Seres Therapeutics Business Summary

Seres Therapeutics, Inc. (MCRB) is a clinical-stage biotechnology company that has transitioned from a commercial-stage entity to a leaner, R&D-focused organization following the September 2024 sale of its VOWST business to Nestlé Health Science. The company generates revenue primarily through structured installment payments from this divestiture—including a $50 million payment in January 2025 and a $25 million payment in July 2025—alongside potential future sales-based milestones totaling up to $275 million and royalties. As of February 12, 2026, Seres has implemented a significant strategic pivot, pausing its lead SER-155 program to prioritize high-value, earlier-stage candidates for inflammatory and immune (I&I) diseases such as ulcerative colitis and Crohn’s disease. In the competitive microbiome landscape, Seres contends with Ferring Pharmaceuticals, Vedanta Biosciences, and MaaT Pharma; while it was the first to achieve FDA approval for an oral microbiome therapeutic, it currently occupies a specialized niche focused on cultivated live biotherapeutic consortia for medically vulnerable populations. The company is led by co-CEOs Thomas DesRosier and Marella Thorell, who assumed their roles in August 2025 following the departure of longtime CEO Eric Shaff. DesRosier previously served as the company’s Chief Legal Officer with a pedigree at ARIAD and Genzyme, while Thorell, also the CFO, brought extensive financial leadership from Evelo Biosciences and Centessa Pharmaceuticals. The executive team includes Chief Scientific Officer Dr. Matthew Henn, a pioneer in microbial genomics, and Chief Technology Officer Dr. David Ege, formerly of Merck. Seres was founded in 2010 by Flagship Pioneering, with a founding team including Dr. David Berry, Dr. Noubar Afeyan, and Dr. Geoffrey von Maltzahn. The company maintains a strong institutional backbone with Independent Chairman Stephen Berenson and continued strategic backing from Flagship Pioneering and Nestlé Health Science.