AstraZeneca (NYSE: AZN) announced that tozorakimab met primary endpoints in two Phase III trials for chronic obstructive pulmonary disease. The OBERON and TITANIA trials showed the drug reduced the annualized rate of moderate-to-severe COPD exacerbations compared with placebo in former smokers and in the overall population including current and former smokers.

The trials enrolled 2,306 patients across both studies who had symptomatic COPD with a history of at least two moderate or one severe COPD exacerbations in the 12 months prior to enrollment. Patients received tozorakimab 300mg or placebo once every four weeks for 52 weeks on top of standard inhaled therapy.

Tozorakimab is a monoclonal antibody targeting interleukin-33 that inhibits signaling of both reduced and oxidized forms of IL-33. The drug was generally well tolerated with what the company described as a favorable safety profile.

COPD affects nearly 400 million people globally and ranks as the third leading cause of death worldwide. More than 50% of patients experience exacerbations even while on inhaled standard of care, according to the press release.

Two additional Phase III trials of tozorakimab in COPD, PROSPERO and MIRANDA, are ongoing with results expected in the first half of 2026. The drug is also being studied in Phase III trials for severe viral lower respiratory tract disease and Phase II trials for asthma.

The complete results from the OBERON and TITANIA trials will be presented at an upcoming medical meeting, according to the company statement.