Horizon Therapeutics Announced Acquisition By Amgen Approved By The High Court Of Ireland

-8-K

As previously disclosed, on December 11, 2022, Horizon Therapeutics plc (“Horizon”), Amgen Inc. (“Amgen”) and Pillartree Limited, a whollyowned subsidiary of Amgen (“Acquirer Sub”), entered into a Transaction Agreement pursuant to which, among other things, Acquirer Sub willacquire the entire issued ordinary share capital of Horizon (the “Acquisition”) through a court-sanctioned scheme of arrangement underChapter 1 of Part 9 of the Irish Companies Act 2014 (the “Scheme”).On October 5, 2023, the High Court of Ireland (the “Court”) sanctioned the Scheme. Completion of the Acquisition remains subject to thedelivery to the Registrar of Companies in Ireland of a copy of the order of the Court sanctioning the Scheme. Assuming that a copy of theCourt order is processed and made available to Horizon by no later than the morning of October 6, 2023 (Irish time), the Scheme is expectedto become effective on October 6, 2023.