Schema for the clinical trial and longitudinal biospecimen collection.
B acute lymphoblastic lymphoma, GVHD
GVHD
Study participants received 20 g RPS orally daily for the first 3 days followed by twice daily, from day −7 through to day 100 after allogeneic HCT. Stool and blood specimens were collected from the study participants at baseline before conditioning (day −7), nadir (approximately days 5–7), engraftment (approximately day 14) and day 100. Stool samples were collected weekly after allogeneic HCT when possible. Samples were compared to samples obtained from past historical controls not receiving the dietary intervention at the same time points relative to allogeneic HCT. After the feasibility phase, an additional 50 individuals will be enrolled on phase 2 of the trial to receive RPS on the same schedule noted above and ten individuals will be enrolled to receive isocaloric, nonresistant starch placebo, who will serve as contemporaneous controls (5:1 randomization). Stool and blood specimens will be collected on the same schedule as the feasibility phase.Patients with allogeneic HCT often suffer from treatment-related GI distress and GVHD, thus making dietary interventions difficultParticipants’ clinical characteristicsThree patients with myelodysplastic syndrome;two patients with acute myeloid leukemia;four patients with B acute lymphoblastic lymphoma; one patient with follicular lymphomaFluBu4, fludarabine and busulfan myeloablative conditioning; CyTBI, cyclophosphamide and total body irradiation myeloablative conditioning.Feasibility met the preset goal of 70% or greater adherence to scheduled dosages in 60% or more patients; eight out of ten patients (80%) received 70% or more of the scheduled doses. The median percentage dose taken by participants was 84% (Table RPS administration and longitudinal specimen collection in ten patients with allogeneic HCTTaken together these results suggest that the use of RPS as a dietary intervention during allogeneic HCT is feasible, tolerable and safe.