An Update on Biologics in Pediatric Asthma: A Canadian Perspective

Authors

  • Jacob McCoy, MD Division of Respiratory Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Canada
  • Padmaja Subbarao, MD Division of Respiratory Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Canada

DOI:

https://doi.org/10.58931/cait.2025.5181

Abstract

Asthma is one of the most common chronic diseases in Canada, affecting approximately 11% of Canadians. Severe asthma, estimated to affect 5–10% of patients with asthma, is associated with a significant burden of disease‑related morbidity. In adults, typical management strategies include using combinations of inhaled corticosteroids, long-acting beta agonists, leukotriene receptor antagonists, long-acting muscarinic antagonists, and oral corticosteroids. However, in pediatric cases, particularly young children, our medication options are more limited. Although inhaled corticosteroids are effective for the majority of mild-to-moderate asthma cases, their efficacy in non-atopic asthma is limited.  Furthermore, using inhaled corticosteroids at moderate-to-high doses can impair linear growth and lead to adrenal suppression. Given our growing recognition of asthma as a heterogenous disease, with multiple disease endotypes driven by distinct inflammatory pathways, there is an increasing demand for targeted therapies, particularly for patients with ongoing, uncontrolled disease (Figure 1). Type 2 (T2) high inflammation, characterized by elevated levels of IgE, interleukin (IL)-4, IL-5, and IL-13, alongside eosinophilia and atopy, remains the most well-defined endotype in school-age children and youth. With the advent of biologic medications, targeting T2‑high inflammatory pathways has become a critical component for managing uncontrolled, moderate‑to-severe asthma in children. This approach aims to improve treatment response and reduce adverse effects. This review will explore the biologic therapies currently available in Canada for moderate-to-severe pediatric asthma, discuss key considerations in selecting the optimal biologic, and outline future research directions to inform the optimal timing for initiating and discontinuing biologic treatments.

Author Biographies

Jacob McCoy, MD, Division of Respiratory Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Canada

Dr. Jacob McCoy is a pediatric respirologist, currently completing further subspecialty training in severe asthma, and his PhD in Clinical Epidemiology and Health Care Research at the University of Toronto. 

Padmaja Subbarao, MD, Division of Respiratory Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Canada

Dr. Subbarao is a Clinician-Scientist in Pediatric Respiratory Medicine specializing clinically in severe asthma. She is the Director of the CHILD Study and holds a CRC Tier 1 Chair in Pediatric Asthma and Lung Health at the University of Toronto. She is also the Co-Lead of Precision Child Health and Associate Chief, Clinical Research at the RI. Trained in both Epidemiology and infant and preschool lung physiology, she holds appointments as a Senior Scientist in Translational Medicine and as a Professor in the Departments of Pediatrics, Physiology and in the Dalla Lana School of Public Health.

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Published

2025-06-02

How to Cite

1.
McCoy J, Subbarao P. An Update on Biologics in Pediatric Asthma: A Canadian Perspective. Can Allergy Immunol Today [Internet]. 2025 Jun. 2 [cited 2025 Jun. 29];5(1):34–39. Available from: https://canadianallergyandimmunologytoday.com/article/view/5-1-McCoy_et_al

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