What's New and What's Next in Fecal Microbiota Transplantation?

Abstract

Fecal microbiota transplantation (FMT) has evolved from a niche therapy to a cornerstone in the treatment of recurrent Clostridioides difficile infection (rCDI). Initially introduced in the 1950s, its relevance has surged with the emergence of virulent and antibiotic-resistant C. difficile strains. In recent years, the FDA approved two standardized microbiota-based therapeutics-Rebyota™ (fecal microbiota, live-jslm) and Vowst™ (fecal microbiota spores, live-brpk)-for rCDI prevention. Multiple pivotal trials support the efficacy and safety of both traditional FMT and the FDA-approved prescription FMTs, with sustained response rates surpassing 80% in select populations. In parallel, live biotherapeutic products (LBPs)-donor independent, well-defined microbial consortia produced in laboratory setting are under development. Examples include VE303 and NTCD-M3, a single non-toxigenic C. difficile strain (M3). Beyond the FDA approved therapeutics, conventional FMT is gaining traction as a potential treatment for severe or fulminant CDI, especially in patients not responding to antibiotics and ineligible for surgery. Investigational indications include decolonizing multidrug-resistant organisms and treatment of noninfectious conditions such as inflammatory bowel disease, irritable bowel syndrome, liver disease, and metabolic syndrome. Given the differing pathophysiology of these conditions, a tailored approach supported by rigorous clinical trials is essential. Although there is a growing shift, particularly in the United States, toward the use of FDA-approved FMTs, global practices remain heterogeneous, with conventional FMT still widely employed. Meanwhile, regulatory pathways and clinical guidelines for microbiota-derived biologics and live biotherapeutic products continue to evolve. In this manuscript, we provide an update on the emerging use of FDA-approved prescription microbiota-derived therapeutics for the prevention of rCDI, review data on investigational agents including both donor dependent and donor independent microbial products, and summarize current evidence on the use of conventional FMT for indications beyond prevention of rCDI.