Tozorakimab showed clinically meaningful benefits across blood eosinophil thresholds
- Full results published in the New England Journal of Medicine and presented at the European Respiratory Society Congress 2026
- Tozorakimab Biologics License Application accepted under Priority Review in US forpatients with COPD
Full results from the positive Phase III OBERON and TITANIA trials showed that tozorakimab is the first biologic to demonstrate statistically significant and highly clinically meaningful efficacy in reducing moderate and severe exacerbations in a broad population of patients with chronic obstructive pulmonary disease (COPD) still experiencing exacerbations while on inhaled standard of care.
The trials included former and current smokers, and patients across all blood eosinophil counts (BEC) and all stages of lung function severity.
Tozorakimab 300mg, administered once every four weeks, demonstrated a reduction in moderate and severe COPD exacerbations in the primary population of former smokers by 29% (OBERON) and 34% (TITANIA), and in the overall population of current and former smokers by 30% (OBERON) and 29% (TITANIA) compared with placebo while on inhaled standard of care.
In a pooled analysis of OBERON and TITANIA, tozorakimab also demonstrated clinically meaningful reductions in moderate and severe exacerbations in all prespecified patient subgroups including those defined by BEC in the overall population.
In addition, patients on tozorakimab with a baseline BEC of less than 150 achieved a 23% reduction in moderate and severe exacerbations; patients at or above 150 achieved a 34% reduction; and patients at or above 300 achieved a 43% reduction.
Frank Sciurba, MD, FCCP, Professor of Pulmonary and Critical Care Medicine, University of Pittsburgh, Chief Investigator of the LUNA program, said: “The OBERON and TITANIA trials mark the first time we have seen a biologic in COPD achieve efficacy in a broad population across blood eosinophil thresholds, including in patients with baseline eosinophils below 150, and irrespective of smoking status. These unprecedented results, along with its favorable safety profile, underscore tozorakimab’s potential as an innovative treatment for the millions of people living with COPD who remain at risk despite treatment with inhaled standard of care.”
Sharon Barr, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said: “Today’s groundbreaking tozorakimab results, from two replicate trials, set a new standard for COPD treatment outcomes in a broad population of patients. AstraZeneca has clinically validated the novel approach of targeting the signalling of the two forms of IL-33 to both decrease inflammation and disrupt the cycle of mucus dysfunction. With our FDA Priority Review, we look forward to bringing this treatment to patients as quickly as possible.”
These data were presented on 8 September 2026 as a late-breaker oral presentation in the ALERT-2 plenary session at the European Respiratory Society Congress and were simultaneously published in the New England Journal of Medicine.
In a separate poster presentation at the ERS Congress 2026, AstraZeneca presented results from an integrated analysis of OBERON and TITANIA that demonstrated a reduction in patients’ mucus plug score.3 Tozorakimab is the first biologic to reduce mucus plugging in a broad population of COPD patients.3 Mucus plug score is an important emerging outcome measure, as mucus plugs have been associated with worse outcomes in COPD.4
Tozorakimab was generally well tolerated with a favorable safety profile. The only adverse drug reaction was injection-site reaction.1,2
Tozorakimab is a potential first-in-class monoclonal antibody targeting interleukin-33 (IL-33) that uniquely inhibits the signalling of the reduced and oxidised forms of IL-33, offering the potential to both reduce inflammation and disrupt the cycle of mucus dysfunction that contribute to COPD worsening.5-9
The Biologics License Application for tozorakimab 300mg, administered once every four weeks, has been accepted for Priority Review by the US Food and Drug Administration as an add-on maintenance treatment for adult patients with COPD. The Prescription Drug User Fee Act date is anticipated during the first quarter of 2027 following use of a Priority Review voucher. Tozorakimab is currently under regulatory review for the treatment of COPD in major markets, including the EU and China. It is also being studied in a Phase II trial in severe asthma and a Phase III trial in severe viral lower respiratory tract disease.10,11
Clinical Professor in Respiratory Medicine at the University of Leicester, and Respiratory Theme Lead at the NIHR BRC Leicester, Chris Brightling, said: “One of the challenges of COPD is that it is a disease that can look very different from one patient to the next. What makes the OBERON and TITANIA findings particularly important is that we saw meaningful reductions in exacerbations across a broad population of COPD patients, including across all blood eosinophil thresholds. For clinicians, the prospect of a biologic that could benefit a broad patient population represents an important development in how we think about treating COPD.
“COPD exacerbations can have a devastating impact on patients – potentially leading to hospitalisation, loss of lung function and even premature death. That’s why these results from OBERON and TITANIA are so important – tozorakimab delivered clinically meaningful reductions in exacerbations across a broad group of COPD patients. For a disease that affects nearly half a billion people, these results mean tozorakimab has the potential to be a meaningful treatment for so many patients.”
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For the full paper please visit: Tozorakimab to Prevent COPD Exacerbations | New England Journal of Medicine