On July 21, 2021, of the previously announced acquisition of Alexion Pharmaceuticals, Inc., pursuant to the Agreement and Plan of Merger dated as of December 12, 2020, by and among Alexion, AstraZeneca PLC, AstraZeneca Rare Disease Holdings Inc. (f/k/a Delta Omega Sub Holdings Inc.), a Delaware corporation and a wholly owned subsidiary of AstraZeneca (“ Bidco”), Delta Omega Sub Holdings Inc. 1, a Delaware corporation and a direct, wholly owned subsidiary of Bidco (“ Merger Sub I”) and Alexion Rare Disease LLC (f/k/a Delta Omega Sub Holdings LLC 2), a Delaware limited liability company and a direct, wholly owned subsidiary of Bidco (“ Merger Sub II”). Pursuant to the terms of the Merger Agreement, (1) Merger Sub I merged with and into Alexion (the “ First Merger”), with Alexion surviving the First Merger as a wholly owned subsidiary of Bidco (the “ First Surviving Corporation”), and (2) immediately following the effective time of the First Merger (the “ First Effective Time”), Alexion merged with and into Merger Sub II (such effective time, the “ Second Effective Time”, such merger, the “ Second Merger” and, together with the First Merger, the “ Mergers”), with Merger Sub II surviving the Second Merger as a wholly owned subsidiary of Bidco and an indirect wholly owned subsidiary of AstraZeneca (the “ Surviving Company”). On July 22, 2021, as a result of an internal restructuring at AstraZeneca, the Surviving Company merged with and into Bidco, with Bidco surviving the Upward Merger as an indirect wholly owned subsidiary of AstraZeneca and being renamed “Alexion Pharmaceuticals, Inc.” (“ New Alexion”). By virtue of the Mergers, all of the directors of Alexion ceased to be directors on the board of directors of Alexion and any and all committees thereof, effective as of the First Effective Time. From and after the Third Effective Time, the directors and officers of Bidco immediately prior to the Third Effective Time became the directors and officers of New Alexion. Each of Messrs. Ludwig Hantson, Chief Executive Officer; John Orloff, Executive Vice-President, Global Head of Research and Development; and Brian Goff, Executive Vice President, Chief of Commercial and Global Operations Officer; and Ms. Ellen Chiniara, Executive Vice President, Chief Legal Officer, and Corporate Secretary (the “ Executives”) entered into separation agreements with Alexion, providing for the termination of their employment effective as of the Closing Date. The separation agreements generally provide for separation benefits in accordance with the employment agreements that governed each Executives’ employment relationships.