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Seres Therapeutics to Present New Data Supporting SER-109 Clinical Activity at IDWeek 2018

Oct 3, 2018 at 7:00 AM EDT

Findings support SER-109 Phase 3 program as a potential new treatment option for C. difficile infection

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Oct. 3, 2018-- Seres Therapeutics, Inc. (Nasdaq:MCRB) today announced it will present new data for SER-109, a microbiome candidate in Phase 3 development, at the IDWeek 2018 conference being held from October 3-7 in San Francisco, CA. The findings, highlighted in two presentations, provide support for SER-109 as a potential new treatment option for individuals suffering from recurrent C. difficile infection. The company will also host a symposium on the development on novel microbiome therapeutics for C. difficile infection.

“These additional SER-109 data provide valuable information about the potential mechanism of action of microbiome therapeutics, an emerging new field of medicine. Our results provide additional evidence supporting the continued development of SER-109 in patients with recurrent C. difficile infection. In addition, these new data suggest that SER-109 may have important broader public health benefits by reducing the spread of antibiotic resistance,” said Matthew Henn, Ph.D., Executive Vice President, Microbiome Research and Development at Seres Therapeutics.

C. difficile infection is often treated with extended antibiotic regimens, resulting in damage to the natural gastrointestinal microbiome and proliferation of antibiotic resistant bacteria1. Data from Ford et al., based on analysis of SER-109 Phase 2 study samples, demonstrate that SER-109 administration increases microbiome diversity and that outgrowth of SER-109 bacteria is associated with a reduction in the abundance of antibiotic resistance genes in subjects’ gastrointestinal tract. These new results suggest that microbiome therapeutics have the potential to address the spread of antibiotic resistance, a major public health concern.

In a separate presentation, Henn et al. show that SER-109 administration and subsequent bacterial outgrowth leads to changes in the metabolic products created by the gastrointestinal microbiota, including higher concentrations of secondary bile acids. Secondary bile acids are generated by bacteria residing in the gut, and published studies suggest that these molecules inhibit the growth of C. difficile2. The findings provide important insights into the potential mechanism of action of SER-109 for C. difficile infection.

Oral Presentation Details:

Title: Treatment of Recurrent Clostridium difficile Infection with SER-109 Reduces Gastrointestinal Carriage of Antimicrobial Resistance Genes
Author: Ford C. et al.
Session: Novel Therapies for Superbugs
Date: Friday, 2:00 - 3:15 p.m.

Poster Presentation Details:

Title: Treatment of Recurrent Clostridium difficile Infection with SER-109 Increases the Concentration of Secondary Bile Acids in a Dose Dependent Manner
Author: Henn M. et al.
Session: Microbiome and Beyond
Date: Thursday, 12:30 - 1:45 p.m.

Title: An Ecological Approach to the Treatment of Recurrent Clostridium difficile Infection: Picking Up Where Antibiotics Leave Off
Speaker: Stuart Cohen, MD, Chief of Infectious Diseases, Professor of Medicine, University of California, Davis
Date: October 4th and 5th, 12:15 -1:00 pm
Location: Learning Lounge 2

About Seres Therapeutics

Seres Therapeutics, Inc. (Nasdaq:MCRB) 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 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. SER-287 has successfully completed a Phase 1b study in patients with mild-to-moderate ulcerative colitis. Seres is developing SER-262, the first ever synthetic microbiome therapeutic candidate, in a Phase 1b study in patients with primary C. difficile infection. Seres is also developing SER-401 to augment the efficacy of immuno-oncology treatment. For more information, please visit Follow us on Twitter @SeresTx.


1. Wing W and Marina S, Microbial Biotechnology, 2017.
2. Theriot CM et al., mSphere, 2016.

Forward-looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including the ability of SER-109 to prevent the spread of antibiotic resistance, the ability of ECOSPOR III to support SER-109 approval, and the promise and potential impact of any of our microbiome therapeutics.

These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: we are not currently profitable and may never become profitable; our need for additional funding; our limited operating history; our unproven approach to therapeutic intervention; the lengthy, expensive, and uncertain process of clinical drug development; protection of our proprietary technology and the confidentiality of our trade secrets; potential lawsuits for, or claims of, infringement of third-party intellectual property or challenges to the ownership of our intellectual property; our patents being found invalid or unenforceable; and our ability to retain key personnel and to manage our growth. These and other important factors discussed under the caption “Risk Factors” in our Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission, or SEC, on August 2, 2018 and our other reports filed with the SEC could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.

Source: Seres Therapeutics, Inc.

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

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