Fecal Microbiota Transplantation in Crohn's Disease as Relay After Anti-TNF Withdrawal

Crohn's disease (CD) is a chronic inflammatory bowel disease. CD pathogenesis remains poorly understood but involves an inappropriate immune response toward an unbalanced gut microbiota in predisposed hosts. The purpose of this study is to evaluate de clinical efficacy of the fecal microbiota transplantation (FMT) as a maintenance treatment following anti-TNF agent withdrawal in CD's patient.

Crohn's disease (CD) is a chronic inflammatory bowel disease affecting approximately 120000 patients in France, mostly at young age, and altering their quality of life. Immunosuppressive treatments in CD are expensive and associated with potentially severe complications. Alternative treatment strategies are thus required. This is particularly the case for CD patients in remission under anti-TNF agents for which no specific recommendation are available. CD pathogenesis remains poorly understood but involves an inappropriate immune response toward an unbalanced gut microbiota in predisposed hosts. Fecal microbiota transplantation (FMT) is currently recommended for treating recurrent Clostridium difficile infection. Although the pathogenesis involved in CD differs, FMT is a potential therapeutic strategy that could restore the appropriate host-microbiota crosstalk by transferring a healthy microbiota in a CD patient. However, as the gut microbiota is dramatically altered by intestinal inflammation, transferring a massive amount of microbes in an inflamed gut with epithelial barrier disruption might be a suboptimal strategy and could even have detrimental effects by allowing bacterial translocation. Results of randomized controlled trial (RCT) in CD are lacking to date. We performed a pilot RCT (NCT02097797), evaluating the impact of a single FMT in 18 CD patients who achieved remission by corticosteroid treatment. A higher rate of steroid free clinical remission was observed in the FMT arm at 24 weeks (57.1% vs 33.3% in FMT and control arm respectively). CD Endoscopic Index of Severity was also improved at 6 weeks in FMT (median 8.5 vs 3.5 p=0.03) but not in sham group (median 2.4 vs 2.7 p=0.8). Moreover, the only 2 patients who early relapsed in the FMT group were those who did not show any engraftment of donor microbiota at week 6. These promising data, currently submitted for publication, suggest that using FMT as a maintenance treatment in CD can be effective. However, these promising findings need to be confirmed by a Phase III RCT.