Biological Therapies in Children and Adolescents with Severe Uncontrolled Asthma: A Practical Review

The Evolution of Scientific Knowledge in Childhood Asthma over Time: A Surprising History

Asthma is a disease that has been described since the times of Hammurabi. However, it is only since the 1960s that effective therapeutic strategies have been available. Pathogenic mechanisms underlying the disease have been deeply studied, contributing to creating a "patient-specific asthma" definition. Biological drugs have been approved over the last twenty years, improving disease management in patients with severe asthma via a "precision medicine-driven approach". This article aims to describe the evolution of scientific knowledge in childhood asthma, focusing on the most recent biological therapies and their indications for patients with severe asthma.

Effects of biological therapies on patients with Type-2 high asthma and comorbid obesity

Over 20 million adults and 6 million children in the United States (US) have asthma, a chronic respiratory disease characterized by airway inflammation, bronchoconstriction, and mucus hypersecretion. Obesity, another highly prevalent disease in the US, is a major risk factor for asthma and a significant cause of diminished asthma control, increased submucosal eosinophilia, and reduced quality of life. A large subgroup of these patients experiences severe symptoms and recurrent exacerbations despite maximal dosage of standard asthma therapies. In the past two decades, the development of biological therapies has revolutionized the field and advanced our understanding of type 2 inflammatory biomarkers. However, patients with obesity and comorbid asthma are not principally considered in clinical trials of biologics. Large landmark cluster analyses of patients with asthma have consistently identified specific asthma phenotypes that associate with obesity but may be differentiated by age of asthma onset and inflammatory cell profiles in sputum. These patterns suggest that biologic processes driving asthma pathology are heterogenous among patients with obesity. The biological mechanisms driving pathology in patients with asthma and comorbid obesity are not well understood and likely multifactorial. Future research needs to be done to elicit the cellular and metabolic functions in the relationship of obesity and asthma to yield the best treatment options for this multiplex condition. In this review, we explore the key features of type 2 inflammation in asthma and discuss the effectiveness, safety profile, and research gaps regarding the currently approved biological therapies in asthma patients with obesity.

Unanswered questions on the use of biologics in pediatric asthma

The emergence of biologic therapies for the management of asthma has been a revolutionary change in our capacity to manage this disease. Since the launch of omalizumab, several other biologics have been marketed or are close to being marketed, suggesting that a plethora of monoclonal antibodies can be expected in the coming years. This will facilitate the transition to the paradigm of personalized medicine, but on the other hand will decisively further complicate the choice of the most appropriate treatment, in the absence of reliable enough biological markers. For these reasons, along with the relatively short time of use with these treatments, there are recurrently arising questions for which there are not even moderately documented answers, and for which the only solution must be based, with all reservations, on the combination of indirect evidence and expertise. In this paper, we attempt to address such questions, providing relevant commentaries and considering the whole width of the evidence base.

Biologics and severe asthma in children

PURPOSE OF REVIEW

Severe asthma can carry significant morbidity and mortality for patients, and it places a burden on families and the healthcare system. Biologic agents have revolutionized the care of patients with severe asthma in recent years. Evidence surrounding some of these therapies is limited in the pediatric population, but recent studies show that they significantly improve asthma care when used appropriately. In this review, we discuss the biologic therapies currently approved to treat severe asthma in school-age children and adolescents.

RECENT FINDINGS

Randomized controlled trials have been published in support of biologics in children and/or adolescents. These therapies have been shown to reduce the annual rate of severe asthma exacerbations by at least 40-50%, and some up to about 70%. Improvements in asthma control, lung function, oral corticosteroid use, and quality of life have also been demonstrated, although these vary by agent. Furthermore, these therapies have reassuring safety profiles in pediatric patients.

SUMMARY

With three biologic agents approved for children ages 6-11 years and five approved for adolescents ages >12 years, it can be challenging to select one. The therapy should be chosen after careful consideration of the patient's asthma phenotype and biomarkers. Additional pediatric-specific clinical trials would be helpful in developing evidence-based guidelines on biologic therapies in this population.

Biologic Therapies for Moderate to Severe Asthma in the Pediatric Population: A Practice Update

Introduction

Asthma is a common childhood condition. Up until recent years, the mainstay of long-term control treatment has been inhaled corticosteroids. While inhaled corticosteroids are very effective for most children with asthma, with the introduction of biologic therapies, additional options now exist for children with uncontrolled moderate to severe asthma.

Purpose

The purpose of this Practice Update is to provide nursing professionals with a summary of the biologic therapies currently available for the pediatric population and, to describe when they are indicated for inclusion in the plan of care for children with moderate to severe asthma.

Conclusion

By properly diagnosing asthma, and, selecting and administering appropriate asthma therapies, nursing professionals can help children with moderate to severe asthma lead healthy and active lives.

Omalizumab and allergen immunotherapy for respiratory allergies: A mini-review from the Allergen-Immunotherapy Committee of the Italian Society of Pediatric Allergy and Immunology (SIAIP)

Although currently approved to treat severe asthma and chronic spontaneous urticaria, omalizumab has also been an effective and safe add-on treatment for other allergic diseases. Namely, omalizumab has been proposed to be used as add-on therapy in patients with allergic rhinitis and asthma and undergoing specific allergen immunotherapy (AIT). AIT is the only treatment that modifies the natural history of IgE-mediated diseases. This brief review summarizes the available evidence and controversies on the efficacy and safety of omalizumab combined with specific AIT.

Pediatric chronic spontaneous urticaria: a brief clinician's guide

INTRODUCTION

Chronic urticaria (CU) appears with daily or intermittent/recurrent wheals with/without angioedema for more than six weeks. When no specific eliciting factors are found, chronic urticaria is defined as spontaneous (CSU). Up to 50% of patients with CSU do not respond to therapy, leading to a prolonged disease course and the need for expensive therapies, impacting the quality of life (QoL) and healthcare resources.

AREAS COVERED

: Diagnosis of CSU is made when other potential causes of chronic urticaria are excluded. CSU therapy aims to achieve complete control of symptoms and normalization of QoL. Current treatment options for urticaria aim to target mast cell mediators such as histamine, or activators, such as autoantibodies. Guidelines recommend starting with second generation antihistamines (sgAHs) and adding omalizumab therapy if symptoms are not controlled. This review aims to provide a practical guide for CSU in the pediatric population.

EXPERT OPINION

: Treatment options for pediatric CSU are primarily based on adult data that have been extrapolated for children. Current guidelines should be re-evaluated based on pediatric data, new biological treatments, and the COVID-19 pandemic. Future research is needed to investigate strategies to personalize current treatments and identify potential predictive biomarkers.

Severe asthma in children: An official statement from Saudi Pediatric Pulmonology Association

In Saudi Arabia, the prevalence of pediatric asthma ranges between 8% and 25%. However, there are no sufficient data regarding severe asthma in childhood in Saudi Arabia. Therefore, a task force has been formed by the Saudi Pediatric Pulmonology Association which is a subsidiary group of the Saudi Thoracic Society and consists of Saudi experts with well-respected academic and clinical backgrounds in the fields of pediatric asthma as well as other respiratory diseases to write a consensus on definitions, phenotypes, and pathophysiology, evaluation, and management. To achieve this, the subject was divided into various sections, each of which was assigned to at least 2 experts. Without a central literature review, the authors searched the literature using their own strategies. To reach an agreement, the entire panel reviewed and voted on proposed findings and recommendations.

Severe Pediatric Asthma Therapy: Mepolizumab

There is a growing need for advanced treatment in children with persistent and severe asthma symptoms. As a matter of fact, between 2 and 5% of asthmatic children experience repeated hospitalizations and poor quality of life despite optimized treatment with inhaled glucocorticoid plus a second controller. In this scenario, mepolizumab, a humanized monoclonal antibody, has proven to be effective in controlling eosinophil proliferation by targeting interleukin-5 (IL-5), a key mediator of eosinophil activation pathways. Mepolizumab is approved since 2015 for adults at a monthly dose of 100 mg subcutaneously and it has been approved for patients ≥ 6 years of age in 2019. Especially in children aged 6 to 11 years, mepolizumab showed a greater bioavailability, with comparable pharmacodynamics parameters as in the adult population. The recommended dose of 40 mg every 4 weeks for children aged 6 through 11 years, and 100 mg for patients ≥ 12 years provides appropriate concentration and proved similar therapeutic effects as in the adult study group. A marked reduction in eosinophil counts clinically reflects a significant improvement in asthma control as demonstrated by validated questionnaires, reduction of exacerbation rates, and the number of hospitalizations. Finally, mepolizumab provides a safety and tolerability profile similar to that observed in adults with adverse events mostly of mild or moderate severity. The most common adverse events were headache and injection-site reaction. In conclusion, mepolizumab can be considered a safe and targeted step-up therapy for severe asthma with an eosinophilic phenotype in children and adolescents.

Novel therapeutic approaches targeting endotypes of severe airway disease

Introduction: Severe asthma and chronic rhinosinusitis (CRS), with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP), are heterogeneous diseases characterized by different mechanistic pathways (endotypes) and variable clinical presentations (phenotypes).Areas covered: This review provides the clinician with an overview of the prevalence and clinical impact of severe chronic upper and lower airways disease and suggests a novel therapeutic approach with biological agents with possible biomarkers. To select relevant literature for inclusion in this review, we conducted a literature search using the PubMed database, using terms 'severe airways disease' AND 'endotype' AND 'treatment.' The literature review was performed for publication years 2010-2020, restricting the articles to humans and English language publications.Expert opinion: The coronavirus disease (COVID-19) pandemic has brought forth many challenges for patients with severe airway disease and healthcare practitioners involved in care. These patients could have an increased risk of developing severe SARS-CoV-2 disease, although treatment with biologics is not associated with a worse prognosis. Eosinopenia on hospital admission plays a key role as a diagnostic and prognostic biomarker.