Semaglutide Linked to Up to 40% Fewer Asthma Attacks, Real-World Data Show

Semaglutide (Ozempic, Wegovy; Novo Nordisk), a glucagon-like peptide-1 (GLP-1) receptor agonist widely prescribed for type 2 diabetes (T2D) and obesity, was associated with a reduction in asthma attacks of nearly 40% and a reduction in chronic obstructive pulmonary disease (COPD) flare-ups of about 20% compared with sulfonylureas, according to real-world data presented at the European Respiratory Society (ERS) Congress 2026 in Barcelona, Spain. The findings represent one of the largest real-world investigations of GLP-1 receptor agonists in airways disease to date.^1,2

Study Design and Methodology

GLP-1 receptor agonists have not historically included asthma or COPD outcomes in clinical trials, despite preliminary evidence suggesting anti-inflammatory and lung-related benefits. To address this gap, investigators used UK electronic medical records to conduct 4 parallel new-user, active-comparator studies, each including between 20,000 and 22,000 patients, for a combined cohort of more than 80,000 individuals. Each study compared initiators of a specific GLP-1 receptor agonist—semaglutide, liraglutide (Victoza, Saxenda; Novo Nordisk), dulaglutide (Trulicity; Eli Lilly and Company), or exenatide (Byetta; Amylin Pharmaceuticals, Eli Lilly and Company)—with initiators of sulfonylureas, another class of diabetes medication.^1-4

Investigators applied doubly robust inverse probability of treatment weighting to adjust for confounding variables, including disease severity, body mass index, smoking status, eosinophil count, and comorbidities, before calculating weighted hazard ratios for airway exacerbations. The analysis also assessed whether effects varied by GLP-1 receptor agonist dose and by underlying respiratory diagnosis.²

Key Findings Across Airway Diseases

Across the pooled analysis, GLP-1 receptor agonist use overall was associated with a 14% reduction in asthma and COPD exacerbations relative to sulfonylureas. The magnitude of benefit varied by agent: semaglutide was linked to roughly a 30% to 38% reduction, exenatide to a 23% reduction, and dulaglutide to a 12% reduction.³

The effect was most pronounced for semaglutide in patients with asthma specifically, where use was associated with a reduction in asthma attacks approaching 40%, alongside a 20% reduction in COPD flare-ups. Investigators reported that changes in weight or glycemic control did not appear to modify these associations, suggesting the respiratory benefit may not be fully explained by weight loss or improved glucose management alone.^1,3

Expert Perspective on Clinical Implications

Chloe Bloom, MBChB, PhD, MSc, clinical associate professor in respiratory epidemiology at the National Heart & Lung Institute, Imperial College London, UK, noted that the results could carry meaningful implications for patients already eligible for GLP-1 receptor agonists due to obesity or type 2 diabetes, but she cautioned against extrapolating the findings into new prescribing behavior.¹

“For patients who already qualify for a GLP-1 receptor agonist because of diabetes or obesity, these findings suggest there may be an additional respiratory benefit. But these drugs should not replace standard inhaled asthma or COPD treatments,” Bloom said in an interview with Pharmacy Times.

Bloom noted that the divergent findings between asthma and COPD raise questions the current data cannot yet answer.

“There are plausible biological reasons why the effect may differ between asthma and COPD, but our study cannot explain the mechanism. We need mechanistic studies and randomized trials to understand whether the difference is real and why,” she said.

Looking ahead, Bloom said confirmatory trials will be essential before the findings could meaningfully shift clinical practice.

“We now need randomized trials to confirm whether GLP-1 receptor agonists reduce exacerbations, identify which patients benefit most, and determine whether effects differ by airway disease or by drug. That evidence would be needed before they could influence respiratory guidelines,” she added.

Alexander Mathioudakis, MD, PhD, chair of the ERS Group on Airway Pharmacology and Treatment and senior lecturer in respiratory medicine at the University of Manchester, who was not involved in the research, called the analysis notable for its scale and for being among the first to examine differential effects across individual GLP-1 agents. He said the results strengthen the case for incorporating respiratory outcomes, such as asthma attacks, COPD exacerbations, lung function, and quality-of-life measures, into future trials of metabolic therapies.¹

Limitations and Next Steps

The data were presented as a conference abstract at European Respiratory Society (ERS) Congress 2026 and have not yet undergone peer review or publication in a journal. As an observational analysis, the study cannot establish causality, and independent experts have emphasized that randomized controlled trials incorporating respiratory endpoints are needed to confirm whether GLP-1 receptor agonists genuinely prevent asthma and COPD exacerbations.^3,5

For pharmacists, the findings underscore a growing intersection between metabolic and respiratory care and may inform future counseling conversations for patients with overlapping diabetes, obesity, and airway disease—though current prescribing guidance for GLP-1 receptor agonists remains unchanged pending confirmatory trial data.⁴

REFERENCES

1. Weight loss injection semaglutide can reduce asthma attacks by up to 40 percent. European Respiratory Society. September 8, 2026. https://www.ersnet.org/news-and-features/news/weight-loss-injection-semaglutide-can-reduce-asthma-attacks-by-up-to-40-per-cent/

2. Johnson V. Semaglutide Cuts Asthma Attacks by up to 40% in Real-World Study. HCPLive. September 8, 2026. Accessed September 18, 2026. https://www.hcplive.com/view/semaglutide-cuts-asthma-attacks-by-up-to-40-real-world-study

3. Semaglutide tied to fewer asthma, COPD exacerbations. Respiratory Therapy. September 14, 2026. Accessed September 18, 2026. https://www.healio.com/news/allergy-asthma/20260914/semaglutide-associated-with-lower-exacerbation-risks-in-asthma-copd

4. Harley S. Semaglutide linked to 20% fewer COPD flare-ups and nearly 40% fewer asthma attacks. September 7, 2026. Accessed September 18, 2026. https://medicalxpress.com/news/2026-09-semaglutide-linked-copd-flare-ups.html