Severe asthma in children: therapeutic considerations

New approaches in childhood asthma treatment

PURPOSE OF REVIEW

This review aims to summarize the most recent advances in asthma management, focusing on novel approaches to pediatric asthma.

RECENT FINDINGS

In recent years, the therapeutic tools for pediatric asthma have expanded significantly for both the nonsevere and severe forms. The use of anti-inflammatory treatment, even for the mildest cases, and the withdrawal of symptomatic bronchodilation as monotherapy have been included in the most recent guidelines. Also, different biological therapies have revolutionized the therapeutical approach for severe uncontrolled asthma in children and adolescents.

SUMMARY

With the expanding landscape of novel therapeutic approaches for pediatric asthma, further evidence is needed to help clinicians choose the best option for patients, particularly those with severe asthma. The identification of novel predictive biomarkers may also help pediatricians in selecting children and adolescents for innovative therapies.

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.

EAACI Biologicals Guidelines-Recommendations for severe asthma

Severe asthma imposes a significant burden on patients, families and healthcare systems. Management is difficult, due to disease heterogeneity, co-morbidities, complexity in care pathways and differences between national or regional healthcare systems. Better understanding of the mechanisms has enabled a stratified approach to the management of severe asthma, supporting the use of targeted treatments with biologicals. However, there are still many issues that require further clarification. These include selection of a certain biological (as they all target overlapping disease phenotypes), the definition of response, strategies to enhance the responder rate, the duration of treatment and its regimen (in the clinic or home-based) and its cost-effectiveness. The EAACI Guidelines on the use of biologicals in severe asthma follow the GRADE approach in formulating recommendations for each biological and each outcome. In addition, a management algorithm for the use of biologicals in the clinic is proposed, together with future approaches and research priorities.

Options of immunotherapeutic treatments for children with asthma

Introduction: Asthma is the most common chronic disease in children. Avoiding triggers, and pharmacologic treatment with short acting beta-agonist, inhaler corticosteroids and anti-leukotriene are often enough to obtain symptoms control. Nevertheless, there is a subset of children with severe asthma and poor symptom control despite maximal therapy. In these patients, anti-IgE and anti-IL5 monoclonal antibodies are suggested as the fifth step of Global Initiative for Asthma guidelines. Area covered: Immunotherapeutic treatments are now suggested for asthma management. This article will discuss the available evidence on allergen immunotherapy and biologic drugs in pediatric asthma treatment. Expert opinion: Previously published studies demonstrated a good efficacy and safety profile of Allergen Immunotherapy in patients with mild-moderate asthma and sensitization to one main allergen. New understanding of mechanisms underlying severe asthma inflammation has allowed the identifications of specific biomarkers guiding the clinician in the choice of patient specific drug. Among the suggested immunotherapeutic options, omalizumab (blocking IgE) remains the first choice for atopic 'early onset' asthma in patients aged over 6 years. Instead, mepolizumab (blocking the IL5 ligand) should be considered for 'eosinophilic' asthma. Other biologic drugs are under consideration but data on the pediatric population are still lacking.

Immunomodulation in Pediatric Asthma

Childhood asthma is actually defined as a heterogeneous disease, including different clinical variants and partially sharing similar immune mechanisms. Asthma management is mainly focused on maintaining the control of the disease and reducing the risk of adverse outcomes. Most children achieve good control with standard therapies, such as low doses of inhaled corticosteroids (ICS) and/or one or more controller. These medications are targeted to suppress bronchial inflammation and to restore airway responsiveness. However, they are not disease-modifying and do not specifically target inflammatory pathways of asthma; in addition, they are not significantly effective in patients with severe uncontrolled asthma. The aim of this review is to update knowledge on current and novel therapeutic options targeted to immunomodulate inflammatory pathways underlying pediatric asthma, with particular reference on biologic therapies.