RESUMO
BACKGROUND: Mometasone furoate is a potent glucocorticoid that can markedly inhibit proinflammatory Th2 cytokines in vitro. An aqueous nasal spray formulation has been shown to be clinically active in reducing the symptoms of perennial and seasonal allergic rhinitis. OBJECTIVE: To determine whether pretreatment with mometasone furoate 200 microg once daily decreases specific indices of early and late phase nasal inflammation compared with placebo. METHODS: A randomized, double-blind, placebo-controlled crossover study was conducted using nasal provocation with ragweed antigen in 21 patients with ragweed-induced allergic rhinitis out of the ragweed season; the treatment period was 2 weeks. Symptom scores, rhinoprobe cytology, and nasal lavage fluid were collected during early and late phase periods for nasal cytokines (interleukin, 1, 4, 5, 6, and 8) and leukotriene B4 determinations using ELISA and RIA. RESULTS: Mean nasal symptom scores and sneezing frequency were consistently lower with mometasone furoate compared with placebo. Treatment was associated with a statistically significant early phase (30-minute time point) reduction in nasal lavage histamine levels compared with placebo (14.3 versus 20.2 ng/mL, P = .02). Within-treatment comparisons suggested that mometasone furoate reduced the antigen-induced late-phase response for IL-6, IL-8, and eosinophils compared with pretreatment. There were similar, but smaller, changes seen in the placebo group for these measurements. There were no statistically significant changes following antigen challenge in IL-1, IL-4, IL-5, LTB4, or in other nasal cytology parameters. CONCLUSION: These results suggest that the clinical activity of mometasone furoate nasal spray in seasonal allergic rhinitis is likely due, in part, to a reduction in the levels of histamine in nasal secretions related to the early phase response, and reductions in IL-6, IL-8, and eosinophils during the late phase response.