Abstract
Background: The combination of budesonide/formoterol (BUD/FORM) is an effective and well-tolerated treatment for asthma. Most clinical studies have focused on improvements in lung function and have used exacerbation rate as a marker of inflammation control. We evaluated the effects of BUD/FORM, BUD alone and FORM alone on airway hyperresponsiveness (AHR) and inflammation in a model using an allergic mouse.
Methods: BALB/c mice were randomised into 10 groups (10 mice/group) and intraperitoneally sensitised with ovalbumin (OVA), aluminium hydroxide or saline on Days 0 and 7, then challenged with OVA (10 mg/mL) or saline aerosol for 60 minutes on Days 14 and 15. Two hours before OVA challenge, animals were intratracheally treated with vehicle, BUD/FORM (30/0.86, 100/2.86, 300/8.6 μg/mL/kg) or equivalent concentrations of BUD alone or FORM alone.
Results: BUD/FORM in combination (100/2.86 μg/mL/kg) significantly inhibited bronchoalveolar lavage eosinophilia, lung oedema (measured by increased lung weight) and AHR (measured by methacholine-induced excised lung gas volume). These effects were significantly greater than those of equivalent doses of BUD or FORM alone. BUD/FORM (300/8.6 μg/mL/kg) was more effective at inhibiting AHR and cell inflammation or infiltration than FORM alone, but not BUD alone.
Conclusion: BUD/FORM in combination can, depending on the dose, show better therapeutic effects on AHR and inflammation than either monocomponent alone in an OVA-challenged mouse model.