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Seres Therapeutics conducts clinical trials to study the safety and efficacy of our investigational drugs for the treatment of diseases resulting from disruption to the microbiome, a condition known as dysbiosis.

Our proprietary microbiome therapeutics platform enables us to discover and develop our microbiome therapeutic candidates. These therapies are designed to target the functional deficiencies in a dysbiotic microbiome, and to deliver the keystone features needed to disrupt the disease microbiome and catalyze the transition of the gut microbiota to a healthy state.

These therapies have the potential to improve the lives of patients who are suffering from diseases for which the current course of treatment is inadequate, or for which no treatment exists.

We are currently conducting the following clinical trials:

  • SER-287: SERES-101 Study: A Phase 1b clinical study evaluating the safety and efficacy of SER-287 versus placebo, in adults with mild-to-moderate ulcerative colitis (UC) (SERES-101 Study)
  • SER-262: SERES-001 Study: A current Phase 1b study evaluating the safety and efficacy of SER-262 versus placebo, in adults with primary Clostridium difficile infection to prevent recurrence. (SER-262-001 Study)

The following clinical trials have been completed:

  • SER-109, Phase 1b open-label, single-arm, descending-dose study
  • SER-109, ECOSPORTM Study: A RandomizEd, Double Blind, Placebo COntrolled, Parallel Group Study of SER 109 to Prevent Recurrent ClOstRidium difficile Infection (SERES-004 Study)

Seres Thereputics is a proud collaborator to organizations raising awareness for and supporting research in our disease focus areas.

Learn more about these important organizations at the links below.

Clostridium difficile infection

Inflammatory Bowel Disease

Clinical Trials

Review our ongoing clinical trials


Microbiome Overview

Learn more about the microbiome


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