[en] Inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis are frequent illnesses in western countries. They have a dramatic impact on the health-related quality of life. The new biological treatments developed for these diseases are potentially very effective, but are also expensive and may have significant side effects. In the present paper, the authors describe new biological therapies used during the past 10 years at the CHU. More than 20 therapeutic protocols were implemented. These protocols have given the patients the opportunity to gain very rapid access to new efficient therapies, to benefit from promising techniques for the evaluation of their pathology and to be submitted to a close follow-up that frequently called their treatment into question in the light of the most innovative options.