Seres reports early data showing SER-155 eases ICI-related enterocolitis without systemic immunosuppressives in MSK trial

• Seres reported early top-line results from an MSK investigator-sponsored trial of SER-155 in immune checkpoint inhibitor-related enterocolitis.
• Primary endpoint met: 12 of 15 patients (80%) had immunosuppressive-free clinical response in diarrhea at Day 15; 5 of 15 (33%) reached remission.
• At Day 43, 5 of 15 (33%) maintained response; 2 of 15 (13%) maintained remission; remaining Day 15 responders used GI-targeted immunosuppressives.
• No drug-related serious adverse events through Day 43; no bloodstream infections reported.
• Company evaluating next development steps for irEC; pursuing partners while seeking funding to advance a Phase 2 SER-155 study in allo-HCT.

Disclaimer: This news brief was created by Public Technologies (PUBT) using generative artificial intelligence. While PUBT strives to provide accurate and timely information, this AI-generated content is for informational purposes only and should not be interpreted as financial, investment, or legal advice. Seres Therapeutics Inc. published the original content used to generate this news brief via GlobeNewswire (Ref. ID: 202607080700PRIMZONEFULLFEED9758603) on July 08, 2026, and is solely responsible for the information contained therein.