Onset of action of intranasal budesonide (Rhinocort Aqua) in seasonal allergic rhinitis studied in a controlled exposure model

Background: Intranasal budesonide aqueous nasal spray (BANS) is recognized as an efficacious treatment for seasonal allergic rhinitis (SAR), but the t ime to onset of action is not known. Objective: The primary objective was to evaluate the time at which the onse t of action of BANS in the symptomatic relief of seasonal allergic rhinitis becomes evident within 12 hours after a single dose in a controlled ragwee d pollen exposure setting. Methods: The study was of a double-blind, randomized, parallel-group design , testing BANS (64 mu g and 256 mu g) and placebo on ragweed-sensitive subj ects with symptoms for at feast 1 year by using a controlled pollen challen ge system (Environmental Exposure Unit). The efficacy variables a ere the c ombined nasal score (the sum of blocked nose, runny nose, and sneezing-itch y nose), individual nasal symptoms, overall evaluation of treatment efficac y reported by participants on diaries, and peak nasal inspiratory flow (PNI F), Results: A total of 217 participants were treated with BANS or placebo. At 7 to 12 hours, BANS was better than placebo in reducing combined nasal and blocked nose symptoms. For PNIF, the time to onset of action was shortest f or 256 mu g of BANS relative to placebo (3 hours, P = .003). BANS 64 mu g w as better than placebo in reducing the individual scores of blocked nose, r unny nose, and sneezing itchy nose from 3 to 5 hours after administration. Treatment efficacy was higher for those receiving BANS compared with placeb o starting at 5 hours. All treatments were well tolerated, and no specific adverse events occurred. Conclusions: The onset of action of Intranasal BANS was 7 hours according t o combined nasal and blocked nose symptom scores. Evidence of earlier respo nse was observed at 3 hours for runny nose and PNIF.