Steve van Os leads UPyTher’s clinical development and regulatory strategy. He is an accomplished medical executive with 30 years of experience in oncology drug development within the pharmaceutical and biotech industries. Prior to joining UPyTher, he served as Chief Medical Officer at Antev Ltd. and held multiple senior leadership roles at Astellas Pharma, where he co-chaired the Pfizer/Astellas alliance and helped lead the global development and approval of the blockbuster prostate cancer therapy Xtandi, across nearly 100 countries. Earlier in his career, he held positions at Schering-Plough, Organon International, and Yamanouchi Europe. Steve earned his medical degree from Utrecht University and is a member of the Dutch Board for Pharmaceutical Medicine.