• 5 November 2019
    X4 Pharmaceuticals Initiates Phase 1b Clinical Trial of Mavorixafor for the Treatment of Severe Congenital Neutropenia

    X4 Pharmaceuticals, Inc. (Nasdaq: XFOR), a clinical-stage biopharmaceutical company focused on the development of novel therapeutics for the treatment of rare diseases, today announced the initiation of a Phase 1b clinical trial of mavorixafor (X4P-001) for the treatment of Severe Congenital Neutropenia (SCN), a group of rare blood disorders characterized by abnormally low levels of neutrophils.

    The Phase 1b trial is a 14-day, proof-of-concept trial designed to assess the safety and tolerability of daily, oral mavorixafor in participants with SCN and other selected congenital neutropenia disorders. In addition, the trial will evaluate the neutrophil response in this patient population as an independent agent or in combination with granulocyte-colony stimulating factor (G-CSF). The trial will enroll up to 45 patients in total.

    “SCN often presents as a diagnostic challenge for physicians, and there is an unmet clinical need for targeted treatment options that may be better tolerated than existing therapies. Current treatments are limited to non-specific stimulation of the bone marrow with daily injections of G-CSF and antibiotics for infections, although G-CSF can cause bone pain as well as injection site reactions. Additionally, in rare instances, high chronic doses of G-CSF have been associated with myelodysplasia and acute myeloid leukemia in this patient population,” said Lynne Kelley, M.D., FACS, Chief Medical Officer of X4 Pharmaceuticals. “We are interested in exploring whether mavorixafor may provide a safe and well-tolerated treatment alternative for these patients.”

    “We’re thrilled to initiate this clinical trial with mavorixafor for patients with SCN as we continue to validate the therapeutic potential of this potentially first-in-class drug candidate for the treatment of rare diseases,” said Paula Ragan, Ph.D., President and Chief Executive Officer of X4 Pharmaceuticals. “We believe mavorixafor’s unique mechanism of action may have application across a variety of primary immunodeficiency diseases in which CXCR4-associated immune cell trafficking is disrupted. We look forward to advancing the clinical development of mavorixafor to potentially benefit SCN patients who currently have limited treatment options.”