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Seres Therapeutics Presents New Preclinical Data Supporting the Development of Microbiome Therapeutics for Immuno-Oncology at the 2018 American Association for Cancer Research Annual Meeting

Apr 17, 2018 at 12:00 PM EDT

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Apr. 17, 2018-- Seres Therapeutics, Inc. (NASDAQ:MCRB) today announced that new preclinical data supporting the development of microbiome therapeutics for immuno-oncology (leveraging gut microbiota to impact tumor immunotherapy)1 will be presented today by Sceneay et al in the late breaking poster session at the 2018 American Association for Cancer Research Annual Meeting (AACR) in Chicago. The data presented provide new insights on the potential mechanism by which Seres’ microbiome therapies could improve the outcomes of cancer patients treated with immune checkpoint inhibitors.

“The data presented at AACR provide important new models and mechanistic insights that inform our planned development efforts to evaluate the ability of microbiome therapy to augment immune checkpoint inhibitors,” said David Cook, Ph.D., Chief Scientific Officer and Executive Vice President of Research at Seres. “The insights described in this presentation will guide the continued development of SER-401, which we expect to enter clinical development later this year. Our objective is to use our microbiome therapeutic approach to improve the efficacy of immunotherapy in patients with life-threatening cancers.”

Seres presented results from preclinical studies designed to evaluate the impact of various consortia of bacterial species on the anti-tumor immune response in murine models following treatment with an anti-PD-1 checkpoint inhibitor. Results demonstrated that both germ-free mice lacking a microbiome and antibiotics-treated mice with a dysbiotic microbiome, failed to mount an effective anti-tumor response following treatment with an anti-PD-1 checkpoint inhibitor. The response to anti-PD-1 was restored in germ-free as well as antibiotics-treated mice by introducing a diverse microbiome, and was driven by increased entry of tumor-infiltrating lymphocytes into the tumor; specifically, CD8+ T effector cells. Current pre-clinical efforts are focused on optimizing specific microbiome compositions based on functional and phylogenetic information to inform the development of therapeutic candidates.

Seres is developing SER-401, a preclinical stage oral microbiome therapy comprising a consortium of live bacteria to improve the efficacy and safety of immunotherapy. Through a collaboration with The University of Texas MD Anderson Cancer Center and the Parker Institute for Cancer Immunotherapy, Seres plans to initiate a clinical study in patients with advanced metastatic melanoma later this year. In a 2017 study published in Science, the MD Anderson research team, led by Dr. Jennifer Wargo, described a microbiome signature associated with response to checkpoint inhibitor therapy. A planned clinical trial will evaluate the impact of an anti-PD-1 checkpoint inhibitor with adjunctive microbiome therapy on patient outcomes.

About Seres Therapeutics

Seres Therapeutics, Inc., is a leading microbiome therapeutics platform company developing a novel class of biological drugs that are designed to treat disease by restoring the function of a dysbiotic microbiome, where the natural state of bacterial diversity and function is imbalanced. Seres’ lead program, SER-109, has obtained Breakthrough Therapy and Orphan Drug designations from the U.S. Food and Drug Administration and is in Phase 3 development for multiply recurrent C. difficile infection. Seres’ clinical candidate SER-287 has successfully completed a Phase 1b study in patients with mild-to-moderate Ulcerative Colitis. Seres is also developing SER-262, the first ever synthetic microbiome therapeutic candidate, in a Phase 1b study in patients with primary C. difficile infection. For more information, please visit Follow us on Twitter @SeresTx.


1. Sceneay, Jaclyn et. al., Leveraging gut microbiota to impact tumor immunotherapy. Poster. American Association for Cancer Research Annual Meeting 2018.

Source: Seres Therapeutics, Inc.

Seres Therapeutics
Carlo Tanzi, Ph.D., 617-203-3467
Vice President, Investor Relations and Corporate Communications

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