On April 28, 2022 Miles W. McHugh notified the Horizon Therapeutics Public Limited Company of his intention to retire from his position as the Company's Senior Vice President, Chief Accounting Officer, effective as of November 11, 2022, and continue as an advisor to the Company afterwards. Also on April 28, 2022, in connection with the announcement of Mr. McHugh's retirement, Board of Directors appointed Patrick McIlvenny as Senior Vice President, Deputy Chief Accounting Officer, effective May 5, 2022, and Senior Vice President, Chief Accounting Officer, and principal accounting officer, effective as of Mr. McHugh's retirement on November 11, 2022. Mr. McIlvenny, joined the Company in February 2015 as Vice President, Corporate Controller.

Before joining the Company, Mr. McIlvenny served as Group Head of Corporate Reporting at Ardagh Group S.A. between 2013 and 2015, and in various finance roles of increasing responsibilities at Elan Corporation plc from 2005 to 2013.