizumab that could be due to a beneficial effect on asthma-related serious adverse events. 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 (36/1599 benralizumab versus 9/998 placebo).Mepolizumab, reslizumab and benralizumab all markedly reduced blood eosinophils, but benralizumab resulted in almost complete depletion, whereas a small number remained with mepolizumab and reslizumab. The implications for efficacy and/or adverse events are unclear.

AUTHORS' CONCLUSIONS

Overall our study supports the use of anti-IL-5 treatments as an adjunct to standard of care in people with severe eosinophilic asthma and poor 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. There were no safety concerns regarding mepolizumab or reslizumab, and no 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), and comparing anti-IL-5 treatments to each other and, in people eligible for both, to anti-immunoglobulin E. For benralizumab, future studies should closely monitor rates of adverse events prompting discontinuation.

Anti-Interleukin 5 (IL-5) and IL-5Ra Biological Drugs: Efficacy, Safety, and Future Perspectives in Severe Eosinophilic Asthma

The definition of asthma has changed considerably in recent years, to the extent that asthma is no longer considered a single disease but a heterogeneous disorder that includes several phenotypes and, possibly, endotypes. A more detailed analysis of the immunological mechanisms underlying the pathogenesis of asthma shows interleukin 5 (IL-5) to be a crucial cytokine in several asthma phenotypes. In fact, IL-5 exerts selective action on eosinophils, which, in turn, sustain airway inflammation and worsen asthma symptoms and control. Clinical trials have shown drugs targeting IL-5 or its receptor alpha subunit (IL-5Ra) to be a promising therapeutic approach to severe asthma, whose characteristics render standard therapy of little use: systemic corticosteroids only partially control the disease and have well-known adverse effects, and omalizumab is used for allergic subtypes. Analysis of the design process of clinical trials reveals the importance of patient selection, taking into account both clinical data (e.g., exacerbations, lung function, and quality of life) and biomarkers (e.g., eosinophils, which are predictive of therapeutic response).

Targeted Therapy for Older Patients with Uncontrolled Severe Asthma: Current and Future Prospects

Severe asthma in the elderly places a high burden on affected individuals and society. Emerging therapies target specific phenotypes of the asthma disease spectrum, and can be beneficial for older asthmatics, albeit their response might be altered due to age-related characteristics. Paradoxically, these characteristics are often ground for exclusion from clinical trials. The question thus arises how the senior asthmatic population can successfully enter the era of targeted therapy. Therefore, we highlight characteristics of this population relevant to effective treatment, and review the evidence for targeted therapy in elderly patients. For targeted therapy it is important to account for aging, as this affects the distribution of phenotypes (e.g. late-onset asthma, non-eosinophilic asthma) and may alter biomarkers and drug metabolism. Elderly asthmatics suffer from age-related comorbidities and subsequent polypharmacy. A systematic search into targeted asthma therapy yielded no randomized clinical trials dedicated to older asthmatics. Post hoc analyses of the anti-immunoglobulin E agent omalizumab indicate similar efficacy in both younger and older adults. Conference abstracts on anti-interleukin-5 and anti-interleukin-13 therapy suggest even more pronounced effects of targeted treatments in late-onset disease and in asthmatic patients 65 years or older, but full reports are lacking. For non-eosinophilic asthma in the elderly, there is not yet high-level evidence for targeted therapy, but macrolides may offer a viable option. In conclusion, there is a gap in knowledge regarding the effect of older age on the safety and efficacy of targeted asthma therapy. Further investigations in the elderly are needed, with special emphasis on both late-onset asthma and therapeutics for non-eosinophilic asthma.

Efficacy and Safety of Anti-Interleukin-5 Therapy in Patients with Asthma: A Systematic Review and Meta-Analysis

BACKGROUND

Recent trials have assessed the efficacy and safety of novel monoclonal antibodies such as reslizumab and benralizumab. However, the overall efficacy and safety anti-interleukin (IL) 5 treatment in asthma have not been thoroughly assessed.

METHODS

Randomized controlled trials (RCTs) of anti-IL-5 treatment on patients with asthma published up to October 2016 in PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) that reported pulmonary function, quality of life scores, asthmatic exacerbation rate, blood and sputum eosinophil counts, short-acting β-agonist (SABA) rescue use, and adverse events were included. The pooled mean difference, and relative risks (RR), and 95% confidence intervals (CIs) were calculated using random-effects models.

RESULTS

Twenty studies involving 7100 patients were identified. Pooled analysis revealed significant improvements in FEV1 (first second forced expiratory volume) (MD = 0.09, 95% CI: 0.06-0.12, I2 = 10%), FEV1% (MD = 3.75, 95% CI: 1.66-5.83, I2 = 19%), Asthma Quality of Life Questionnaire (AQLQ) score (MD = 0.22, 95% CI: 0.15-0.30, I2 = 0%), decreased blood, sputum eosinophils and asthmatic exacerbation (RR = 0.66, 95% CI: 0.59-0.73, I2 = 51%); peak expiratory flow (PEF) (MD = 5.45, 95% CI: -2.83-13.72, I2 = 0%), histamine PC20 (MD = -0.62, 95% CI: -1.92-0.68, I2 = 0%) or SABA rescue use (MD = -0.11, 95% CI: -0.3-0.07, I2 = 30%) were unaffected; adverse events were not increased (RR = 0.93, 95% CI: 0.89-0.98, I2 = 46%). No publication bias was observed (Egger's P = 0.78).

CONCLUSIONS

Anti-interleukin 5 monoclonal therapies for asthma could be safe for slightly improving FEV1 (or FEV1% of predicted value), quality of life, and reducing exacerbations risk and blood and sputum eosinophils, but have no significant effect on PEF, histamine PC20, and SABA rescue use. Further trials required to establish to clarify the optimal antibody for different patients.

Monoclonal antibody therapy for the treatment of asthma and chronic obstructive pulmonary disease with eosinophilic inflammation

Eosinophils have been linked with asthma for more than a century, but their role has been unclear. This review discusses the roles of eosinophils in asthma and chronic obstructive pulmonary disease (COPD) and describes therapeutic antibodies that affect eosinophilia. The aims of pharmacologic treatments for pulmonary conditions are to reduce symptoms, slow decline or improve lung function, and reduce the frequency and severity of exacerbations. Inhaled corticosteroids (ICS) are important in managing symptoms and exacerbations in asthma and COPD. However, control with these agents is often suboptimal, especially for patients with severe disease. Recently, new biologics that target eosinophilic inflammation, used as adjunctive therapy to corticosteroids, have proven beneficial and support a pivotal role for eosinophils in the pathology of asthma. Nucala® (mepolizumab; anti-interleukin [IL]-5) and Cinquair® (reslizumab; anti-IL-5), the second and third biologics approved, respectively, for the treatment of asthma, exemplifies these new treatment options. Emerging evidence suggests that eosinophils may contribute to exacerbations and possibly to lung function decline for a subset of patients with COPD. Here we describe the pharmacology of therapeutic antibodies inhibiting IL-5 or targeting the IL-5 receptor, as well as other cytokines contributing to eosinophilic inflammation. We discuss their roles as adjuncts to conventional therapeutic approaches, especially ICS therapy, when disease is suboptimally controlled. These agents have achieved a place in the therapeutic armamentarium for asthma and COPD and will deepen our understanding of the pathogenic role of eosinophils.

Mepolizumab for severe refractory eosinophilic asthma: evidence to date and clinical potential

Severe asthma is characterized by major impairment of quality of life, poor symptom control and frequent exacerbations. Inflammatory, clinical and causative factors identify different phenotypes and endotypes of asthma. In the last few years, new treatment options have allowed for targeted treatments according to the different phenotypes of the disease. To accurately select a specific treatment for each asthmatic variant, the identification of appropriate biomarkers is required. Eosinophilic asthma is a distinct phenotype characterized by thickening of the basement membrane and corticosteroid responsiveness. This review reports the latest evidence on an anti-IL-5 monoclonal antibody, mepolizumab, a new and promising biological agent recently approved by the FDA specifically for the treatment of severe eosinophilic refractory asthma.

Bronchoprotection and bronchorelaxation in asthma: New targets, and new ways to target the old ones

Despite over 50years of inhaled beta-agonists and corticosteroids as the default management or rescue drugs for asthma, recent research suggests that new therapeutic options are likely to emerge. This belief stems from both an improved understanding of what causes and regulates airway smooth muscle (ASM) contraction, and the identification of new targets whose inhibition or activation can relax ASM. In this review we discuss the recent findings that provide new insight into ASM contractile regulation, a revolution in pharmacology that identifies new ways to "tune" G protein-coupled receptors to improve therapeutic efficacy, and the discovery of several novel targets/approaches capable of effecting bronchoprotection or bronchodilation.

Clinical usefulness of mepolizumab in severe eosinophilic asthma

Asthma is a chronic inflammatory disorder of the airways with variable clinical severity from very mild and occasional symptoms to recurrent critical exacerbations, at risk of fatal or near-fatal outcome, in a small percentage of patients. Within the different inflammatory cascades involved in asthma, eosinophils play a central role in the pathogenesis and largely influence disease severity. Interleukin-5 (IL-5) is the main cytokine controlling eosinophil activity and proliferation at the site of inflammation. Mepolizumab was the first biological humanized anti-IL-5 monoclonal antibody tested in randomized clinical trials on eosinophilic asthma and other eosinophilic diseases. On the basis of several positive clinical efficacy data, it has recently been approved by the US Food and Drug Administration for the treatment of severe eosinophilic asthma. Unfortunately, high costs are at present a critical issue. Future studies will probably help in the correct selection of a potential “responder phenotype”, allowing the prescription of this promising therapy to appropriate patients and best define cost-effectiveness issues.

Findings from a pilot Randomised trial of an Asthma Internet Self-management Intervention (RAISIN)

OBJECTIVE

To evaluate the feasibility of a phase 3 randomised controlled trial (RCT) of a website (Living Well with Asthma) to support self-management.

DESIGN AND SETTING

Phase 2, parallel group, RCT, participants recruited from 20 general practices across Glasgow, UK. Randomisation through automated voice response, after baseline data collection, to website access for minimum 12 weeks or usual care.

PARTICIPANTS

Adults (age≥16 years) with physician diagnosed, symptomatic asthma (Asthma Control Questionnaire (ACQ) score ≥1). People with unstable asthma or other lung disease were excluded.

INTERVENTION

'Living Well with Asthma' is a desktop/laptop compatible interactive website designed with input from asthma/ behaviour change specialists, and adults with asthma. It aims to support optimal medication management, promote use of action plans, encourage attendance at asthma reviews and increase physical activity.

OUTCOME MEASURES

Primary outcomes were recruitment/retention, website use, ACQ and mini-Asthma Quality of Life Questionnaire (AQLQ). Secondary outcomes included patient activation, prescribing, adherence, spirometry, lung inflammation and health service contacts after 12 weeks. Blinding postrandomisation was not possible.

RESULTS

Recruitment target met. 51 participants randomised (25 intervention group). Age range 16-78 years; 75% female; 28% from most deprived quintile. 45/51 (88%; 20 intervention group) followed up. 19 (76% of the intervention group) used the website, for a mean of 18 min (range 0-49). 17 went beyond the 2 'core' modules. Median number of logins was 1 (IQR 1-2, range 0-7). No significant difference in the prespecified primary efficacy measures of ACQ scores (-0.36; 95% CI -0.96 to 0.23; p=0.225), and mini-AQLQ scores (0.38; -0.13 to 0.89; p=0.136). No adverse events.

CONCLUSIONS

Recruitment and retention confirmed feasibility; trends to improved outcomes suggest use of Living Well with Asthma may improve self-management in adults with asthma and merits further development followed by investigation in a phase 3 trial.

TRIAL REGISTRATION NUMBER

ISRCTN78556552; Results.