Low-Dose Endotoxin Inhalation In Healthy Volunteers: A Challenge Model For Early Clinical Drug Development Of Novel Anti-Inflammatory Compounds

Inhaled endotoxin can be used as a challenge model to study inflammatory processes within the airways. Substantial amounts of endotoxin (15 – 50 μg) were used in the past to elicit a neutrophilic airway inflammation by conventional inhalation. In contrast, controlled inhalation can largely increase deposition. Because regulatory requirements in many countries request GMP-grade endotoxin which is of limited availability, controlled inhalation with low doses of endotoxin might allow to overcome this shortage. Therefore, the aim of this study was to investigate whether a lowdose endotoxin inhalation results in a sufficient neutrophilic airway inflammation.