Leukotriene-receptor antagonists versus placebo in the treatment of asthma in adults and adolescents: a systematic review and meta-analysis

Expert opinion on gray areas in asthma management: A lesson from the innovative project "revolution in asthma" of the Italian thoracic society (AIPO-ITS)

BACKGROUND

Despite the availability of numerous guidelines for asthma management, their recommendations are not consistently implemented in clinical practice. This discrepancy between guidelines and real-world practice among Italian healthcare professionals was explored during the "Revolution in Asthma" training program, which identified "gray areas" and barriers preventing clinicians from adopting guideline-based approaches.

OBJECTIVE

This study aims to analyze the key challenges in asthma management and provide evidence-based solutions to improve adherence to guidelines in clinical practice.

METHODS

A group of experts from the Scientific Committee of the Revolution in Asthma project reviewed the program's findings, focusing on three main areas of asthma management: diagnosis, control, and treatment. The experts summarized clinicians' main needs and questions for each area and provided evidence-based responses and practical recommendations.

RESULTS

The study highlights critical challenges in asthma treatment, addressing two key questions: (a) What are the possible uses and indications for short-acting β-agonists in asthma patients? (b) How should asthma treatment be initiated and adjusted based on asthma control? The expert panel developed practical, operational tools to support general practitioners and specialists (pulmonologists and allergists) in optimizing asthma management.

CONCLUSION

This paper serves as a knowledge co-creation initiative, bridging the gap between clinical guidelines and daily practice. By offering concrete recommendations, it aims to enhance the application of guideline-based asthma management among healthcare professionals.

Regular versus as-needed treatments for mild asthma in children, adolescents, and adults: a systematic review and network meta-analysis

BACKGROUND

Inhaled corticosteroids (ICS) are recommended treatment for mild asthma. We aimed to update the evidence on the efficacy and safety of ICS-containing regimens, leukotriene receptor antagonists (LTRA), and tiotropium relative to as-needed (AN) short-acting β2-agonists (SABA) in children (aged 6-11 years) and adolescents/adults.

METHODS

A systematic review of randomized controlled trials (RCTs) of regular and AN treatment for mild asthma was conducted (CRD42022352384). PubMed, Scopus, and ClinicalTrials.gov were searched up to 31st March 2024. RCTs in children or adolescents/adults with mild asthma were eligible if they compared any of the following treatments: ICS alone or in combination with fast-acting bronchodilators (FABA, i.e., formoterol or SABA) or long-acting β2-agonists (LABA), LTRA, tiotropium, and SABA alone, for the following outcomes: exacerbations, asthma symptoms, forced expiratory volume in 1 s (FEV1), asthma-specific quality-of-life (QoL), or severe adverse events (SAEs). The two-stage network meta-analysis (NMA) was used to pool risk ratios (RR) or mean differences for treatment outcomes. The risk of bias was assessed using the Revised Cochrane risk-of-bias tool for randomized trials (RoB2). This review followed the PRISMA reporting guideline and the PRISMA checklist is presented in Additional file 2.

RESULTS

Thirteen RCTs in children and 29 in adolescents/adults were included. Regular ICS ranked best for preventing exacerbations and improving FEV1 in children. NMA of RCTs suggested regular ICS were better in preventing exacerbations than LTRA (RR [95% confidence intervals], (0.81 [0.69,0.96]) and AN-SABA (0.61 [0.48,0.78]), and not different from AN-ICS (0.83 [0.62,1.12]). In adolescents/adults, for preventing severe exacerbations, regular ICS outperformed AN-SABA (0.58 [0.46,0.73]), but AN-ICS/FABA (0.73 [0.54,0.97]), and regular ICS/LABA (0.68 [0.48,0.97]) surpassed regular ICS. Symptom relief and improved FEV1 were not different among the ICS-containing regimens. Regular ICS ranked best for improved QoL and least likely for SAEs.

CONCLUSIONS

Regular ICS use may be the most effective treatment for preventing exacerbation and increasing FEV1 in children with mild asthma. In adolescents/adults, ICS-containing regimens outperformed AN-SABA for exacerbation prevention. With varying degrees of heterogeneity, severe exacerbation risk in adolescents/adults might be lower with regular ICS/LABA or AN-ICS/FABA than regular ICS, where AN-ICS/FABA may not be suitable for patients with low FEV1. Additionally, regular ICS use may enhance FEV1 and QoL more than AN-SABA and LTRA.

Trends in prescribing montelukast in patients with asthma in real-life: Results from the Turkish adult asthma registry

Montelukast, a leukotriene receptor antagonist (LTRA) approved for the treatment of asthma and allergic rhinitis, is widely used, though real-world data on its application in asthma management remain limited. This registry-based study evaluated the use of montelukast in adult asthma patients, examining demographic and disease characteristics, asthma control status, asthma phenotypes, presence of atopy, and treatment regimens. Among 2053 patients analyzed, 61.76% (n = 1268; mean age: 46.2 ± 14.3 years), predominantly females (~76%), received montelukast. Montelukast users showed higher rates of allergic rhinitis (P < 0.001), hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) (P = 0.008), and chronic rhinosinusitis (P = 0.008). Montelukast group also had higher atopy and total IgE levels and tended to be more eosinophilic. Montelukast was commonly preferred in allergic, eosinophilic, NSAID-exacerbated respiratory disease, and severe asthma phenotypes (P < 0.001). Patients receiving Steps 4 and 5 treatments are more likely to be prescribed montelukast (P < 0.001). Montelukast usage was higher among patients with uncontrolled asthma [ACT< 20 (OR:1.29, 95%CI:1.052-1.582, P = 0.014)]. In addition, logistic regression analyses identified the main factors associated with increased montelukast use as; female gender (OR:1.33, 95%CI:1.041-1.713, P = 0.02), presence of atopy (OR:1.46, 95%CI:1.157-1.864, P = 0.002), comorbid allergic rhinitis (OR:2.12, 95%CI:1.679-2.293, P < 0.001), and severe asthma (OR:2.18, 95%CI:1.712-2.784, P < 0.001). These findings reveal that montelukast use is prevalent among asthma patients, particularly in females, middle-aged adults, and those with comorbid allergic rhinitis, uncontrolled asthma, or specific asthma phenotypes, underscoring the factors that influence its prescription in asthma management.

Montelukast in paediatric asthma and allergic rhinitis: a systematic review and meta-analysis

BACKGROUND

We aim to assess the impact of montelukast on paediatric patients with asthma/allergic rhinitis, measured using patient-reported outcome measures, compared with other treatments or placebo.

METHODS

Protocol registration CRD42020216098 (www.crd.york.ac.uk/PROSPERO). MEDLINE and Embase databases were used to conduct the search. Two authors independently selected studies and extracted data, and a third reviewer resolved discrepancies. Meta-analyses were constructed to estimate the standardised mean difference (SMD) using a random-effects model.

RESULTS

Out of 3937 articles identified, 49 studies met the inclusion criteria, mostly randomised clinical trials (sample sizes: 21-689 patients). The SMD of change pooled estimators for the global, mental and physical domains of health-related quality of life were not statistically significant. For daytime and night-time symptoms scores, the SMD (95% CI) was in favour of inhaled corticosteroids (-0.12, -0.20- -0.05 and -0.23, -0.41- -0.06, respectively). The pooled estimator for global asthma symptoms was better for montelukast when compared with placebo (0.90, 0.44-1.36).

CONCLUSIONS

The synthesis of the available evidence suggests that, in children and adolescents, montelukast was effective in controlling asthma symptoms when compared with placebo, but inhaled corticosteroids were superior in controlling symptoms, especially at night-time. These findings of our systematic review concur with current guidelines for asthma treatment.

Stepwise Approach in Asthma Revisited 2023: Expert Panel Opinion of Turkish Guideline of Asthma Diagnosis and Management Group

Introduction of inhaled corticosteroids (ICS) has been the cornerstone of the long-term management of asthma. ICSs either alone or in combination with long-acting beta-2 agonists have been shown to be associated with favorable asthma outcomes. However, asthma control is still reported to be below expectations all around the world. Research in the last decades focusing on the use of ICS/formoterol both as maintenance and as needed (maintenance and reliever therapy approach) showed improved asthma outcomes. As a result of recent developments, Turkish Asthma Guidelines group aimed to revise asthma treatment recommendations. In general, we recommend physicians to consider the risk factors for poor asthma outcomes, patients' compliance and expectations and then to determine "a personalized treatment plan." Importantly, the use of short-acting beta-2 agonists alone as a symptom reliever in asthma patients not using regular ICS is no longer recommended. In stepwise treatment approach, we primarily recommend to use ICS-based controllers and initiate ICS as soon as possible. We define 2 different treatment tracks in stepwise approaches as maintenance and reliever therapy or fixed-dose therapy and equally recommend each track depending on the patient's risks as well as decision of physicians in a personalized manner. For both tracks, a strong recommendation was made in favor of using add-on treatments before initiating phenotype-specific treatment in step 5. A strong recommendation was also made in favor of using biologic agents and/or aspirin treatment after desensitization in severe asthma when indicated.

Mild asthma: Lessons learned and remaining questions

Patients living with mild disease represent the largest proportion of asthma patients. There are significant challenges in proposing a definition that would best describe these patients, while also accurately identifying at-risk individuals. Current literature suggests considerable inflammatory and clinical heterogeneity within this group. Research has shown that these patients are at risk of poor control, exacerbations, lung function decline, and death. Despite conflicting data on its prevalence, eosinophilic inflammation appears to be a predictor of poorer outcomes in mild asthma. There is an immediate need to better understand phenotypic clusters in mild asthma. It is also important to understand factors that influence disease progression and remission, as it is evident that both vary in mild asthma. Guided by robust literature that supports inhaled corticosteroid-based strategies over short-acting beta-agonist (SABA) reliant regimens, the management of these patients has evolved considerably. Unfortunately, SABA use remains high in clinical practice despite strong advocacy from the Global Initiative for Asthma. Future mild asthma research should explore the role of biomarkers, develop prediction tools based on composite risk scores, and explore targeted therapies at least for at-risk individuals.

Questions in Mild Asthma: An Official American Thoracic Society Research Statement

Background: Patients with mild asthma are believed to represent the majority of patients with asthma. Disease-associated risks such as exacerbations, lung function decline, and death have been understudied in this patient population. There have been no prior efforts from major societies to describe research needs in mild asthma. Methods: A multidisciplinary, diverse group of 24 international experts reviewed the literature, identified knowledge gaps, and provided research recommendations relating to mild asthma definition, pathophysiology, and management across all age groups. Research needs were also investigated from a patient perspective, generated in conjunction with patients with asthma, caregivers, and stakeholders. Of note, this project is not a systematic review of the evidence and is not a clinical practice guideline. Results: There are multiple unmet needs in research on mild asthma driven by large knowledge gaps in all areas. Specifically, there is an immediate need for a robust mild asthma definition and an improved understanding of its pathophysiology and management strategies across all age groups. Future research must factor in patient perspectives. Conclusions: Despite significant advances in severe asthma, there remain innumerable research areas requiring urgent attention in mild asthma. An important first step is to determine a better definition that will accurately reflect the heterogeneity and risks noted in this group. This research statement highlights the topics of research that are of the highest priority. Furthermore, it firmly advocates the need for engagement with patient groups and for more support for research in this field.

The relationship between obstructive sleep apnea and asthma severity and vice versa: a systematic review and meta-analysis

BACKGROUND

There is a great association between the prevalence of obstructive sleep apnea (OSA) and asthma. Nonetheless, whether OSA impacts lung function, symptoms, and control in asthma and whether asthma increases the respiratory events in OSA are unknown. This meta-analysis aimed to examine the relationship between obstructive sleep apnea and asthma severity and vice versa.

METHODS

We carried out a systematic search of PubMed, EMBASE, and Scopus from inception to September 2022. Primary outcomes were lung function, parameters of polysomnography, the risk of OSA in more severe or difficult-to-control asthmatic patients, and the risk of asthma in patients with more severe OSA. Heterogeneity was examined with the Q test and I² statistics. We also performed subgroup analysis, Meta-regression, and Egger's test for bias analysis.

RESULTS

34 studies with 27,912 subjects were totally included. The results showed that the comorbidity of OSA aggravated lung function in asthmatic patients with a consequent decreased forced expiratory volume in one second %predicted (%FEV1) and the effect was particularly evident in children. %FEV1 tended to decrease in adult asthma patients complicated with OSA, but did not reach statistical significance. Interestingly, the risk of asthma seemed to be slightly lower in patients with more severe OSA (OR = 0.87, 95%CI 0.763-0.998). Asthma had no significant effect on polysomnography, but increased daytime sleepiness assessed by the Epworth Sleepiness Scale in OSA patients (WMD = 0.60, 95%CI 0.16-1.04). More severe asthma or difficult-to-control asthma was independently associated with OSA (odds ratio (OR) = 4.36, 95%CI 2.49-7.64).

CONCLUSION

OSA was associated with more severe or difficult-to-control asthma with decreased %FEV₁ in children. The effect of OSA on lung function in adult patients should be further confirmed. Asthma increased daytime sleepiness in OSA patients. More studies are warranted to investigate the effect of asthma on OSA severity and the impact of different OSA severity on the prevalence of asthma. It is strongly recommended that people with moderate-to-severe or difficult-to-control asthma screen for OSA and get the appropriate treatment.

Prescription rate and treatment patterns for allergic rhinitis from 2010 to 2018 in South Korea: a retrospective study

BACKGROUND

There has been little investigation on how guidelines for allergic rhinitis (AR) treatment are applied in current clinical practice. We aimed to analyze prescription trends and patterns for AR treatment according to patient characteristics over a 9-year period in Korea.

METHODS

We used cross-sectional data from the Korean Health Insurance Review & Assessment Service National Patient Sample from 2010 to 2018. We analyzed 1,719,194 patients with AR as the principal diagnosis. Prescription rates of antihistamines, steroids, and other drugs; combination prescriptions; and first-choice prescriptions were analyzed.

RESULTS

The prescription rate of first-generation antihistamines decreased over the years (2010: 29.13; 2018: 23.41). By contrast, the prescription rate of systemic steroids (2010: 23.60; 2018: 28.70), nasal steroids (2010: 9.70; 2018: 14.67), and leukotriene receptor antagonists (LTRAs) (2010: 11.13; 2018: 26.56) increased. The prescription rate of steroids was lower in patients aged 0-5 years and ≥ 65 years than in other age groups and that of LTRAs was the highest in patients aged 0-5 years. The rate of combination prescribing antihistamines and nasal steroids increased (2010: 7.99; 2018: 12.09). The rate of first-choice prescriptions with antihistamines and nasal steroids also increased (2010: 4.72; 2018: 7.24).

CONCLUSIONS

The results confirmed a decrease in antihistamine prescriptions, especially with first-generation, and an increase in steroid and LTRA prescriptions in patients with AR in Korea. Regarding prescription patterns, steroids were increasingly prescribed in combination with antihistamines. However, the trend was opposite in the 0-5 years and ≥ 65 years groups.

Recent Insights into the Management of Inflammation in Asthma

The present prevailing inflammatory paradigm in asthma is of T2-high inflammation orchestrated by key inflammatory cells like Type 2 helper lymphocytes, innate lymphoid cells group 2 and associated cytokines. Eosinophils are key components of this T2 inflammatory pathway and have become key therapeutic targets. Real-world evidence on the predominant T2-high nature of severe asthma is emerging. Various inflammatory biomarkers have been adopted in clinical practice to aid asthma characterization including airway measures such as bronchoscopic biopsy and lavage, induced sputum analysis, and fractional exhaled nitric oxide. Blood measures like eosinophil counts have also gained widespread usage and multicomponent algorithms combining different parameters are now appearing. There is also growing interest in potential future biomarkers including exhaled volatile organic compounds, micro RNAs and urinary biomarkers. Additionally, there is a growing realisation that asthma is a heterogeneous state with numerous phenotypes and associated treatable traits. These may show particular inflammatory patterns and merit-specific management approaches that could improve asthma patient outcomes. Inhaled corticosteroids (ICS) remain the mainstay of asthma management but their use earlier in the course of disease is being advocated. Recent evidence suggests potential roles for ICS in combination with long-acting beta-agonists (LABA) for as needed use in mild asthma whilst maintenance and reliever therapy regimes have gained widespread acceptance. Other anti-inflammatory strategies including ultra-fine particle ICS, leukotriene receptor antagonists and macrolide antibiotics may show efficacy in particular phenotypes too. Monoclonal antibody biologic therapies have recently entered clinical practice with significant impacts on asthma outcomes. Understanding of the efficacy and use of those agents is becoming clearer with a growing body of real-world evidence as is their potential applicability to other treatable comorbid traits. In conclusion, the evolving understanding of T2 driven inflammation alongside a treatable traits disease model is enhancing therapeutic approaches to address inflammation in asthma.

The roles of lipid mediators in type I hypersensitivity

Type I hypersensitivity is an immediate immune reaction that involves IgE-mediated activation of mast cells. Activated mast cells release chemical mediators, such as histamine and lipid mediators, which cause allergic reactions. Recent developments in detection devices have revealed that mast cells simultaneously release a wide variety of lipid mediators. Mounting evidence has revealed that mast cell-derived mediators exert both pro- and anti-inflammatory functions and positively and negatively regulate the development of allergic inflammation. This review presents the roles of major lipid mediators released from mast cells. Author believes this review will be helpful for a better understanding of the pathogenesis of allergic diseases and provide a new strategy for the diagnosis and treatment of allergic reactions.

A Current Perspective of Allergic Asthma: From Mechanisms to Management

Asthma is a result of heterogenous, complex gene-environment interactions with variable clinical phenotypes, inflammation, and remodeling. It affects more than 330 million of people worldwide throughout their educational and working lives, while exacerbations put a heavy cost/burden on productivity. Childhood asthma is characterized by a predominance of allergic sensitization and multimorbidity, while in adults polysensitization has been positively associated with asthma occurrence. Despite significant improvements in recent decades, asthma management remains challenging. Recently, a group of specialists suggested that the term "asthma" should be preferably used as a descriptive term for symptoms. Moreover, type 2 inflammation has emerged as a pivotal disease mechanism including overlapping endotypes of specific IgE production, while type 2-low asthma includes several disease endotypes. Optimal asthma control requires both appropriate pharmacological interventions, tailored to each patient, as well as trigger avoidance measures. Regular monitoring for maintenance of symptom control, preservation of lung function, and detection of treatment-related adverse effects are warranted. Allergen-specific immunotherapy and the advent of new targeted therapies for patients with difficult to control asthma offer diverse treatment options. The current review summarizes up-to-date knowledge on epidemiology, definitions, diagnosis, and current therapeutic strategies.

Current perspective on eicosanoids in asthma and allergic diseases: EAACI Task Force consensus report, part I

Eicosanoids are biologically active lipid mediators, comprising prostaglandins, leukotrienes, thromboxanes, and lipoxins, involved in several pathophysiological processes relevant to asthma, allergies, and allied diseases. Prostaglandins and leukotrienes are the most studied eicosanoids and established inducers of airway pathophysiology including bronchoconstriction and airway inflammation. Drugs inhibiting the synthesis of lipid mediators or their effects, such as leukotriene synthesis inhibitors, leukotriene receptors antagonists, and more recently prostaglandin D₂ receptor antagonists, have been shown to modulate features of asthma and allergic diseases. This review, produced by an European Academy of Allergy and Clinical Immunology (EAACI) task force, highlights our current understanding of eicosanoid biology and its role in mediating human pathology, with a focus on new findings relevant for clinical practice, development of novel therapeutics, and future research opportunities.

Structure-Based Virtual Screening of Ultra-Large Library Yields Potent Antagonists for a Lipid GPCR

Cysteinyl leukotriene G protein-coupled receptors, CysLT1R and CysLT2R, regulate bronchoconstrictive and pro-inflammatory effects and play a key role in allergic disorders, cardiovascular diseases, and cancer. CysLT1R antagonists have been widely used to treat asthma disorders, while CysLT2R is a potential target against uveal melanoma. However, very few selective antagonist chemotypes for CysLT receptors are available, and the design of such ligands has proved to be challenging. To overcome this obstacle, we took advantage of recently solved crystal structures of CysLT receptors and an ultra-large Enamine REAL library, representing a chemical space of 680 M readily available compounds. Virtual ligand screening employed 4D docking models comprising crystal structures of CysLT1R and CysLT2R and their corresponding ligand-optimized models. Functional assessment of the candidate hits yielded discovery of five novel antagonist chemotypes with sub-micromolar potencies and the best Ki = 220 nM at CysLT1R. One of the hits showed inverse agonism at the L129Q constitutively active mutant of CysLT2R, with potential utility against uveal melanoma.

Role of Montelukast as Monotherapy in Improving Quality of Life of an Asthmatic Patient in Pakistan

Introduction: Uncontrolled and inadequately managed asthma substantially reduces Quality of Life (QOL) and can lead to premature death. The aim of this study is to understand the role of montelukast in improving quality of life in asthmatic patients by comparing it with placebo.

Methods: This prospective, single-arm, interventional study was conducted from September 2019 to February 2020 in the pulmonology outpatient department of a tertiary care hospital in Pakistan. All patients were prescribed montelukast (10 mg once daily).

Results: At day 28, participants had a higher score on the Asthma Quality of Life Questionnaire-Standard (AQLQ-S) overall and in all sub-domains compared to day 0. The improvement was significant overall and for the sub-domains of symptoms, activity limitations, and environmental stimuli.

Conclusion: Montelukast has an effective role in asthma control as well as in improving the quality of life in the Pakistani population.

Targeting lipid mediators in asthma: time for reappraisal

PURPOSE OF REVIEW

In the past decades, cysteinyl leukotrienes (CysLTs) and prostaglandin D2 have been recognized as key mediators of asthma and comorbid conditions for their potent broncho-active and proinflammatory properties. However, both the development and initial positioning of small molecules targeting these lipid mediators [i.e., leukotriene-synthesis inhibitors, CysLT-antagonists, and chemoattractant receptor homologous molecule on T-helper2-cells (CRTH2) antagonists] experienced drawbacks by lacking adequate biomarkers to define potential responders.

RECENT FINDINGS

New insights into the mechanisms of airway inflammation in asthma including the interaction of leukotrienes and prostanoids has uncovered potential therapeutic targets. Emerging application of biomarkers in more recent clinical studies helped identify responders to therapies targeting lipid mediators and demonstrated their clinical efficacy in distinct asthma phenotypes and endotypes.

SUMMARY

Interest in small molecules targeting lipid mediators in asthma and related conditions is emerging. Several clinical trials evaluating the efficacy and safety of CRTH2 (Prostaglandin D2 receptor 2) antagonists are ongoing. There is an urgent need for sensitive biomarkers to identify responders to such therapies and for monitoring of (long-term) effects. Furthermore, evaluation of effectiveness of combining different agents targeting lipid mediators or combining them with available or emerging biologics may uncover other potential benefits in certain asthma populations warranting future research.

Structural basis of ligand selectivity and disease mutations in cysteinyl leukotriene receptors

Cysteinyl leukotriene G protein-coupled receptors CysLT₁ and CysLT₂ regulate pro-inflammatory responses associated with allergic disorders. While selective inhibition of CysLT₁R has been used for treating asthma and associated diseases for over two decades, CysLT₂R has recently started to emerge as a potential drug target against atopic asthma, brain injury and central nervous system disorders, as well as several types of cancer. Here, we describe four crystal structures of CysLT₂R in complex with three dual CysLT₁R/CysLT₂R antagonists. The reported structures together with the results of comprehensive mutagenesis and computer modeling studies shed light on molecular determinants of CysLTR ligand selectivity and specific effects of disease-related single nucleotide variants.

Cysteinyl leukotriene G protein-coupled receptors CysLT₁ and CysLT₂ regulate pro-inflammatory responses associated with allergic disorders. Here, authors describe four crystal structures of CysLT₂R in complex with three dual CysLT₁R/CysLT₂R antagonists, which shed light on CysLTR ligand selectivity.

Current state and future prospect of the therapeutic strategy targeting cysteinyl leukotriene metabolism in asthma

Asthma is an allergic disorder with dominant type 2 airway inflammation, and its prevalence is increasing worldwide. Inhalation of corticosteroids is the primary treatment for asthma along with add-on drugs, including long-acting β2 agonists and/or cysteinyl leukotriene (cys-LT) receptor antagonists, in patients with poorly controlled asthma. Cys-LTs are composed of leukotriene C4 (LTC₄), LTD₄, and LTE₄, which are enzymatically metabolized from arachidonic acid. These molecules act as inflammatory mediators through different types of high-affinity receptors, namely, CysLT₁, CysLT₂, and CysLT₃ (also named as GPR99). CysLT₁ antagonists possessing anti-inflammatory and bronchodilatory effects can be orally administered to patients with asthma. Recently, molecular biology-based studies have revealed the mechanism of inflammatory responses via other receptors, such as CysLT₂ and CysLT₃, as well as the importance of upstream inflammatory regulators, including type 2 cytokines (e.g., interleukins 4 and 5), in controlling cys-LT metabolism. These findings indicate the therapeutic potential of pharmacological agents targeting cys-LT metabolism-related receptors and enzymes, and antibody drugs neutralizing or antagonizing type 2 cytokines. This review focuses on the current state and future prospect of the therapeutic strategy targeting cys-LT metabolism.

ERS/EAACI statement on severe exacerbations in asthma in adults: facts, priorities and key research questions

Despite the use of effective medications to control asthma, severe exacerbations in asthma are still a major health risk and require urgent action on the part of the patient and physician to prevent serious outcomes such as hospitalisation or death. Moreover, severe exacerbations are associated with substantial healthcare costs and psychological burden, including anxiety and fear for patients and their families. The European Academy of Allergy and Clinical Immunology (EAACI) and the European Respiratory Society (ERS) set up a task force to search for a clear definition of severe exacerbations, and to also define research questions and priorities. The statement includes comments from patients who were members of the task force.

The Role of Leukotrienes as Potential Therapeutic Targets in Allergic Disorders

Leukotrienes (LTs) are lipid mediators that play pivotal roles in acute and chronic inflammation and allergic diseases. They exert their biological effects by binding to specific G-protein-coupled receptors. Each LT receptor subtype exhibits unique functions and expression patterns. LTs play roles in various allergic diseases, including asthma (neutrophilic asthma and aspirin-sensitive asthma), allergic rhinitis, atopic dermatitis, allergic conjunctivitis, and anaphylaxis. This review summarizes the biology of LTs and their receptors, recent developments in the area of anti-LT strategies (in settings such as ongoing clinical studies), and prospects for future therapeutic applications.

Prevalence of Montelukast Use as an Add-On Therapy among Iraqi Asthmatics on Treatment Attending Al-Kindy Teaching Hospital and Al-Zahraa Center of Asthma and Allergy

BACKGROUND:

Montelukast (Singulair) is a cysteinyl leukotriene receptor antagonist, used for the maintenance treatment of asthma and to relieve symptoms of seasonal allergic rhinitis and asthma, also used for exercise-induced bronchospasm.

AIM:

This study was performed to determine the prevalence of Montelukast use as an add-on therapy among Iraqi asthmatic patients on treatment. Comparing the effectiveness of regimens with and without montelukast.

METHODS:

This descriptive cross-sectional study was carried out on 73 Iraqi asthmatic patients on treatment of both sexes with age range (18-60) years old, attending Al-Kindy Teaching Hospital and Al-Zahraa Centre of Asthma and Allergy, Baghdad, for the period between February and March 2017. A questionnaire was specifically prepared to meet the objectives and was used to collect the data of the study.

RESULTS:

There was a significant statistical reduction of frequency in asthmatic attacks after Montelukast treatment (p-value < 0.05). Out of 73 patients, 39 were males, and 34 were females, 46 were jobless, 37 were married, 63 were urban residents, 63 were educated. Prevalence of exacerbation factors was as following: infection was found in 60.3% of the patients, exercise in 57.5%, dust in 72.6%, smoking in 60.6%, food in 24.7%, others (stress, perfumes) in 20.5%. The prevalence of Montelukast use in this study was 46% (34 patients). Out of 34 patients using Montelukast, 28 were using inhaled salbutamol, 5 were using oral salbutamol, 15 were using inhaled corticosteroids, 9 were using systematic corticosteroids, 2 were using xanthines, and 6 were using ketotifen.

CONCLUSION:

Montelukast was used as add-on therapy with the inhaled corticosteroids to reduce the required dose of inhaled corticosteroids also the use of Montelukast lead to reduced number of exacerbations which will be reflected on the use of inhaled salbutamol and systematic corticosteroids. Also, Montelukast was superior to xanthines and ketotifen as an add-on therapy.

Role of Montelukast in Improving Quality of Life in Patients with Persistent Asthma

Introduction

Maintenance therapy of asthma has a crucial role in keeping the disease dormant and preventing frequent acute exacerbations. Asthma control may be achieved by inhaled corticosteroids (ICS) and/or long-acting beta-agonists (LABA). Leukotriene receptor antagonist - montelukast - may be added as an add-on to ICS/LABA or may also be given in monotherapy. The aim of this study was to evaluate the role of montelukast monotherapy as asthma control and its impact on the quality of life of these patients.

Methods

In this prospective, open-label, interventional study, montelukast 10 mg once daily was given to patients with mild to moderate persistent asthma for four weeks. Quality of life (QOL) was assessed on the Asthma Quality of Life Questionnaire - Standard (AQLQ-S) questionnaire. Asthma control was assessed on the Asthma Control Test (ACT). Data was entered and analyzed using SPSS version 23.0.

Results

On AQLQ-S, overall QOL improved with one month of montelukast therapy significantly. On sub-scales, except for emotional function, all other three sub-scales including symptoms, activity limitation, and environmental function improved significantly. Asthma control score also significantly improved with one month of montelukast therapy.

Conclusion

Montelukast has an effective role in asthma control and improvement of QOL in patients with mild to moderate persistent asthma.

Effectiveness and Quality of Life with Montelukast in Asthma - A double-blind randomized control trial

Objective:

To determine the role of montelukast – a leukotriene receptor antagonist (LTRA) – in improving the quality of life (QOL) and asthma control of adult patients with mild to moderate persistent asthma.

Methods:

Randomized, double-blind, placebo-controlled, non-crossover trial was conducted from March 2017 till November 2018 in three hospitals of Karachi and Hyderabad. Adults of age 15 years or more with mild to moderate persistent asthma. Treatment group was administered tablet montelukast 10mg once daily; the other group was given a similar looking placebo; as an adjuvant to the current medication. QOL was assessed with Asthma Quality of Life Questionnaire – Standard (AQLQ-S) before and after the treatment. Asthma control was monitored via Asthma Control Test (ACT).

Results:

After 4 weeks, the mean ± SD of overall QOL on AQLQ-S improved from 3.74±0.88 to 5.06±0.89 for montelukast group and from 3.58±0.92 to 4.71±0.97 for placebo group (p=0.02). The improvement in sub-domains of symptoms, activity, and emotional functions was not significant; however, the sub-domain “environmental stimuli” significantly improved with 5.06±0.89 for montelukast group and 4.71±0.97 for placebo group (p=0.02). The mean ± SD of ACT, after four weeks, for montelukast group was 18.19±2.91 and for placebo group 17.28±3.36. Only on ACT, Montelukast did not show any statistically insignificant results.

Conclusion:

The role of montelukast in improving QOL of adult patients with mild to moderate persistent asthma is quite beneficial. It improves patient quality of life. It has the ease of once daily oral administration and also eradicates side effects associated with long-term adherence to steroids.

Antileukotrienes improve naso-ocular symptoms and biomarkers in patients with NARES and asthma

OBJECTIVE

The aim of our study was to analyze the montelukast effectiveness in improving oculonasal symptoms, patient-reported outcomes (PROs), and eosinophilic biomarkers in patients with nonallergic rhinitis eosinophilic syndrome (NARES).

METHODS

We enrolled prospectively 80 symptomatic patients treated with 10 mg once a day of montelukast in monotherapy for 2 months. All patients were investigated before and after treatment. Nasal symptoms (nasal obstruction, rhinorrhoea, sneezing, nasal itching), ocular symptoms (redness/puffiness, watery eyes), and other PROs (olfactory dysfunction, difficulty going to sleep, nighttime awakenings, and nasal congestion on awakening) were scored by visual analogic scale. The following clinical scores were assessed: Total Nasal Symptom Score (T4NSS), Total Ocular Symptom Score (T2OSS), Total Symptom Score of Patient-Reported Outcomes (TSS-PROs), and a Composite Symptoms Score (CSS). Patients were classified as responders when a reduction of at least 50% of the CSS was observed. Before and after treatment, the eosinophilic biomarkers in nasal lavage were analyzed: nasal eosinophilia (number of eosinophils per high power field), eotaxin-1 and eotaxin-2.

RESULTS

After treatment, significant reductions were observed for all the symptom scores. Forty-two of 78 patients were considered responders. A significant reduction of eosinophils in nasal mucosa and of levels of eotaxin-1 and eotaxin-2 in nasal lavage were observed after treatment in responder patients. Patients with asthma had an increased probability to be responders.

CONCLUSION

NARES patients may benefit from treatment with montelukast. In particular, the presence of concomitant asthma may be predictive of a greater efficacy.

LEVEL OF EVIDENCE

2 Laryngoscope, 129:551-557, 2019.

Step-up and step-down treatments for optimal asthma control in children and adolescents

OBJECTIVE

To review therapeutic options for stepwise management of pediatric asthma in the context of this population's unique needs such as potential effects of asthma, treatments, or both on growth and psychosocial development, and caregiver involvement.

DATA SOURCES AND STUDY SELECTION

We conducted PubMed searches to identify relevant articles then reviewed resultant articles, guidelines for asthma management in children, and articles from personal files.

RESULTS

Stepwise management of asthma, similar to adults, is recommended for children in current global and US guidelines. Treatment may be stepped up or stepped down temporarily or long-term based on response over time. Inhaled corticosteroids remain the recommended treatment for persistent childhood asthma and any potential small effects on growth are considered relatively minor compared with their benefit. Controller medication options for patients <18 years old are limited, especially for Global Initiative for Asthma Steps 2-5. The long-acting antimuscarinic antagonist tiotropium (Steps 4/5, patients aged ≥12 years) and in certain circumstances (Step 5), anti-immunoglobulin E (aged ≥6 years) and interleukin-5 antibodies (aged ≥12 years) are newer treatment options. Tiotropium is indicated in the United States and Europe for patients ≥6 years old. Stepping down treatment, which is recommended but infrequently practiced, can maintain symptom control and minimize adverse events while substantially reducing costs. Patient education and better monitoring remain important for self-management and optimum outcomes.

CONCLUSION

A need exists to target individual treatment goals for children with asthma by using step-up and step-down approaches to maximize treatment benefits and minimize potential adverse effects.

Asthma Phenotypes and Endotypes: Implications for Personalised Therapy

Asthma is increasingly recognised as a heterogeneous group of diseases with similar clinical presentations rather than a singular disease entity. Asthma was historically categorised by clinical symptoms; however, newer methods of subgrouping, describing and categorising the disease have sub-defined asthma. These sub-definitions are intermittently called phenotypes or endotypes, but the real meanings of these words are poorly understood. Novel treatments are currently and increasingly available, partly in the monoclonal antibody environment, and also some physical therapies (bronchial thermoplasty), but additionally small molecules are not far away from clinical practice. Understanding the disease pathogenesis and the mechanism of action more completely may enable identification of treatable traits, biomarkers, mediators and modifiable therapeutic targets. However, there remains a danger that clinicians become preoccupied with the concept of endotypes and biomarkers, ignoring therapies that are hugely effective but have no companion biomarker. This review discusses our understanding of the concept of phenotypes and endotypes in appreciating and managing the heterogeneous condition that is asthma. We consider the role of functional imaging, physiology, blood-, sputum- and breath-based biomarkers and clinical manifestations that could be used to produce a personalised asthma profile, with implications on prognosis, pathophysiology and most importantly specific therapeutic responses. With the advent of increasing numbers of biological therapies and other interventional options such as bronchial thermoplasty, the importance of targeting expensive therapies to patients with the best chance of clinical response has huge health economic importance.

The pediatric asthma yardstick: Practical recommendations for a sustained step-up in asthma therapy for children with inadequately controlled asthma

Current asthma guidelines recommend a control-based approach to management involving assessment of impairment and risk followed by implementation of treatment strategies individualized according to the patient's needs and preferences. However, for children with asthma, achieving control can be elusive. Although tools are available to help children (and families) track and manage day-to-day symptoms, when and how to implement a longer-term step-up in care is less clear. Furthermore, treatment is challenged by the 3 age groups of childhood-adolescence (12-18 years old), school age (6-11 years old), and young children (≤5 years old)-and what works for 1 age group might not be the best approach for another. The Pediatric Asthma Yardstick provides an in-depth assessment of when and how to step-up therapy for the child with not well or poorly controlled asthma. Development of this tool follows others in the Yardstick series, presenting patient profiles and step-up strategies based on current guidance documents, but modified according to newer data and the authors' combined clinical experience. The objective is to provide clinicians who treat children with asthma practical and clinically relevant recommendations for each step-up and each intervention, with the intent of helping practitioners better treat their pediatric patients with asthma, particularly those who do not always respond to recommended therapies.

Lipid Mediators of Allergic Disease: Pathways, Treatments, and Emerging Therapeutic Targets

Bioactive lipids are critical regulators of inflammation. Over the last 75 years, these diverse compounds have emerged as clinically-relevant mediators of allergic disease pathophysiology. Animal and human studies have demonstrated the importance of lipid mediators in the development of asthma, allergic rhinitis, urticaria, anaphylaxis, atopic dermatitis, and food allergy. Lipids are critical participants in cell signaling events which influence key physiologic (bronchoconstriction) and immune phenomena (degranulation, chemotaxis, sensitization). Lipid-mediated cellular mechanisms including: (1) formation of structural support platforms (lipid rafts) for receptor signaling complexes, (2) activation of a diverse family of G-protein coupled receptors, and (3) mediating intracellular signaling cascades by acting as second messengers. Here, we review four classes of bioactive lipids (platelet activating factor, the leukotrienes, the prostanoids, and the sphingolipids) with special emphasis on lipid synthesis pathways and signaling, atopic disease pathology, and the ongoing development of atopy treatments targeting lipid mediator pathways.

The leukotriene receptor antagonist montelukast and its possible role in the cardiovascular field

BACKGROUND

Cysteinyl leukotrienes (LTC4, LTD4, and LTE4) are pro-inflammatory mediators of the 5-lipooxygenase (5-LO) pathway, that play an important role in bronchoconstriction, but can also enhance endothelial cell permeability and myocardial contractility, and are involved in many other inflammatory conditions. In the late 1990s, leukotriene receptor antagonists (LTRAs) were introduced in therapy for asthma and later on, approved for the relief of the symptoms of allergic rhinitis, chronic obstructive pulmonary disease, and urticaria. In addition, it has been shown that LTRAs may have a potential role in preventing atherosclerosis progression.

PURPOSE

The aims of this short review are to delineate the potential cardiovascular protective role of a LTRA, montelukast, beyond its traditional use, and to foster the design of appropriate clinical trials to test this hypothesis.

RESULTS AND CONCLUSIONS

What it is known about leukotriene receptor antagonists? •Leukotriene receptor antagonist, such as montelukast and zafirlukast, is used in asthma, COPD, and allergic rhinitis. • Montelukast is the most prescribed CysLT₁ antagonist used in asthmatic patients. • Different in vivo animal studies have shown that leukotriene receptor antagonists can prevent the atherosclerosis progression, and have a protective role after cerebral ischemia. What we still need to know? • Today, there is a need for conducting clinical trials to assess the role of montelukast in reducing cardiovascular risk and to further understand the mechanism of action behind this effect.

A dual CysLT1/2 antagonist attenuates allergen-induced airway responses in subjects with mild allergic asthma

BACKGROUND

The cysteinyl leukotrienes (cysLTs) play a key role in the pathophysiology of asthma. In addition to functioning as potent bronchoconstrictors, cysLTs contribute to airway inflammation through eosinophil and neutrophil chemotaxis, plasma exudation, and mucus secretion. We tested the activity of the dual cysLT_1/2 antagonist, ONO-6950, against allergen-induced airway responses.

METHODS

Subjects with documented allergen-induced early (EAR) and late asthmatic response (LAR) were randomized in a three-way crossover study to receive ONO-6950 (200 mg) or montelukast (10 mg) or placebo q.d. on days 1-8 of the three treatment periods. Allergen was inhaled on day 7 two hours postdose, and forced expiratory volume in 1 s (FEV₁ ) was measured for 7 h following challenge. Sputum eosinophils and airway hyperresponsiveness were measured before and after allergen challenge. The primary outcome was the effect of ONO-6950 vs placebo on the EAR and LAR.

RESULTS

Twenty-five nonsmoking subjects with mild allergic asthma were enrolled and 20 subjects completed all three treatment periods per protocol. ONO-6950 was well tolerated. Compared to placebo, ONO-6950 significantly attenuated the maximum % fall in FEV₁ and area under the %FEV₁ /time curve during the EAR and LAR asthmatic responses (P < 0.05) and allergen-induced sputum eosinophils. There were no significant differences between ONO-6950 and montelukast.

CONCLUSIONS

Attenuation of EAR, LAR, and airway inflammation is consistent with cysLT₁ blockade. Whether dual cysLT_1/2 antagonism offers additional benefit for treatment of asthma requires further study.

Asthma phenotypes: the intriguing selective intervention with Montelukast

Asthma is a heterogeneous disease, usually characterized by chronic airway inflammation and a variable course associated with various underlying mechanisms that can differ between individuals. Patients with asthma can therefore exhibit different phenotypes, a term used to define the observable characteristics of an organism resulting from the interaction between its genetic makeup and the environment. The heterogeneity of asthma has received a large amount of attention in the last few years in order to better tailor treatment according to the different clinical and biological phenotypes of the disease. Specific asthma phenotypes may require an approach to treatment sometimes different from that recommended by current guidelines, so a personalized approach to asthma pharmacotherapy is recommended. Growing evidence suggests that leukotrienes play an important role in the pathogenesis of bronchial asthma. The mechanisms of action of leukotriene-receptor antagonists theoretically predict a good response in some asthma “phenotypes”.In this article we have performed an analysis of the recent literature (controlled clinical trials and real-life studies) about a possible selective intervention with Montelukast in specific asthma phenotypes.

Therapeutic effect of budesonide/formoterol, montelukast and N-acetylcysteine for bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation

BACKGROUND

Bronchiolitis obliterans syndrome (BOS) after allogeneic hematopoietic stem cell transplantation (HSCT) is currently treated with systemic corticosteroids despite poor efficacy and side effects. This study investigated the therapeutic effect of budesonide/formoterol, montelukast and n-acetylcysteine, which are suggested as treatment options for BOS after HSCT.

METHODS

After diagnosis of BOS, 61 patients were treated with budesonide/formoterol, montelukast and n-acetylcysteine for 3 months. Pulmonary function test and COPD assessment test (CAT) were performed before and after the combination therapy. Therapeutic response was evaluated by changes in forced expiratory volume in 1 s (FEV1) or CAT score.

RESULTS

After 3 months of combination treatment, mean FEV1 increased by 220 mL (p < 0.001) and residual volume decreased by 200 mL (p =0 .005). Median CAT score also significantly decreased from 15.5 to 11.0 (p = 0.001). The overall response rate to combination therapy was 82 %. Comparing the no-response group and the response group, the forced vital capacity (% predicted) decline between pre-HSCT and BOS diagnosis was significantly greater in the response group (p = 0.036).

CONCLUSION

Combination treatment with budesonide/formoterol, montelukast and n-acetylcysteine significantly improved lung function and respiratory symptoms in patients with BOS after allogeneic HSCT without serious side effects.

Mepolizumab for the reduction of exacerbations in severe eosinophilic asthma

Asthma affects over 300 million people worldwide and is severe in 10% of sufferers. Severe asthma is associated with greater morbidity and mortality particularly as a consequence of frequent exacerbations. Advances in approaches to phenotype the heterogeneity of severe asthma has established the importance of eosinophilic inflammation and emerging new therapies are broadly designed to target T2-mediated eosinophilic inflammation with the aim to reduce exacerbation frequency. Here, we summarize the evidence that eosinophilic asthma is an important pheno(endo)type and identifies a group at risk of exacerbations; that established therapies reduce exacerbations, particularly in eosinophilic severe asthma; and discuss the role of mepolizumab, an IL-5 neutralising monoclonal antibody therapy, in reducing exacerbations in severe eosinophilic asthma compared to established and other emerging therapies.