Engineering Medicines To Improve Patient Care About Us Steve Mahoney President and Chief Executive Officer Steve Mahoney became Viridian’s President and Chief Executive Officer and a member of the Board of Directors in October 2023. Steve has more than two decades of experience in a variety of operational, financial, commercial, legal and transactional roles in companies of different sizes and stages. He has been successful scaling organizations from founding team through commercial stage. Prior to joining Viridian, Steve was the Chief Financial and Operating Officer of Magenta Therapeutics, where he drove operational excellence and disciplined capital allocation focus to high priority programs. Previously, Steve was part of the founding team of Kiniksa Pharmaceuticals, where he served as President and Chief Operating Officer. Prior to Kiniksa, he was Chief Commercial Officer of Synageva Biopharma, where he held roles of increasing responsibility in operations, commercial launch preparation, legal and corporate development. Steve was also a commercial attorney with Genzyme Corporation for approximately ten years. Prior to Genzyme, Steve was a corporate attorney with Mintz Levin. He holds a Master’s in Business Administration (MBA) from Boston College’s Carroll School of Management, a Juris Doctor (JD) from Boston College Law School, and a Bachelor of Arts from Colorado College. He serves on the board of directors of Vesselon, Inc., a private company.