Prothena Corporation plc announced the appointment of Daniel G. Welch to its Board of Directors as an independent director and Chair Designate following a comprehensive search process in connection with the board?s regular succession planning. Upon election by the shareholders at Prothena?s Annual General Meeting later this year, the Board intends to appoint Mr. Welch as Chair of the Board. The planned transition is in anticipation of the conclusion of Dr. Lars Ekman?s successful 11-year tenure as Chair during which he made significant contributions to the Company?s growth and success.

Dr. Ekman will step down as Chair and continue to serve on the board as Chair Emeritus, following the anticipated appointment of Mr. Welch. The entire Prothena Board expresses their sincere gratitude for Dr. Ekman?s valuable service as Chair. Additionally, Dr. Anders Harfstrand, whose current board term will expire at the Annual Meeting, is not standing for re-election at the Annual Meeting.

Mr. Welch serves as the chair of the boards of Structure Therapeutics Inc., Nuvation Bio Inc., and Ultragenyx Pharmaceuticals Inc. He recently served as a director of Seagen Inc. which was acquired by Pfizer in December 2023. He previously served as chair of the board of AveXis Inc. (acquired by Novartis in 2018), and as a director of Intercept Pharmaceuticals Inc. and Hyperion Therapeutics (acquired by Horizon Pharma in 2015). Prior to these roles he served as an executive partner at Sofinnova Ventures, as CEO and president of InterMune Inc. (acquired by Roche Holdings in 2014), as chair of the board of InterMune, as chair of the board and CEO of Triangle Pharmaceuticals Inc. (acquired by Gilead Sciences in 2003), and as president of the pharmaceutical division of Elan Corporation, PLC.

Mr. Welch earned his B.A. from the University of Miami and his M.B.A. from the University of North Carolina. With Dr. Anders Harfstrand not standing for re-election at the Annual Meeting, the Board plans to reduce the size of the Board to ten members immediately after the Annual Meeting. Dr. Harfstrand has been a director since 2015 and the entire Prothena Board acknowledges and appreciates his positive impact during his service.