Do biologics improve health outcomes in children with severe asthma? – A longitudinal cohort study

<bold>Introduction</bold>: Monoclonal antibody therapies (“biologics”) target inflammatory mediators in patients with severe asthma but are cost-prohibitive (≈$50,000/patient/year). Comparing health outcomes (effectiveness and safety) in children with severe asthma pre and post biologics will identify the best populations for use. <bold>Methods:</bold> We conducted a retrospective cohort study using the Observational Medical Outcomes Partnership (OMOP) Common Data Model system, a registry of electronic health records. We included children (12-18y) with confirmed <italic>Global Initiative for Asthma</italic> diagnosis of severe asthma, using any combination of biologics (omalizumab [OM], mepolizumab [ME], or dupilumab [DU]), treated at the Hospital for Sick Children (Toronto) from Jan 2014-Aug 2023. Health outcomes pre and post biologic (eg. emergency department [ED] visits, admissions) were compared. <bold>Results:</bold> We identified 16,187 asthma encounters across 5,889 unique patients with severe asthma. Forty-four (0.73%) patients were prescribed a unique biologic (DU n=14; OM n=29; ME n=5), of which 19 (44%) used with oral and 33 (77%) used with inhaled corticosteroids. Post biologics, mean ED visits and hospitalizations per patient decreased from 1.53 to 0.33 and 1.05 to 0.19, respectively (p<0.001). ED visits per patient person-year (PYR) declined from 1.57 to 0.27 (p<0.001), an incidence rate ratio (IRR) of 6.1 (95% CI 3.5-11.8; p<0.0001). Similarly, hospitalizations per patient PYR declined from 1.47 to 0.14 (p<0.001), an IRR of 10.4 (95% CI 4.9-25.6; p<0.0001). <bold>Conclusion</bold>: Children with severe asthma treated with biologics improved health outcomes, demonstrating effectiveness and potential in decreasing healthcare utilization.