X4 Pharmaceuticals, Inc., a clinical-stage biopharmaceutical company, focuses on the research, development, and commercialization of novel therapeutics for the treatment of rear diseases. Its lead product candidate is mavorixafor, an oral small molecule antagonist of chemokine receptor CXCR4, which is in Phase III clinical trial for the treatment of patients with warts, hypogammaglobulinemia, infections, and myelokathexis syndrome; Phase Ib clinical trial to treat severe congenital neutropenia and Waldenström macroglobulinemia; and Phase IIa clinical trial for the treatment of clear cell renal cell carcinoma. The company is also developing X4P-002 for the treatment of glioblastoma multiforme; and X4P-003 to treat patients suffering from chronic rare diseases. X4 Pharmaceuticals, Inc. has a license agreement with Abbisko Therapeutics Co., Ltd. to develop, manufacture, and commercialize mavorixafor in combination with checkpoint inhibitors or other agents in oncology indications. The company was founded in 2014 and is headquartered in Boston, Massachusetts.