Anti-tumor necrosis factor nonresponders in Crohn's disease: therapeutic strategies.

Anti-TNF antibodies have revolutionized the treatment of Crohn's disease. In pivotal trials, however, the frequencies of primary and secondary nonresponders appeared rather high with, by the end of 1 year of scheduled treatment, only one fifth of the patients initially treated still in sustained remission. Other studies and monocentric experiences have indicated that these seemingly disappointing results were partly due to suboptimal selection of the patients and absence of treatment optimization. Optimal selection of the patient includes proving active intestinal lesions and systemic inflammation as well as excluding stricturing or infectious complications. Treatment optimization includes potential immunosuppressive co-treatment and dose or administration interval adjustment of the anti-TNF. When a failure is confirmed with an anti-TNF despite such optimization, second- or third-line anti-TNFs have proved useful. Beyond that, a transient steroid course and surgical procedures still represent rescue option, waiting for new promising biologics in development.