Exhibit 99.1 X4 Pharmaceuticals Reports First-Quarter 2024 Financial Results and Provides Corporate Updates U.S. launch underway for XOLREMDI™ (mavorixafor) in WHIM syndrome XOLREMDI Phase 3 4WHIM clinical trial data published online in Blood, the journal of the American Society of Hematology Presentation of interim clinical data from the ongoing mavorixafor Phase 2 trial in chronic neutropenia expected at a planned company investor event in June 2024 Conference call to be hosted today at 8:30 a.m. ET BOSTO ...