Ellie Im, M.D. joined Crescent as chief medical officer in April 2025, bringing deep experience in oncology clinical development and operations across different modalities, including ADCs and bispecific antibodies. Most recently, Dr. Im was senior vice president of clinical development at Centessa Pharmaceuticals where she oversaw clinical development, clinical pharmacology, biostatistics, project management and safety across multiple therapeutic areas, including oncology. Prior to joining Centessa, she was senior vice president, clinical development and operations at Mersana Therapeutics where she led teams in clinical development and clinical operations. Previously, Dr. Im was clinical development lead and senior medical director at Tesaro, an oncology-focused company that was later acquired by GlaxoSmithKline, where she led the clinical development for JEMPERLI^®. Earlier in her career, she served as medical director for Merck and led clinical development for KEYTRUDA^®. Dr. Im is a medical oncologist and holds an M.D. from Catholic University College of Medicine, South Korea. She is board certified in internal medicine and medical oncology, and a member of the American Society of Clinical Oncology and Hematology.