Biologics in Children with Allergic Diseases

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.

Novel Lung Growth Strategy with Biological Therapy Targeting Airway Remodeling in Childhood Bronchial Asthma

Anti-inflammatory therapy, centered on inhaled steroids, suppresses airway inflammation in asthma, reduces asthma mortality and hospitalization rates, and achieves clinical remission in many pediatric patients. However, the spontaneous remission rate of childhood asthma in adulthood is not high, and airway inflammation and airway remodeling persist after remission of asthma symptoms. Childhood asthma impairs normal lung maturation, interferes with peak lung function in adolescence, reduces lung function in adulthood, and increases the risk of developing chronic obstructive pulmonary disease (COPD). Early suppression of airway inflammation in childhood and prevention of asthma exacerbations may improve lung maturation, leading to good lung function and prevention of adult COPD. Biological drugs that target T-helper 2 (Th2) cytokines are used in patients with severe pediatric asthma to reduce exacerbations and airway inflammation and improve respiratory function. They may also suppress airway remodeling in childhood and prevent respiratory deterioration in adulthood, reducing the risk of COPD and improving long-term prognosis. No studies have demonstrated a suppressive effect on airway remodeling in childhood severe asthma, and further clinical trials using airway imaging analysis are needed to ascertain the inhibitory effect of biological drugs on airway remodeling in severe childhood asthma. In this review, we describe the natural prognosis of lung function in childhood asthma and the risk of developing adult COPD, the pathophysiology of allergic airway inflammation and airway remodeling via Th2 cytokines, and the inhibitory effect of biological drugs on airway remodeling in childhood asthma.

Monoclonal Antibodies in Treating Chronic Spontaneous Urticaria: New Drugs for an Old Disease

Background: H1-antihistamines (H1AH) represent the current mainstay of treatment for chronic spontaneous urticaria (CSU). However, the response to H1AH is often unsatisfactory, even with increased doses. Therefore, guidelines recommend the use of omalizumab as an add-on treatment in refractory CSU. This paved the way for the investigation of targeted therapies, such as monoclonal antibodies (mAbs), in CSU. Methods: A literature review was conducted including papers published between 2009 and 2022 and ongoing trials about the efficacy and safety of mAbs as treatment for CSU. Results: Twenty-nine articles, a trial with preliminary results, and seventeen ongoing or completed clinical trials on the use of mAbs in CSU were included. Randomized controlled trials (RCTs), meta-analysis, and real-life studies have proven the effectiveness and safety of omalizumab as a third-line treatment in refractory CSU. However, a percentage of patients remain unresponsive to omalizumab. Therefore, other mAbs, targeting different pathways, have been used off-label in case series and others are under investigation in RCTs. Most of them have showed promising results. Conclusions: Omalizumab remains the best choice to treat refractory CSU. Although results from other mAbs seem to be encouraging to achieve symptom control in refractory CSU, thus improving patients’ QoL, RCTs are needed to confirm their effectiveness and safety.

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 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.

Immunological Targets of Biologic Drugs in Allergic Skin Diseases in Children

Atopic dermatitis and urticaria are two invalidating skin disorders that are very common in children. Recent advances in the understanding of their specific intracellular molecular pathways have permitted the development of precise biological molecules, targeting inflammatory mediators and arresting the pathogenetic pathways of skin diseases. Many biologics with promising results have been studied, although few are currently approved in children. In this review, we aim to provide the latest evidence about the use, indications, efficacy and safety of biologic therapies to treat atopic dermatitis and chronic urticaria in children and adolescents.

Monoclonal Antibodies in Treating Food Allergy: A New Therapeutic Horizon

Food allergy (FA) is a pathological immune response, potentially deadly, induced by exposure to an innocuous and specific food allergen. To date, there is no specific treatment for FAs; thus, dietary avoidance and symptomatic medications represent the standard treatment for managing them. Recently, several therapeutic strategies for FAs, such as sublingual and epicutaneous immunotherapy and monoclonal antibodies, have shown long-term safety and benefits in clinical practice. This review summarizes the current evidence on changes in treating FA, focusing on monoclonal antibodies, which have recently provided encouraging data as therapeutic weapons modifying the disease course.

Biologic Therapy and Severe Asthma in Children

Severe asthma is a heterogeneous, complex and chronic disease widespread in the pediatric population. According to the recent findings about the different endotypes of asthma in children, each one characterized by specific intracellular molecular pathways, several innovative biologic therapies have been developed. Due to their precise ability to target specific inflammatory type 2 mediators, biologics have revolutionized the care of chronic allergic diseases in the pediatric and adult population. In this review, we aim to provide the latest evidence about the use, indications, efficacy and safety of biologic therapies to treat severe asthma 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.

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

Severe uncontrolled asthma is a complex and heterogeneous disease. A multidisciplinary assessment is required to correctly identify and manage children and adolescents with severe asthma because they may require strict monitoring and additional treatment with advanced targeted therapies. Recent research efforts have focused on identifying epidemiologic, clinical, and molecular mechanisms that underlie severe asthma, leading to the recognition of different phenotypes and endotypes and identifying biomarkers able to predict the response to biologic therapies. Additional progress has occurred by introducing biological therapies that have revolutionized the care of chronic allergic diseases in the adult and pediatric population. In this review, we briefly summarized the current literature on biological therapies to treat severe asthma in children and adolescents.

An update on biological therapies for pediatric allergic diseases

Allergic diseases represent a global health burden. Patients with allergic diseases may experience disability, reduced quality of life and productivity, emotional distress, and social restrictions, especially in the most severe cases. Current advances in unveiling the pathogenesis of allergic disorders have paved the way for the development of novel therapeutic strategies. Biological drugs have been widely studied in pediatric allergic asthma, with strong evidence of efficacy and safety. Moreover, promising results derive from studies on other conditions such as atopic dermatitis, chronic spontaneous urticaria, and food allergy. This review analyzes recent evidence on the role of biologic therapies for allergic diseases, focusing on the pediatric age.

Nationwide Multicenter Study of Eosinophilic Esophagitis in Korean Children

PURPOSE

In East Asian countries, there are only a few epidemiologic studies of eosinophilic esophagitis (EoE) and no studies in children. We investigated the incidence and compared the clinical characteristics of EoE and eosinophilic gastroenteritis involving the esophagus (EGEIE) in Korean children.

METHODS

A total of 910 children, who had symptoms of esophageal dysfunction, from 10 hospitals in Korea were included. EoE was diagnosed according to diagnostic guidelines and EGEIE was diagnosed when there were >15 eosinophils in the esophagus per high power field (HPF) and >20 eosinophils per HPF deposited in the stomach and duodenum with abnormal endoscopic findings.

RESULTS

Of the 910 subjects, 14 (1.5%) were diagnosed with EoE and 12 (1.3%) were diagnosed with EGEIE. Vomiting was the most common symptom in 57.1% and 66.7% of patients with EoE and EGEIE, respectively. Only diarrhea was significantly different between EoE and EGEIE (p=0.033). In total, 61.5% of patients had allergic diseases. Exudates were the most common endoscopic findings in EoE and there were no esophageal strictures in both groups. The median age of patients with normal endoscopic findings was significantly younger at 3.2 years, compared to the median age of 11.1 years in those with abnormal endoscopic findings (p=0.004).

CONCLUSION

The incidence of EoE in Korean children was lower than that of Western countries, while the incidence of EGEIE was similar to EoE. There were no clinical differences except for diarrhea and no differences in endoscopic findings between EoE and EGEIE.

Current and emerging biologic therapies for allergic rhinitis and chronic rhinosinusitis

Introduction: Allergic rhinitis and chronic rhinosinusitis, with and without nasal polyps, are the most common chronic inflammatory diseases of the upper airways. They both cause relevant respiratory symptoms and a substantial detriment to patients' quality of life, mainly in uncontrolled and severe patients.Areas covered: This review aims to present the most recent evidence on current and emerging biologic therapies for allergic rhinitis and chronic rhinosinusitis and discuss their potential implementation in clinical practice. To select relevant literature for inclusion in this review, we conducted a literature search using the PubMed database, using terms 'biologics OR biological agents', 'allergic rhinitis' and 'chronic rhinosinusitis'. The literature review was performed for publication years 2009-2019, restricting the articles to humans and English language publications.Expert opinion: Biological therapies represent a potential step forward in providing individualized care for all patients with uncontrolled severe upper airway diseases. Biologics recently showed promising results for the treatment of severe uncontrolled allergic rhinitis and chronic rhinosinusitis with nasal polyps with or without associated asthma. Endotyping inflammatory pathways and identifying related biomarkers remain the major challenge for positioning biologics in the care pathway of chronic respiratory diseases.