MCRB News & Events

Reports FY25 revenue $789k. "As highlighted in our recent announcements, we are prioritizing our promising inflammatory and immunology biotherapeutics portfolio, including SER-603 for inflammatory bowel disease," said Richard Kender, Executive Chair and interim CEO of Seres. "We are on track to report clinical data from the fully enrolled investigator-sponsored study at Memorial Sloan Kettering Cancer Center evaluating SER-155 to treat immune checkpoint inhibitor-related enterocolitis in the second quarter of this year. This serious condition affects up to 50% of immune checkpoint-treated cancer patients, with rates varying based on cancer drug and treatment regimen, and represents a sizable therapeutic and commercial opportunity. Additionally, our SER-155 program for the prevention of serious bloodstream infections in patients undergoing allo-HSCT for blood cancer is Phase 2 ready, and we continue to seek funding to support further development."

Seres Therapeutics announced the appointment of Richard Kender as executive chair and interim CEO. Kender has served on the Seres board of directors since September 2014. Tom DesRosier and Marella Thorell, previously co-CEOs of Seres, will continue to serve as chief legal officer and CFO, respectively. Stephen Berenson, outgoing Seres board chairman, stated, "On behalf of the entire board, I wish to thank Tom and Marella for their continued strong leadership. They provided essential continuity of leadership; drove the organization to advance SER-155 to Phase 2 readiness; and shaped the strategy for the next phase of Seres' development, including the Company's engagement with potential strategic partners. We are pleased to continue to work with both of them in their roles as Chief Legal Officer and Chief Financial Officer."

Seres Therapeutics announced that, following advancement of key startup activities for the SER-155 Phase 2 study in allo-HSCT, including the submission of a final protocol to the FDA, study site evaluation and qualification with its CRO, and manufacturing of Phase 2 study drug substance, Seres is pausing additional investment in that program and will shift its operational focus to high-value earlier-stage pipeline programs while continuing to seek funding for the SER-155 Phase 2 study. Seres also announced additional measures to reduce operating costs, including a workforce reduction of approximately 30%. As a result of these and other runway extension actions, and based on current operating plans, the Company expects to extend its cash runway through the third quarter of 2026, thereby providing additional opportunities to advance development of its live biotherapeutic programs for inflammatory and immune diseases, and pursue potential collaborations. The company said, "The SER-155 program has meaningfully advanced Seres' understanding of how microbes in the GI tract functionally modulate pathways at the mucosal barrier-immune interface associated with inflammatory and immune-related diseases. Accordingly, the Company's strategy moving forward will prioritize advancing its early-stage programs, including SER-603 that targets inflammatory and immune indications such as ulcerative colitis, Crohn's disease, and immune checkpoint related enterocolitis. Discussions are ongoing with counterparties related to potential collaborations in these areas." "Seres has taken extensive steps to prepare for a robust SER-155 Phase 2 study in allo-HSCT, including submission of a final protocol to the FDA, advancement of drug substance manufacturing, selection of a CRO and engagement with prospective study sites. As we shift our operational focus to our promising earlier-stage pipeline, we are now in a position to streamline our organization and cost structure," said Thomas DesRosier and Marella Thorell, co-CEOs of Seres. "These cost reduction initiatives and other actions are expected to extend our cash runway through the end of the third quarter of this year, supporting continued development of our programs for inflammatory and immune-related diseases, with targets validated by our previously reported preclinical and clinical datasets, and providing additional time to secure funding for our SER-155 Phase 2 study. In addition, as we pursue earlier stage programs with the greatest opportunity, such as those targeting inflammatory bowel disease, we are exploring collaborations to provide additional capital to the Company. We are very grateful for the many contributions of our departing team members."

Seres Therapeutics announced the publication of two manuscripts in Nature Medicine and the Journal of Infectious Diseases highlighting new insights into the functional mechanism and clinical impact of VOWST. Together, these publications provide further validation of the Company's Live Biotherapeutics Products, LBPs, approach and inform the continued development of Seres' pipeline of next-generation LBPs, including its lead investigational candidate, SER-155. The Nature Medicine article, titled "The impact of an oral purified microbiome therapeutic on the gastrointestinal microbiome", confirmed Seres pharmacological hypotheses from earlier VOWST studies, with higher VOWST dosing associated with enhanced pharmacokinetics, as assessed by faster and more robust therapeutic species engraftment in the gut. A publication in the Journal of Infectious Diseases, titled "Comparability of Gastrointestinal Microbiome and Bile Acid Profiles in Patients With First or Multiply Recurrent Clostridioides difficile Infection", reported a post hoc analysis of the ECOSPOR IV Phase 3 trial, with data demonstrating that the underlying functional disease etiology is consistent in both first and multiply recurrent CDI patient populations, with VOWST demonstrating similar efficacy and drug pharmacology across the broad patient population.