Real-World Effectiveness of Tezepelumab in Severe Asthma: A 12-Month Canadian Cohort Study
In brief
Adults on tezepelumab had 92% fewer asthma flares over 12 months
In a two-centre Canadian cohort of 75 adults with severe asthma, exacerbations requiring oral steroids fell from 2.23 to 0.19 per patient-year after starting tezepelumab; emergency visits or hospitalizations also dropped by 87%. Lung function and breathlessness improved, but the retrospective before-and-after study cannot establish that tezepelumab alone caused the changes.
- Journal
- Journal of asthma and allergy (Q1)
- Published
- 16 October 2026
- Study design
- Retrospective cohort
- Evidence level
- Level 4, Very Low (CEBM 4)
- Authors
- Mathieu D Saint-Pierre, Samih Agaybi, Catherine B Charron, Jean-Grégoire Leduc
- PMID
- 42904223
- DOI
- 10.2147/JAA.S652986
Why clinicians should know about it
- Picked for Immunology and Allergy (paper of the day, 25 October 2026): Real-world effectiveness of biologic therapy for severe asthma
Abstract
RATIONALE: Many patients with asthma remain poorly controlled despite high-intensity inhaled therapy. Tezepelumab, a monoclonal antibody targeting thymic stromal lymphopoietin, has shown benefit in both type 2 (T2)-high and T2-low asthma. Real-world evidence in diverse clinical populations remains limited. OBJECTIVE: To evaluate the real-world effectiveness of tezepelumab in adults with severe asthma, including changes in exacerbations, lung function, and dyspnea across clinically relevant subgroups. METHODS: We retrospectively identified adults with severe asthma who initiated tezepelumab between July 2022 and April 2025 at two centres in Ontario, Canada. Patients who completed at least 12 months of therapy were included (n=75). The primary outcome was the comparison of asthma exacerbation rates (AER) requiring oral corticosteroids during the 12 months before and after treatment initiation. Secondary outcomes included AER stratified by smoking history, chronic obstructive pulmonary disease diagnosis, prior asthma biologic use, blood eosinophil count, and evidence of T2 inflammation. Changes in post-bronchodilator forced expiratory volume in 1 second (FEV1) and modified Medical Research Council (mMRC) dyspnea scores from baseline to 12 months were also reviewed. MEASUREMENTS AND MAIN RESULTS: In the overall patient population, AER decreased from 2.23 to 0.19 exacerbations per patient-year (rate ratio, 0.08; 95% CI, 0.04, 0.14), corresponding to a 92% reduction. Exacerbations requiring an ED visit or hospitalization decreased by 87%. Substantial reductions in AER were observed across the assessed patient subgroups. Overall, mean FEV1 increased by 0.15 L; FEV1 % predicted increased by 7 percentage points. Mean mMRC score also decreased from 1.8 to 0.7. Of the 6 patients receiving maintenance oral corticosteroids at initiation of tezepelumab, 5 were able to discontinue therapy. CONCLUSION: In this real-world Canadian cohort, 12 months of tezepelumab was associated with substantial reductions in asthma exacerbations and improvements in lung function and dyspnea across diverse clinical subgroups.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.