Clinical trialsCompany release

Seres plans Q1 2027 FDA submission for SER-155 enterocolitis prevention study

🇺🇸 Seres Therapeutics, Inc. (MCRB) · Wed 04 Nov 2026

The company said it expects to submit the design of its next SER-155 study to the FDA in the first quarter of 2027, with progress dependent on funding.

Seres Therapeutics reported its third-quarter 2026 results on 4 November and said it expects to submit the design of its next SER-155 study to the US Food and Drug Administration in the first quarter of 2027.

The study would test SER-155, a live biotherapeutic, as prevention of enterocolitis related to immune checkpoint inhibitors (irEC). The company points to an investigator-sponsored trial in patients with moderate-to-severe irEC as the basis for the plan.

In that trial, 12 of 15 patients had an immunosuppressive-free clinical response, and no drug-related serious adverse events were reported, according to the company.

Seres said progress depends on funding. It is seeking partnerships for this programme and for a separate programme in bloodstream infections in patients undergoing allogeneic haematopoietic cell transplantation (allo-HCT), which it describes as Phase 2-ready.

What it means for your team

  • The planned submission is of a study design to the FDA; no approval or regulatory decision is involved at this stage.
  • The preliminary evidence comes from a small investigator-sponsored trial of 15 patients, so it should be read with caution.
  • Funding and partnering are explicit conditions for progress, so timelines may shift.
  • Teams tracking live biotherapeutics or immuno-oncology safety may wish to follow how prevention of irEC is framed in the eventual study design.

Company's press release (SEC filing): Seres Therapeutics, Inc. ↗

Article written by VigiEye from the official source (Seres Therapeutics, Inc.). Claims are the company's own. AI-assisted; check the source before acting.

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