Stockwatch: The Fall, Rise And Challenges Of Seres' Microbiome Therapy

Seres Therapeutics, Inc.’s single positive Phase III study for its first microbiome product, SAR-109, following as it did a failed Phase II trial, may have put a different complexion on its imminent biologic license application filing to the US Food and Drug Administration, but traditional safety, regulatory and commercial hurdles remain.

Seres Therapeutics emerged as the summer 2015 biotech bubble burst with the aim of developing the first approved microbiome drug. The microbiome is our normal flora that comprises a diverse and balanced population of microorganisms which helps nutrients to be absorbed and keeps disease-causing microorganisms at bay. If this healthy homeostatic balance is disrupted − for example by broad-spectrum antibiotics – pathogens can overgrow and result in disease. Restoring that balance has in the past been achieved by more specific antibiotic therapies or even probiotics