X4 is focused on restoring healthy immune system function by developing novel therapeutics for the treatment of rare diseases.
Our first-in-class, oral, small molecule therapeutics are antagonists of chemokine receptor CXCR4, which have the potential to treat a broad range of rare diseases, including primary immunodeficiencies (PIs) and cancer. A number of PIs are attributed to the improper trafficking of immune cells related to the CXCR4 receptor and its ligand CXCL12.
X4’s lead product candidate, X4P-001, has completed a Phase 2 trial in patients with a rare genetic PI called Warts, Hypogammaglobulinemia, Infections, and Myelokathexis, or WHIM syndrome. X4 plans to initiate a Phase 3 pivotal trial of X4P-001 in patients with WHIM syndrome. In addition to the initial focus on WHIM syndrome, X4 believes that the biological rationale and available data on X4P-001 support potential therapeutic benefits across a broad range of PIs, including Severe Congenital Neutropenia and certain lymphomas, such as Waldenstrom Macroglobulinemia.
X4 is also developing X4P-002, a CXCR4 antagonist that has unique properties that the company believes will enable penetration of the blood-brain barrier and provide appropriate therapeutic exposures to treat brain cancers, including glioblastoma multiforme (GBM).
X4 is led by a team with experience in research, development and commercialization of therapies to treat rare diseases, and is located in Cambridge, MA.