Boston — Ironwood Pharmaceuticals has appointed Jeffrey Silber, M.D., as Chief Medical Officer and Head of Research and Drug Development, succeeding Michael Shetzline, M.D., who is retiring after a 30-year career in gastrointestinal research and patient care.
Silber will oversee Ironwood’s Research and Drug Development, Regulatory Affairs and Medical Affairs organizations and report to Tom McCourt, Chief Executive Officer of Ironwood Pharmaceuticals. He will join the company on July 20, 2026.
Shetzline will remain an adviser to the biotechnology company to support the leadership transition.
Ironwood also said its confirmatory Phase 3 STARS-2 clinical trial evaluating apraglutide in patients with short bowel syndrome with intestinal failure was initiated in June and is now actively recruiting participants.
“I would like to congratulate Mike on a distinguished 30-year career and thank him for his leadership and many contributions, including building strong R&D, Regulatory Affairs and Medical Affairs organizations at Ironwood – most recently leading the team through the initiation of STARS-2,” McCourt said. “It’s a pleasure to welcome Jeff to our leadership team. His broad medical and scientific leadership expertise will help us build on the strong foundation we already have in place, supporting the continued growth of LINZESS and helping Ironwood bring apraglutide to patients as quickly as possible.”
Silber joins Ironwood from Vedanta Biosciences, where he has served as Chief Medical Officer since 2020 and led the research and clinical development of microbiome-based oral therapies for inflammatory and infectious gastrointestinal diseases.
“I am excited to join Ironwood at such an important time for the company and to help advance apraglutide. Based on the positive Phase 3 STARS data, I believe apraglutide has the potential to be a best-in-class therapy for patients with SBS-IF who continue to face significant unmet needs,” said Jeffrey Silber, M.D., Chief Medical Officer and Head of Research and Drug Development at Ironwood Pharmaceuticals. “I look forward to working with the team to continue executing the STARS-2 trial as we work to bring apraglutide to patients living with SBS-IF swiftly.”
Before joining Vedanta, Silber was Senior Vice President in Clinical Development and Head of Development Sciences at EMD Serono/Merck KGaA. In that role, he oversaw global program leadership, patient safety, fertility and endocrine clinical research, biostatistics and epidemiology, and translational medicine.
He previously served as Vice President and Head of Strategic Portfolio Development at AbbVie. During a 16-year tenure at Merck & Co., Silber held several leadership roles across vaccines, anti-infectives and neuroscience, ultimately serving as Vice President and Therapeutic Area Head, Vaccine Clinical Research.
Silber was also an Assistant Professor of Medicine at UMDNJ/Robert Wood Johnson School of Medicine in Camden, New Jersey.
He earned a B.A. in biology from Harvard University and an M.D. from the Albert Einstein College of Medicine. He completed training in internal medicine at NYU Medical Center/Bellevue Hospital and in infectious diseases at the Hospital of the University of Pennsylvania.
