Bioequivalence study comparing a generic formulation of budesonide nasal spray with the innovator budesonide nasal spray with a 7 day run-in period, conducted in healthy participants with a history of seasonal allergic rhinitis.

Sequential, placebo controlled, parallel group study design whereby each participant receives an initial 7-day placebo run-in period to establish a baseline and to identify placebo responders. Participants who respond to the placebo will be eliminated from the study. Dosing will take place daily throughout the 7-day placebo run-in period and the 14-day double-blind randomised treatment period. The intervention for this trial is the test formulation of budesonide (2 x 64 mcg of budesonide per nostril daily) The placebo treatment is sodium chloride in water (Saline) No water or food is allowed for 1 hour prior to dosing until 1 hour after dosing. Participants are required to attend dosing at Zenith Technology during the 7 day placebo period for approximately 30 minutes each morning. Participants accepted into the treatment study will then be required to attend dosing at Zenith Technology for a further 14 days for approximately 30 minutes each morning. all dosing is monitored by a staff member to ensure dosing has been completed correctly. Pre and post study laboratory tests will be completed to assess the health of participants along with HIV, Hepatitis and drugs of abuse testing. A skin prick test will be carried out to determine if the participant has an allergy to mixed grass pollen as well as a nasal allergen provocation test to establish the individual threshold dose to induce a response (sneezing).