Effect of formoterol with or without budesonide in repeated low-dose allergen challenge

The use of combination therapy In mild asthma Is debated. The current authors evaluated the effects of formoterol alone and a formoterol/budesonide combination Inhaler on asthma deterioration Induced by repeated low-dose allergen exposure. In total, 15 subjects with intermittent allergic asthma Inhaled low doses of allergen on seven consecutive weekdays In a three-period, crossover, double-blind, double-dummy comparison between formoterol 4.5 mu g Turbuhaler (TM), budesonide 160 mu g/formoterol 4.5 mu g Turbuhaler (TM) and placebo, each taken as two puffs 30 min after allergen dosing. The outcome variables were: provocative dose of methacholine causing a 20% fall In forced expiratory volume In one second (PD20), exhaled nitric oxide fraction (FeNO), sputum eosinophils and prostaglandin D(2), and diary card recordings of symptoms (on a scale of 0-10), short-acting beta(2)-agonist use and evening forced expiratory volume In one second (FEV1). With placebo treatment, allergen exposure caused significant Increases In airway hyperresponsiveness (geometric mean (coefficient of variation) PD20: 397 (98) mu g before versus 168 (82) mu g after), FeNO (mean +/-SD 46+/-31 ppb before versus 73+/-46 ppb after) and asthma symptom score (mean +/-SD 0.39+/-0.55 before versus 0.68+/-0.67 after). Budesonide/formoterol abolished these changes and significantly Improved baseline FEV1. Formoterol alone, while providing symptom relief, was no better than placebo In protecting against the allergen-induced Increase In airway Inflammation. Signs of deteriorating asthma, provoked by low-dose allergen, are prevented by short-term use of budesonide/formoterol but not by temporary use of formoterol alone.