A live biotherapeutic product for adult allogeneic hematopoietic cell transplantation recipients: a partially randomized, placebo-controlled phase 1b trial

Nature Medicine, Published online: 03 November 2026; doi:10.1038/s41591-026-04686-y In a phase 1b study that included an open-label and randomized-controlled cohorts of allogeneic hematopoietic cell transplantation recipients, treatment with the investigational, cultivated, multi-strain bacterial oral live biotherapeutic product, SER-155, was found to have a similar safety profile to placebo and resulted in fewer bloodstream infections, indicating further clinical investigation of this therape