Intranasal mometasone furoate reduces late-phase inflammation after allergen challenge

Background: Allergen specific nasal challenge (ASNC) is an optimal model to study the pathophysiologic mechanisms sustaining allergic inflammation, particularly the adhesion molecules promoting cellular infiltration of nasal mucosa. Topical corticosteroids have been accepted as a highly effective anti-inflammatory therapy for allergic rhinitis. Objective: The aim of this double-blind, randomized, placebo-controlled study was the evaluation of inflammatory events, during the late-phase, after a 2-week treatment with nasal mometasone furoate (MF), 200 mug daily, or placebo, using the model of ASNC. Methods: A total of 42 patients with allergic rhinitis underwent nasal challenge before and after treatment. The following parameters were evaluated at baseline, and 6 hours (late-phase) after ASNC: 1) nasal symptoms (rhinorrhea, itching, sneezing, obstruction); 2) inflammatory cells (eosinophils and neutrophils); 3) eosinophil cationic protein (ECP) and tumor necrosis factor-alpha (TNF-alpha) in nasal lavage; and 4) intercellular adhesion molecule-1 expression on nasal epithelial cells. Results: MF nasal spray was associated with late-phase reductions of: 1) clinical symptoms (P < 0.03); 2) eosinophil (P < 0.004) and neutrophil (P < 0.003) infiltration; 3) ECP (P < 0.001) and TNF-alpha (P < 0.05); and 4) intercellular adhesion molecule-1 expression on nasal epithelial cells (P < 0.001). Conclusions: The present results demonstrate that MF has a significant effect on late-phase events, reducing the cellular influx and activation.