Approach to corticosteroid-dependent and corticosteroid-refractory Crohn's disease.

Corticosteroids are considered a drug of choice for the treatment of patients with moderately to severely active Crohn's disease (CD), an inflammatory bowel disease characterized by chronic recurrent flares of disease activity. However, among patients receiving corticosteroid therapy for induction of remission, 20% have corticosteroid-refractory disease and 36% of those with an initial response develop corticosteroid dependency within 1 year. Chronic corticosteroid exposure in patients who are corticosteroid dependent increases the risk for serious drug-related adverse effects. Withdrawal or reduction of corticosteroid therapy without exacerbation of symptoms is therefore recognized as an important goal of treatment. Therapies that have been shown to facilitate "steroid sparing' include the immunomodulators azathioprine/6-mercaptopurine and methotrexate and the antitumor necrosis factor-alpha monoclonal antibody infliximab. In corticosteroid-dependent patients, budesonide may be substituted for conventional corticosteroid therapy without loss of response and with less risk for toxicity, but its long-term efficacy requires further evaluation. A preliminary controlled study suggests that the investigational anti-TNF monoclonal antibody CDP-571 may also be clinically beneficial as a corticosteroid-sparing agent. This review summarizes the clinical evidence that supports consideration of these agents as alternatives in patients with CD who are dependent on, refractory to, or intolerant of conventional corticosteroid therapy.