 CAMBRIDGE, Mass.--BUSINESS WIRE--Seres Therapeutics, Inc. Nasdaq: MCRB, a leading microbiome therapeutics company, today announced it has achieved enrollment of 300 subjects with the ECOSPOR IV open-label study evaluating SER-109, an investigational oral microbiome therapeutic for recurrent C. difficile infection rCDI. The target enrollment of a minimum of 300 subjects for the SER-109 safety database was reached in conjunction with a prior completed Phase 3 study, ECOSPOR lll. Seres is re 