Seres has finalized the protocol for the Phase 2 study of SER-155 in patients undergoing allogeneic hematopoietic stem cell transplant (allo-HSCT) with the FDA and has advanced key study startup activities and will pause further investment, while efforts to seek funding for the study remain ongoing Company's runway extension actions, including reducing the workforce by approximately 30%, are expected to extend its cash runway through Q3 2026 Seres will focus on advancing development of its early-stage live biotherapeutic programs in Inflammatory and immune diseases and supporting the read-out of clinical results from the fully enrolled Investigator-sponsored SER-155 study in immune checkpoint related enterocolitis (irEC), a frequent and severe adverse events in recipients of ICI therapy, expected in early Q2 2026 CAMBRIDGE, Mass., Feb. 12, 2026 (GLOBE NEWSWIRE) -- Seres Therapeutics, Inc. (Nasdaq: MCRB), a leading live biotherapeutics company, today announced that, following advancement of key startup activities for the SER-155 Phase 2 study in allo-HSCT, including the submission of a final protocol to the FDA, study site evaluation and qualification with its CRO, and manufacturing of Phase 2 study drug substance, Seres is pausing additional investment in that program and will shift its operational focus to high-value earlier-stage pipeline programs while continuing to seek funding for the SER-155 Phase 2 study.
