Oral corticosteroid-dependent asthma: current knowledge and future needs

Purpose of review To discuss the current use of oral corticosteroids (OCS) as a chronic treatment in patients with severe asthma and as a rescue treatment for patients presenting with acute exacerbations. Recent findings Airways disease is responsible for the bulk of OCS use in the community and considerable OCS-associated morbidity. I speculate that the key mechanism leading to a beneficial effect in these situations is depletion of circulating eosinophils resulting in a reduced response to potentially inhaled corticosteroid unresponsive recruitment signals to the airway mucosa. This effect is shared by anti-IL-5 biological agents, which have emerged as highly effective OCS-sparing agents. Mitigation of the adverse effects of OCS might also result from a better appreciation of features associated with a response to OCS and targeted, biomarker-directed use. Summary Longer term, there are real prospects that chronic and acute OCS use in asthma will be replaced by biological agents targeting eosinophilic airway inflammation more specifically and safely.