Preventives/remedies for inflammatory airway diseases

A preventive and/or therapeutic agent for inflammatory respiratory tract diseases containing, as an active ingredient, a steroid derivative represented by the following formula (1): (wherein R represents a hydrogen atom, a halogen atom, a hydroxy group, or -OCOR1 (wherein R1 represents a linear or branched alkyl group which may be substituted by a halogen atom or a cycloalkyl group; a cycloalkyl group; or an aryl group)). These compounds can continuously suppress respiratory tract inflammation and respiratory tract hyperreaction and show a high site selectivity and little systemic effect when administered directly to the respiratory tract. By virtue of these characteristics, these compounds are remarkably useful in clinical medicine as highly safe preventive and/or therapeutic agents for inflammatory respiratory tract diseases which can be administered for a long period of time.