Semaglutide, alone among GLP-1s, tied to fewer asthma attacks

Clinical takeaway: For patients with asthma who qualify for a GLP-1 on diabetes or obesity grounds, the comorbidity may inform agent selection, with semaglutide the only one associated with fewer exacerbations. 

Obesity and type 2 diabetes cluster with asthma and COPD. Each raises the risk of exacerbation on top of an airway disease. GLP-1 receptor agonists now reach a substantial share of patients living with that overlap, which means clinicians are already choosing among these agents for people whose lungs may have a stake in the decision. Until now there has been almost nothing to consult on that point, because asthma and COPD outcomes have never been captured in GLP-1 trials. 

The evidence here speaks to GLP-1 receptor agonists alone. Dual GIP/GLP-1 agonists such as tirzepatide were outside the comparison. What real-world data had previously shown was a class-level pattern: observational studies reported fewer exacerbations in patients on GLP-1 therapy, with anti-inflammatory activity beyond weight loss proposed as the reason. 

Whether individual agents differ, whether dose matters, and whether asthma and COPD respond alike had not been examined, and a dose-dependent mechanism would predict exactly such differences, since the agents vary considerably in potency. A set of parallel real-world comparisons built to test each agent separately now supplies early answers. 

Across the four comparisons, only semaglutide was associated with fewer airway exacerbations. Liraglutide, dulaglutide, and exenatide showed no association in either disease. Among patients who started semaglutide, exacerbations ran 24% lower than among patients started on a sulfonylurea. 

People who started semaglutide were estimated to have an 80% lower risk of an asthma attack during follow-up than those who started a sulfonylurea, though the exact size of the difference remains uncertain. In COPD, the estimated reduction was 24% but the finding was less conclusive. Both semaglutide dose groups showed a lower estimated risk of exacerbation, with a larger difference in the combined medium/high-dose group. 

The four studies drew on UK electronic medical records, each comparing new users of one GLP-1 receptor agonist against new users of sulfonylureas in patients with asthma or COPD; the semaglutide cohort numbered 22,537. Weighting adjusted for disease severity, BMI, smoking, eosinophils, and comorbidities. The findings were presented at the European Respiratory Society Congress in Barcelona and have not been peer reviewed. 

The researchers are clear that these findings should not change treatment on their own. Patients should not start a GLP-1 for their lungs outside current prescribing guidance. What could change practice is a trial with respiratory endpoints, which has not been conducted. This study makes that potential trial easier to design than it was before: it points to a specific drug, a specific patient group, and a specific outcome to test. 

"This is one of the largest real-world studies to investigate GLP-1 receptor agonists and airways disease, and one of the first to examine whether effects differ between individual GLP-1 receptor agonists," said Alexander Mathioudakis, chair of the European Respiratory Society's Group on Airway Pharmacology and Treatment and senior lecturer in respiratory medicine at the University of Manchester, who was not involved in the research.

"It highlights the need to consider metabolic health as part of respiratory care. It also supports the case for including respiratory outcomes, such as asthma attacks and COPD exacerbations, in future trials of metabolic therapies," he added. "We need clinical trials that include respiratory outcomes, such as asthma attacks, COPD exacerbations, lung function, symptoms and quality of life, to determine whether metabolic treatments could become part of a broader, more personalised approach to managing airways disease." 

Source: Lee B, et al. (2026 Sep 8) European Respiratory Society Congress 2026. The differential effects of GLP-1 based therapies in airways disease