Introduction: The gut microbiome is implicated in Clostridioides difficile infection (CDI) and recurrent CDI (rCDI).
Areas covered: This review covers the mechanisms by which microbiome therapeutics treat rCDI, their efficacy and safety, and clinical trial design considerations for future research.
Expert opinion: Altering the chemical environment of the gut and reconstituting colonization resistance is a promising strategy for preventing and treating rCDI. Fecal microbiota transplant (FMT) is safe and effective for the treatment of rCDI. However, limitations of FMT have prompted investigation into alternative microbiome therapeutics. These alternative microbiome therapies require further evaluation, and adaptive trial designs should be strongly considered to more rapidly discern variables including the need for bowel preparation, timing and selection of pre-treatment antibiotics, and dose and duration of microbiome therapeutics. A broad range of adverse events must be prospectively evaluated in these controlled trials, as microbiome therapeutics have the potential for numerous effects. Future studies will lead to a greater understanding of the mechanisms by which microbiome therapies can break the cycle of rCDI, which should ultimately yield a personalized approach to rCDI treatment that restores an individual's specific deficit(s) in colonization resistance to C. difficile.
Keywords: C. difficile; fecal microbiota transplant; microbiome; microbiome therapeutics.