Mardi C. Dier has served as a member of Prelude’s Board of Directors since August 2020. Ms. Dier currently serves as the Chief Financial Officer and Chief Business Development Officer at privately held ACELYRIN, INC. She previously served as Chief Financial Officer of Ultragenyx. Ms. Dier also served as Executive Vice President and Chief Financial Officer, and also as Chief Business Officer, of Portola Pharmaceuticals, Inc., a biopharmaceutical company, from November 2013 and October 2018, respectively, until its acquisition by Alexion Pharmaceuticals in July 2020, and as a Senior Vice President and Chief Financial Officer from August 2006 to November 2013. From 2003 to 2006, Ms. Dier served as Vice President of Investor Relations at Chiron Corporation, a biopharmaceutical company. From 1994 to 2001, Ms. Dier served as a Director, Investment Banking at Prudential Securities, Inc., a securities firm. Ms. Dier previously served as a supervising senior accountant at the audit department of KPMG Peat Marwick, an accounting firm, from 1986 to 1990. Ms. Dier currently serves as a director of Health Care Royalty and a director and member of the audit committee of Oric Pharmaceuticals, Inc. and Synthekine. Ms. Dier received a B.S. in Biology from Stanford University and an M.B.A. from the Anderson Graduate School of Management at the University of California, Los Angeles.