News & Events

Entry into a Material Definitive Agreement. Amendment of Asset Purchase Agreement On June 2, 2026, Seres Therapeutics, Inc. (the “Company”) entered into Amendment No. 1 (the “APA Amendment”) to the Asset Purchase Agreement, dated as of August 5, 2024 (as previously amended by that certain Letter Agreement, dated September 30, 2024 and that certain Letter Agreement, dated December 31, 2024, the “Purchase Agreement”), by and between the Company and Société des Produits Nestlé S.A., a société an…

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensation Arrangements of Certain Officers. On May 30, 2026, Hans-Juergen Woerle, M.D., Ph.D. resigned from his position as a member of the board of directors of Seres Therapeutics, Inc. (the “Company”) and on the committees on which he serves, effective May 31, 2026. Dr. Woerle’s departure is not due to any disagreement with the Company on any matter relating to the Company’s operations, po…

of this Current Report, including Exhibit 99.1 attached hereto, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

Results of Operations and Financial Condition. On March 12, 2026, Seres Therapeutics, Inc. (the “Company”) announced its financial results for the quarter and year ended December 31, 2025 and provided operational updates. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K (the “Current Report”).

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. On February 27, 2026, the Board of Directors (the “Board”) of Seres Therapeutics, Inc. (the “Company”) appointed Richard N. Kender, a current member of the Board, to serve as Executive Chair of the Board and as Interim Chief Executive Officer of the Company, Matthew Henn, Ph.D., the Company’s Chief Scientific Officer, to the additional role of Pres…

Results of Operations and Financial Condition. On November 5, 2025, Seres Therapeutics, Inc. (the “Company”) announced its financial results for the quarter ended September 30, 2025 and provided operational updates. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K (the “Current Report”).

Other Events. On September 23, 2025, Seres Therapeutics, Inc. (the “Company”) announced actions to reduce operating costs in order to extend its cash runway to provide additional opportunities to advance its strategic priorities. In this announcement, the Company reported that it was reducing its workforce by approximately 25% (including reductions that were effective in August 2025), and the workforce reduction is expected to result in cash charges of approximately $1.0 to $1.4 million, prim…

Results of Operations and Financial Condition. On August 6, 2025, Seres Therapeutics, Inc. (the “Company”) announced its financial results for the quarter ended June 30, 2025 and provided operational updates. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K (the “Current Report”).

Results of Operations and Financial Condition. On May 7, 2025, Seres Therapeutics, Inc. (the “Company”) announced its financial results for the quarter ended March 31, 2025 and provided operational updates. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K (the “Current Report”).

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. As reported below under

Other Events. On April 10, 2025, at the Annual Meeting, the stockholders of the Company approved amendments to the Company’s Certificate of Incorporation to effect a reverse stock split of all outstanding shares of the Company’s common stock, at a ratio ranging from any whole number between 1-for-5 and 1-for-50, with the exact ratio as determined by the Board in its discretion, subject to the Board’s authority to abandon such amendments. On April 10, 2025, the Board approved a reverse stock s…

Results of Operations and Financial Condition. On March 13, 2025, Seres Therapeutics, Inc. (the “Company”) announced its financial results for the quarter and year ended December 31, 2024 and provided operational updates. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K (the “Current Report”).

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. On February 22, 2025, Lisa von Moltke, M.D. notified Seres Therapeutics, Inc. (the “Company”) of her intention to resign as the Executive Vice President and Chief Medical Officer of the Company, effective as of March 14, 2025. Dr. von Moltke has accepted a position as Chief Medical Officer and Head of Research and Development of a U.S. biopharmaceu…

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. On February 4, 2025, the Board of Directors (the “Board”) of Seres Therapeutics, Inc. (the “Company”) increased its size to provide for a total of nine directors authorized to serve on the Board and appointed Hans-Juergen Woerle, M.D., as a Class III director of the Company, effective immediately. Dr. Woerle has been appointed to serve on the Scien…