AstraZeneca COPD Drug Cuts Exacerbations as FDA Priority Review Nears

Tozorakimab significantly reduced COPD exacerbations in the Phase III OBERON and TITANIA trials, cutting moderate-to-severe events by 29% and 34% among former smokers and about 30% overall. Benefits were consistent across eosinophil levels, lung-function severity and smoking status. The FDA granted the investigational anti-IL-33 drug priority review , with a regulatory decision expected in the first quarter of 2027. AstraZeneca estimates roughly 6 million COPD patients could be eligible for a biologic by 2030. Safety was generally balanced with placebo, although injection-site reactions were more common and major cardiovascular events showed a slight numerical imbalance. Quality-of-life results missed statistical significance, while symptom improvements and some lung-function gains were reported.

Astrazeneca NYSE: AZN presented Phase III data for tozorakimab in chronic obstructive pulmonary disease, or COPD, at the 2026 European Respiratory Society Congress in Barcelona, reporting statistically significant reductions in moderate-to-severe exacerbations across two trials and across a broad range of patient subgroups. The company said the FDA has granted priority review for tozorakimab, an investigational anti-IL-33 monoclonal antibody, with a Prescription Drug User Fee Act action date in the first quarter of 2027.

The trials evaluated tozorakimab given subcutaneously every four weeks versus placebo, on top of optimized guideline-based COPD treatment, in patients with a history of exacerbations. The primary endpoint measured the annualized rate of moderate-to-severe exacerbations among former smokers. AstraZeneca reported reductions of 29% in OBERON and 34% in TITANIA for that population. In the overall population of current and former smokers, the company reported exacerbation-rate reductions of 30% and 29%, respectively.

The trial population included patients across blood-eosinophil levels, including approximately 40% with fewer than 150 eosinophils, according to Sciurba. About 20% of participants had severe airflow limitation, defined as less than 30% predicted post-bronchodilator FEV1. In a pooled analysis, Sciurba said the treatment effect was consistent across eosinophil levels, lung-function severity and smoking status. The company cited a 23% reduction in exacerbations among patients with eosinophil counts below 150 cells per microliter, a population for which it said no biologic is currently approved. It also reported reductions of 34% among patients at or above 150 cells per microliter and 43% among those at or above 300 cells per microliter. Severe exacerbations involving emergency-department visits or hospitalization declined by 36% in one trial and 33% in the other, according to the presentation.

The St. George’s Respiratory Questionnaire, a quality-of-life measure, did not achieve statistical significance in the hierarchical testing sequence. Sciurba said the Exacerbations of Chronic Pulmonary Disease Tool-Respiratory Symptoms score, or E-RS, showed statistically significant symptom improvements in both studies, although those findings were nominally significant following the missed St. George’s endpoint. FEV1 improved by roughly 25 cubi...