Seres Therapeutics, Inc. is a pioneering microbiome therapeutics firm dedicated to engineering bacterial consortia that modulate host cells and tissues to combat various diseases. Their flagship therapeutic, SER-109, an oral microbiome treatment, has successfully concluded Phase III clinical trials for the management of Clostridioides difficile infection (CDI). The company's pipeline further encompasses SER-155, a synthetically cultured bacterial formulation currently undergoing Phase Ib evaluation. This candidate aims to mitigate the risk of gastrointestinal and bloodstream infections, alongside graft-versus-host disease, in vulnerable patients undergoing allogeneic hematopoietic stem cell or solid organ transplantation. Additionally, Seres Therapeutics is advancing SER-287 and SER-301, both in Phase Ib for ulcerative colitis, as well as SER-401, which targets metastatic melanoma, and SER-262, also directed at Clostridioides difficile infection. Seres maintains strategic alliances through licensing and collaboration agreements with entities such as Nestec Ltd. and Memorial Sloan Kettering Cancer Center. Established in 2010, the company previously operated as Seres Health, Inc. before adopting its current name in May 2015, and it maintains its principal offices in Cambridge, Massachusetts.