Designing corticosteroid drugs for pulmonary selectivity.

Inhaled corticosteroids have become indispensable for the treatment of asthma and chronic obstructive pulmonary disease. Significant progress has been made toward minimizing side effects through the use of increasingly selective molecules, and through a variety of lung targeting strategies. Many of these developments have occurred in advance of a greatly improved understanding of corticosteroid biology at the molecular and pharmacologic level, and it has become clear that additional opportunities exist for the further enhancement of therapeutic index. This article discusses significant recent developments in the chemistry, biology, and pharmacology of corticosteroids, and considers the implications for the future use of inhaled corticosteroids.