Oral Vancomycin Followed by Fecal Transplantation Versus Tapering Oral Vancomycin Treatment for Recurrent Clostridium difficile Infection: An Open-Label, Randomized Controlled Trial

Background. Fecal transplantation (FT) is a promising treatment for recurrent Clostridium difficile infection (CDI), but its true effectiveness remains unknown. We compared 14 days of oral vancomycin followed by a single FT by enema with oral vancomycin taper (standard of care) in adult patients experiencing acute recurrence of CDI. Methods. In a phase 2/3, single-center, open-label trial, participants from Ontario, Canada, experiencing recurrence of CDI were randomly assigned in a 1: 1 ratio to 14 days of oral vancomycin treatment followed by a single 500-mL FT by enema, or a 6-week taper of oral vancomycin. Patients with significant immunocompromise, history of fulminant CDI, or irreversible bleeding disorders were excluded. The primary endpoint was CDI recurrence within 120 days. Microbiota analysis was performed on fecal filtrate from donors and stool samples from FT recipients, as available. Results. The study was terminated at the interim analysis after randomizing 30 patients. Nine of 16 (56.2%) patients who received FT and 5 of 12 (41.7%) in the vancomycin taper group experienced recurrence of CDI, corresponding with symptom resolution in 43.8% and 58.3%, respectively. Fecal microbiota analysis of 3 successful FT recipients demonstrated increased diversity. A futility analysis did not support continuing the study. Adverse events were similar in both groups and uncommon. Conclusions. In patients experiencing an acute episode of recurrent CDI, a single FT by enema was not significantly different from oral vancomycin taper in reducing recurrent CDI. Further research is needed to explore optimal donor selection, FT preparation, route, timing, and number of administrations.