AstraZeneca’s Asthma Drug Fails in ‘Smoker’s Lung’ Study

AstraZeneca (AZN.L) announced on Wednesday that its asthma treatment, Fasenra, failed to meet its primary goal in a late-stage trial for patients with chronic obstructive pulmonary disease (COPD)—a major setback in efforts to address this serious lung condition.

The drugmaker stated that Fasenra did not significantly reduce the rate of COPD exacerbations compared to a placebo, and added that it will further analyze the full set of trial data to better understand the results.

Fasenra is the second best-selling medicine in AstraZeneca’s respiratory and immunology portfolio. It generated $920 million in sales in the first half of 2025, an 18% increase compared to the same period last year.

Sharon Bar, an executive at AstraZeneca, said, “COPD, which remains one of the leading causes of death worldwide, is a complex and heterogeneous disease. We are advancing other promising approaches in our pipeline to address the unmet needs of patients.”

COPD, often referred to as “smoker’s lung,” is also being targeted by AstraZeneca’s other treatments, including its triple-combination inhaler Breztri Aerosphere and the experimental therapy tozorakimab.

The patients enrolled in the Fasenra trial were current or former smokers who were receiving existing treatments for COPD and had experienced at least two flare-ups in the past year.

In addition to the COPD trial results, AstraZeneca announced that its rare disease drug, Safinelo, successfully achieved its primary endpoint in a late-stage study, significantly reducing disease activity in patients with systemic lupus erythematosus, a chronic autoimmune disorder.