X4 Pharmaceuticals to Host Investor Webinar Highlighting New Mavorixafor Phase 1b Data in Chronic Neutropenia

Webcast to take place on September 27 at 8:00 a.m. ET, followed by live Q&A

BOSTON, Aug. 31, 2022 (GLOBE NEWSWIRE) — X4 Pharmaceuticals, Inc. (Nasdaq: XFOR), a leader in the discovery and development of novel CXCR4-targeted small-molecule therapeutics to benefit people with diseases of the immune system, today announced that it will host an investor webinar to present and discuss new data from its Phase 1b trial evaluating its lead clinical candidate, mavorixafor, in patients with idiopathic, cyclic, and congenital neutropenia.

The event will include perspectives from patients and clinical experts on the unmet medical need and the opportunity for innovative treatment development. Members of X4 Pharmaceuticals’ management team will present clinical data on 25 patients from this fully enrolled trial and discuss mavorixafor’s potential to treat broader chronic neutropenia populations beyond its lead indication in Warts, Hypogammaglobulinemia, Infections, and Myelokathexis (WHIM) syndrome. A live Q&A will follow the formal presentations.

Webcast Details:

• Date: Tuesday, September 27, 2022
• Time: 8:00 – 9:00 a.m. ET
• To register for the event: Link

Following the conclusion of the live webcast, a replay of the event will be available within the investors’ section of the X4 Pharmaceuticals website at www.x4pharma.com.

About the Phase 1b Clinical Trial
The clinical trial (NCT04154488) is a proof-of-concept Phase 1b open-label, multicenter study designed to assess the safety and tolerability of daily, oral mavorixafor with or without G-CSF, in participants with chronic neutropenic disorders including severe congenital, idiopathic, or cyclic neutropenia. Participants were dosed with a single dose of oral mavorixafor to assess the magnitude of treatment response.

About X4 Pharmaceuticals
X4 Pharmaceuticals is a late-stage clinical biopharmaceutical company leading the discovery and development of novel therapies for people with diseases of the immune system. Our lead clinical candidate is mavorixafor, a first-in-class, small molecule antagonist of chemokine receptor CXCR4 that is being developed as a once-daily oral therapy. Due to mavorixafor’s ability to antagonize CXCR4 and improve the healthy maturation and mobilization of white blood cells, we believe that mavorixafor has the potential to provide therapeutic benefit across a wide variety of immune system diseases, including a range of chronic neutropenic disorders and certain types of cancer. The efficacy and safety of mavorixafor are being evaluated in a global Phase 3 clinical trial in patients with WHIM syndrome, a rare, inherited, primary immunodeficiency disease caused primarily by genetic mutations in the CXCR4 receptor gene. We are also studying mavorixafor in two Phase 1b clinical trials – one in patients with chronic neutropenic disorders including congenital, idiopathic, and cyclic neutropenia, and one concurrently with ibrutinib in patients with Waldenström’s macroglobulinemia (WM), a rare B-cell lymphoma. Further clinical development of mavorixafor in WM will now be subject to completing a strategic partnership as we focus our resources on advancing mavorixafor for the benefit of patients with chronic neutropenic disorders. We continue to leverage our insights into CXCR4 biology at our corporate headquarters in Boston, Massachusetts and at our research facility in Vienna, Austria. For more information, please visit our website at www.x4pharma.com.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of 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, statements regarding the clinical development and therapeutic potential of mavorixafor. Any forward-looking statements in this press release are based on management’s current expectations and beliefs. Actual events or results may differ materially from those expressed or implied by any forward-looking statements contained herein, including, without limitation, on account of uncertainties inherent in the initiation and completion of clinical trials and clinical development; the risk that trials and studies may not have satisfactory outcomes; the risk that the outcomes of preclinical studies or earlier clinical trials will not be predictive of later clinical trial results; the risk that initial or interim results from a clinical trial may not be predictive of the final results of the trial or the results of future trials; the potential adverse effects arising from the testing or use of mavorixafor or other product candidates; the risks related to X4’s ability to raise additional capital, and other risks and uncertainties, including those described in the section entitled “Risk Factors” in X4’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission (SEC) on August 4, 2022, and in other filings X4 makes with the SEC from time to time.

Contacts:
Daniel Ferry (investors)
Managing Director, LifeSci Advisors
daniel@lifesciadvisors.com
(617) 430-7576

Mónica Rouco Molina, Ph.D. (media)
Account Supervisor, LifeSci Communications
mroucomolina@lifescicomms.com