X4 Pharmaceuticals
The purpose of this study is to demonstrate the efficacy and evaluate the safety and tolerability of mavorixafor in participants with congenital or acquired primary autoimmune and idiopathic chronic neutropenic disorders who are experiencing recurrent and/or serious infections as assessed by demonstrating its clinical benefit and increasing levels of circulating neutrophils.
All participants will continue their pre-study background therapy, defined as the participant's current treatment regimen. Options include, but are not limited to, granulocyte-colony stimulating factor (G-CSF), immunoglobulin replacement therapy, prophylactic antibiotics, or "watchful waiting".
Key Inclusion Criteria: * Diagnosis of congenital or acquired primary autoimmune and idiopathic chronic neutropenic disorder ≥6 months prior to the screening visit that is not attributable to medications, active or recent infections or malignancy. * Congenital Neutropenia, including but not limited to these classifications: 1. Isolated with a permanent (non-cyclic) presentation, for example, elastase, neutrophil expressed (ELANE), colony stimulating factor 3 receptor (CSF3R), C-X-C chemokine receptor 2 (CXCR2), Wiskott-Aldrich syndrome (WAS) 2. Associated with extra-hematologic manifesta…
Mavorixafor will be administered per schedule specified in the arm description.
Placebo will be administered per schedule specified in the arm description.