Keith M. Gottesdiener, MD | Chief Executive Officer
Dr. Gottesdiener is Chief Executive Officer of Rhythm. He joined Rhythm after 16 years at Merck Research Laboratories. Dr. Gottesdiener joined Merck early clinical development in 1995, helping to transition compounds from the bench to the bedside and through to proof of concept. He held positions of increasing responsibility, eventually leading the early clinical development/clinical pharmacology department at Merck from 2001 through early 2006. From 2006-2011, he was a leader of Merck's late clinical development organization, first overseeing the development of Merck's infectious diseases and vaccine products through pivotal trials, registration, and life cycle management, including Gardasil™ (HPV Vaccine), Rotateq™ (rotavirus vaccine), Zostavax™ (zoster vaccine) and Isentress™ (HIV integrase inhibitor), among others. In 2008, Dr. Gottesdiener was appointed Late Stage Therapeutic Group Leader, and in that role led the late-stage clinical development efforts of Merck across all therapeutic areas. After the merger with Schering Plough in 2009, he continued as co-head of late development, most recently playing a leading role in the regulatory activities leading to the approval of boceprevir for Hepatitis C. Dr. Gottesdiener received his BA from Harvard College and his MD from the University of Pennsylvania. He completed his residency and fellowship at the Brigham and Women's Hospital-Beth Israel Medical Center-Dana Farber Cancer Institute Children's Hospital programs. After his fellowship, Dr. Gottesdiener did postdoctoral research in the laboratory of Dr. Jack Strominger at Dana Farber Cancer Institute working on the molecular immunology of the T-cell receptor. In 1986, he joined the faculty as an assistant professor at Columbia University, started an independent research laboratory with NIH RO-1 funding, focusing on gene transcription, and was Associate Clinical Professor of Medicine at the time he left to join Merck in 1995.

Bart Henderson, MBA | President & Founder
Mr. Henderson is President and a Founder of Rhythm. Previously, he was Entrepreneur-in-Residence at MPM Capital and Chief Business Officer of Radius, where he was a founding employee and led the acquisition of four pipeline programs. Mr. Henderson founded sales and marketing at Vertex when the company launched its first product, broadened its product pipeline, signed corporate partnerships valued at $1.2 billion, and raised $715 million in financing. He founded business development at Microbia (now Ironwood Pharmaceuticals), which signed its first corporate partnerships and significantly expanded its pipeline during his tenure. In addition, Mr. Henderson held marketing management positions at Amgen and Merck. He holds an MBA from Dartmouth’s Tuck School of Business and a BA from Amherst College.

Elizabeth Stoner, MD | Chief Development Officer & Founder
Dr. Stoner is Chief Development Officer and a Founder of Rhythm, and a Managing Director of MPM Capital. Previously, she had a 22-year career at Merck Research Laboratories that culminated in the position of Senior Vice President of Global Clinical Development Operations, with responsibility for the company's clinical development activities in more than 40 countries. Dr. Stoner also oversaw the clinical development activities of Merck's Japanese partner, Banyu; led clinical development for the Merck/Schering-Plough Joint Venture for Zetia/Vytorin; and played a critical leadership role in Merck's efforts to transform its worldwide clinical development operations. Earlier in her career at Merck, Dr. Stoner led the Proscar clinical development program from inception, establishing Merck as a leader in the field of prostate disease. As Endocrine Therapeutic Head, Dr. Stoner's responsibilities included steroid and lipid metabolism as well as clinical research programs focused on the growth hormone, secretagogue. Prior to her tenure at Merck, Dr. Stoner was an Assistant Professor of Pediatrics at Cornell University Medical College. She received a BS in Chemistry from Ottawa University (KS), an MS in Chemistry from the State University of New York at Stony Brook, and an MD from Albert Einstein College of Medicine.

Lex H.T. Van der Ploeg, PhD | Chief Scientific Officer
Dr. Van der Ploeg is Chief Scientific Officer of Rhythm. He has more than 25 years of drug development experience focused on obesity, metabolic disorders, oncology, and neurodegenerative diseases. Before joining Rhythm, he was Senior Vice President of Integrative Medicine and Translational Science at Abraxis Bioscience and Head of R&D at Abraxis Health; both companies were acquired by Celgene Corporation. Prior to that, he held R&D leadership roles at Merck Research Laboratories (MRL) directing drug development programs in metabolism, oncology, and neurodegenerative diseases as Vice President, Basic Research and Site Head, MRL Boston; Site Head, MRL San Diego; and Head, Obesity Research for Merck Rahway and Banyu, Japan. Previously, Dr. Van der Ploeg was a tenured faculty member in the Department of Genetics and Development at Columbia University. He has received numerous awards and grants for his research and has published more than 200 peer-reviewed research papers. Dr. Van der Ploeg is a named inventor on more than 50 patents and patent applications. He received an MS in Biochemistry from the University of Amsterdam and a PhD in Biochemistry/Enzymology/Genetics from the University of Amsterdam/Netherlands Cancer Institute.