Seres Therapeutics, Inc. MCRB

What this company does

We are a clinical-stage company focused on improving patient outcomes in medically vulnerable populations through discovery and development of novel live biotherapeutic product, or LBP, candidates. We led the successful development and approval of VOWST, the first FDA-approved orally administered microbiome biotherapeutic and a Breakthrough Therapy designated drug, which was sold to Société des Produits Nestlé S.A., or SPN, and with certain of its affiliates, collectively, Nestlé Health Science, in September 2024. Our pipeline consists of SER-155, SER-603, and SER-147, as well as other potential candidates in earlier development. Our LBP candidates are consortia of bacteria designed to optimize specific, targeted pharmacological properties, and are formulated for oral delivery. SER-155, our most advanced LBP candidate, is an investigational, oral, live biotherapeutic designed to decolonize GI pathogens, improve GI epithelial barrier integrity, and induce immune homeostasis to prevent bacterial BSIs, including those that can harbor antimicrobial resistance, as well as other pathogen-associated negative clinical outcomes in patients undergoing allogeneic hematopoietic stem cell transplantation, or allo-HSCT. We are evaluating SER-155 in immune checkpoint-related enterocolitis, or irEC, and we are developing SER-603, broadly in inflammatory bowel disease, or IBD, including ulcerative colitis, or UC, and Crohn's disease.

Written from the business description in Seres Therapeutics, Inc.'s annual report to the U.S. Securities and Exchange Commission, filed 12 March 2026. Every sentence was checked against that document before publication.