It would be the first ever late stage clinical trial for the treatment of WHIM syndrome
Reports confirm that X4 Pharmaceuticals Inc. has recently confirmed it has initiated 4WHIM, a pivotal Phase 3 global clinical study of mavorixafor in the treatment of WHIM syndrome, an inherited, rare, primary immunodeficiency disease.
Sources close to the matter informed that the global 4WHIM clinical trial is a randomized, 52-week, placebo-controlled, double-blind, multicentre study designed to assess the efficacy and safety of mavorixafor (X4P-001) in genetically confirmed WHIM patients. This clinical study is formally designed to register up to 28 subjects in around 20 countries which will be followed by an open-label extension trial.
Seemingly, for the trial, the primary efficacy endpoint will compare the level of circulating neutrophils against a clinically meaningful threshold, in response to placebo versus mavorixafor measured during several 24-hour periods through a period of 52 weeks. In addition, secondary endpoints will include wart burden, infection rates, and valuations of immune system function and quality of life.
Sources further stated that mavorixafor is a potentially first-in-class, oral, once-daily, small molecule antagonist of chemokine receptor CXCR4. Supposedly, proof of concept in WHIM patients has been determined with meaningful increases in lymphocyte and neutrophil counts, both vital biomarkers of CXCR4 immune function and signaling. In previous early phase clinical trials, mavorixafor had been well tolerated.
According to Chief Medical Officer of X4 Pharmaceuticals, Lynne Kelley, M.D., the company is ready to initiate the Phase 3 4WHIM clinical trial globally as they seek to confirm transformative potential of mavorixafor as a new therapy for patients with WHIM. For the treatment of WHIM syndrome, this is the first late stage clinical trial ever and starting of this study is a major step in bringing a novel treatment option to an underserved patient population.
For the record, X4 Pharmaceuticals has recently announced a collaboration with Invitae Corporation for supporting confirmation of a WHIM diagnosis, as well as other inherited primary immunodeficiencies.