Ciclesonide (CIC) is a prodrug form of the glucocorticoid receptor agonist desisobutyryl-CIC (des-CIC). CIC binds to the glucocorticoid receptor with a Ki value of 37 nM. It is selective for the glucocorticoid receptor over the estrogen, progesterone, and testosterone receptors. CIC inhibits eosinophil influx into the lung (ED50 = 0.49 mg/kg) and reduces sephadex-induced lung edema (ED50 = 0.72 mg/kg) in a rat model of ovalbumin-sensitized and -challenged airway inflammation. Formulations containing CIC have been used in the maintenance treatment of asthma and in the treatment of allergic rhinitis.