WILMINGTON, Del. — A new experimental drug, tozorakimab, significantly reduced flare-ups in patients with chronic obstructive pulmonary disease (COPD) in two large Phase III clinical trials, offering what researchers describe as a potential new approach to treating the disease.
Results from the OBERON and TITANIA trials showed the drug lowered the annual rate of moderate-to-severe COPD exacerbations compared with placebo. The benefit was seen both in former smokers — the primary study group — and across a broader population that included current smokers, patients with varying lung function, and all levels of blood eosinophils.
Tozorakimab was also generally well tolerated, with researchers reporting a favorable safety profile.
The drug is a monoclonal antibody designed to target interleukin-33 (IL-33), a protein involved in inflammation. Unlike other treatments, it blocks both reduced and oxidized forms of IL-33, a mechanism researchers say may help reduce inflammation while also addressing mucus dysfunction — two major drivers of COPD progression.
In both trials, patients continued their standard inhaled therapies while receiving either tozorakimab 300 mg or a placebo every four weeks.
COPD affects nearly 400 million people worldwide and is the third leading cause of death globally. Despite standard treatments, more than half of patients continue to experience exacerbations, which increase the risk of hospitalization, cardiovascular complications, and death.
“These trial results suggest that targeting the IL-33 pathway with tozorakimab delivers meaningful clinical benefit in a trial representing a broad COPD population, independent of smoking status and eosinophilic levels,” said Frank Sciurba, M.D., FCCP, Professor of Pulmonary and Critical Care Medicine at the University of Pittsburgh and chief investigator of the LUNA program. “COPD has long been a difficult-to-treat disease with inherent heterogeneity and significant unmet need, with up to half of patients worldwide at risk of exacerbations, hospitalizations, cardiopulmonary events, and death — underscoring the importance of these results for advancing COPD science.”
Sharon Barr, Executive Vice President of BioPharmaceuticals R&D at AstraZeneca, said the findings mark a key milestone.
“Today’s tozorakimab results deliver the first two confirmatory Phase III trials for an IL-33 biologic, which is a major scientific advancement in COPD, the world’s third leading cause of death,” Barr said. “Tozorakimab works in a fundamentally different way from other biologics, inhibiting the signaling of the reduced and oxidized forms of IL-33 to both decrease inflammation and disrupt the cycle of mucus dysfunction that are key disease drivers in COPD.”
