The role of neutrophilic inflammation — and why it's a target for a new treatment strategy

For decades, clinicians have known that the inflammation seen in bronchiectasis airways is predominantly neutrophilic, Sala explained. Neutrophils are a type of white blood cell that normally serve a protective, first-line-of-defense role against infection. In bronchiectasis, however, neutrophils tend to linger in the airways longer than they should, releasing a pro-inflammatory environment. Research going back several decades has tied this persistent neutrophilic inflammation — and specifically the release of neutrophilic elastase — to more frequent exacerbations, creating what Sala described as "too much of a good thing."

Despite that understanding, the available treatment toolkit remains narrow. Before August 2025, management options were limited to bronchodilators such as albuterol, hypertonic saline nebulizers to loosen mucus, antibiotics for active infection, and airway clearance techniques such as vest therapy. Azithromycin, a macrolide, has been the only drug used specifically for its anti-inflammatory effect, rather than as an antibiotic. Sala noted this reflects a broader lack of innovation in precisely targeting the inflammatory process that underlies the disease.

Asked what success looks like under a more inflammation-targeted approach, Sala pointed to quality of life as the overarching goal: fewer hospitalizations, fewer office visits, less avoidance of social settings due to cough, and maintained body weight. Exacerbations remain a major focus because they are often what brings patients to medical attention, but clinicians also track whether the disease is progressing radiographically — whether CT scans show worsening bronchiectasis over time. Ultimately, he said, success is measured by quality of life, fewer flares, and slower disease progression.