Seres Therapeutics unveils promising preclinical data for SER-603, a new treatment candidate for inflammatory bowel disease.

Seres Therapeutics presented preclinical data at Digestive Disease Week 2026 supporting SER-603, a next-generation live biotherapeutic designed to treat inflammatory bowel disease (IBD). SER-603 targets microbial functions linked to mucosal healing and inflammation, aiming to improve gut barrier integrity and reduce inflammatory bacteria. The therapy complements existing treatments and is being advanced through IND-enabling activities with potential for both monotherapy and combination use. This development highlights Seres' innovative approach to microbiome-based therapies for IBD, with ongoing efforts to stratify patients using microbiome biomarkers for better treatment outcomes.