X4 Pharmaceuticals, Inc

X4 Forward Looking Statements

This press release contains forward-looking statements within the meaning of applicable securities laws, including the Private Securities Litigation Reform Act of 1995, as amended. These statements may be identified by the words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “target,” or other similar terms or expressions that concern X4’s expectations, strategy, plans, or intentions. Forward-looking statements include, without limitation, implied or express statements regarding the initiation, timing, progress, and results of our current and future preclinical studies and clinical trial; the timing and period during which the results of the trials will become available and reported, as well as our research and development programs; market opportunities for X4’s product candidates, including potential benefits from partnerships; expectations regarding the commercial potential of mavorixafor and ongoing engagement and feedback from regulatory authorities; and the sufficiency of X4’s cash resources and pro forma cash resources, including the potential impact of the 2025 strategic restructuring, and expectations regarding X4’s cash runway.

Any forward-looking statements in this press release are based on management’s current expectations and beliefs. These forward-looking statements are neither promises nor guarantees of future performance, and are subject to a variety of risks and uncertainties, many of which are beyond X4’s control, which could cause actual results to differ materially from those contemplated in these forward-looking statements, including the risks that: X4’s restructuring activities may be more costly or time-consuming than expected or may not achieve their intended results and savings; X4’s future financial performance and position may not improve resulting in difficulties in implementing X4’s business strategy, and plans and objectives for future operations; the expected decrease in annual spending could negatively impact X4’s commercial plans and strategy for mavorixafor; the expected sufficiency of X4’s existing cash resources and runway may not be accurate resulting in the need for additional financing sooner than anticipated or unexpected liquidity constraints; the internal and external costs required for X4’s ongoing and planned activities, and the resulting impact on expense and use of cash, may be higher than expected, which may cause the company to use cash more quickly than expected or to change or curtail some of X4’s plans or both; the expected availability, content, and timing of clinical data from X4’s ongoing clinical trials of mavorixafor may be delayed or unavailable, including its ongoing Phase 3 clinical trial; trials and studies may be delayed and may not have satisfactory outcomes, earlier trials and studies may not be predictive of later trials and studies, including clinical results from the completed Phase 2 clinical trial and research focused on assessing the ability of mavorixafor monotherapy to durably increase absolute neutrophil count in patients with chronic neutropenic; the design and rate of enrollment for clinical trials, including the current design of the ongoing Phase 3 clinical trial evaluating mavorixafor in certain chronic neutropenic disorders may not enable successful completion of the trial(s); the commercial opportunity for mavorixafor in chronic neutropenic disorders may be smaller than anticipated; X4 may be unable to obtain and maintain regulatory approvals; the company may experience uncertainties inherent in the initiation and completion of preclinical studies and clinical trials and clinical development; adverse safety effects might arise from the testing or use of X4 product and product candidates; the need to align with collaborators may hamper or delay development and commercialization efforts or increase costs; business may be adversely affected and costs may increase if any of the company’s key collaborators fails to perform its obligations or terminates the collaboration; X4’s ability to advance and commercialize and increase sales in mavorixafor to treat chronic neutropenia or to optimize the U.S. promotion of XOLREMDI (mavorixafor), approved for the treatment of WHIM; and other risks and uncertainties, including those described in the section entitled “Risk Factors” in X4’s Annual Report on X4’s Form 10-K expected to be filed with the Securities and Exchange Commission (SEC) on March 25, 2025, and in other filings X4 makes with the SEC from time to time. X4 undertakes no obligation to update the information contained in this press release to reflect new events or circumstances, except as required by law.

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