Safety and efficacy of fecal microbial transplantation for the prevention and treatment of acute graft-versus-host disease: a meta-analysis.

Objective: In recent years, fecal microbiota transplantation (FMT) has been increasingly investigated for the prevention and treatment of acute graft-versus-host disease (aGVHD). Nevertheless, its clinical efficacy remains uncertain. Therefore, this study aims to systematically evaluate the clinical efficacy of FMT in preventing and treating aGVHD. Methods: We systematically searched Cochrane Library, PubMed, Embase, and Web of Science from inception to October 2025 for studies comparing FMT with conventional regimens (corticosteroids and/or immunosuppressants) for aGVHD prevention and treatment. All statistical analyses were performed using RevMan 5.4.1 and Stata 16. Results: Six studies involving 262 patients were included. Among them, 85 patients received FMT for aGVHD prevention, 65 received conventional prophylaxis, 68 received FMT for Gastrointestinal aGVHD (GI-aGVHD) treatment, and 44 received conventional treatment for GI-aGVHD. Meta-analysis showed no significant difference in the incidence of aGVHD between the FMT and conventional groups [odds ratio (OR) = 1.30, 95% confidence interval (CI) = 0.10-16.72, Conclusion: FMT showed favorable effects in improving clinical symptoms of GI-aGVHD and increasing the abundance of beneficial gut bacteria, and no increased risk of bloodstream infection was observed. These findings suggest that, for patients with established GI-aGVHD who may respond poorly to conventional regimens, FMT can serve as an effective adjunctive or salvage treatment. However, no significant advantage was observed for FMT in preventing aGVHD.