In a single-institution phase II study reported in the Journal of Clinical Oncology, Rashidi et al found that fecal microbiota transplantation (FMT) did not reduce the risk of infection in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) or patients with acute myeloid leukemia (AML) receiving induction therapy. However, FMT improved postantibiotic recovery of gut microbiota diversity.
The double-blind study involved two parallel cohorts of patients treated at the University of Minnesota: an allo-HCT cohort of 74 patients randomly assigned 2:1 to receive FMT capsules (n = 49) or placebo (n = 25); and an AML cohort of 26 patients randomly assigned 2:1 to receive FMT capsules (n = 16) or placebo (n = 8). Third-party FMT was conducted with product from four different donors and each patient receiving material from only one donor. Treatments were administered upon neutrophil recovery and were given after each course of prophylactic oral antibiotics; up to three treatments were given within 3 months. The primary endpoint was 4-month all-cause infection rate.
In the allo-HCT cohort, 4-month infection density was 0.74 events per 100 patient-days in the FMT group vs 0.91 events per 100 patient-days in the placebo group (infection rate ratio = 0.83, 95% confidence interval [CI] = 0.48–1.42, P = .49). In the AML cohort, 4-month infection density was 0.93 events per 100 patient-days in the FMT group vs 1.25 events per 100 patient-days in the placebo group (infection rate ratio = 0.74, 95% CI = 0.32–1.71, P = .48).
Donor bacterial sequences accounted for 25% to 30% of fecal microbiota after FMT. FMT improved postantibiotic recovery of microbiota diversity; restored several depleted obligate anaerobic commensals; and reduced the abundance of expanded genera Enterococcus, Streptococcus, Veillonella, and Dialister.
The investigators concluded, “In allogeneic HCT recipients and patients with AML, third-party FMT was safe and ameliorated intestinal dysbiosis, but did not decrease infections. Novel findings from this trial will inform future development of FMT trials.”
Armin Rashidi, MD, PhD, of Fred Hutchinson Cancer Center, Seattle, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by National Cancer Institute grants and others. For full disclosures of the study authors, visit ascopubs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.