Epizyme, Inc. (the “ Company”), entered into an Agreement and Plan of Merger (Merger Agreement), by and among the Company, Ipsen Pharma SAS (the Parent) and wholly owned subsidiary of Ipsen S.A. (Ipsen S.A), and Hibernia Merger Sub, Inc. (Purchaser) and wholly owned subsidiary of Ipsen Biopharmaceuticals, Inc. Further, pursuant to a unanimous written consent of the Company's Board of Directors, dated as of August 12, 2022, Grant Bogle was appointed as Chief Executive Officer of the Company, effective as of immediately following the consummation of the Merger.