Seres Therapeutics, Inc. is a clinical-stage company focused on improving patient outcomes in medically vulnerable populations through novel live biotherapeutics. It is developing SER-155, which has shown a significant reduction in bloodstream infections and related complications (as compared to placebo) in a Phase 1b clinical study in patients undergoing allo-HSCT and Fast Track designation to reduce the risk of infection and graft-versus-host disease in adults undergoing allo-HSCT. SER-155 and the Company’s other pipeline programs are designed to target multiple disease-relevant pathways. In addition to allo-HSCT, it intends to evaluate SER-155 and other cultivated live biotherapeutic candidates in other medically patient populations, including autologous-HSCT patients, cancer patients with neutropenia, CAR-T recipients, individuals with chronic liver disease, solid organ transplant recipients, as well as patients in the intensive care unit and long-term acute care facilities.