A humanized monoclonal antibody directed against CD117 (tyrosine-protein kinase KIT; c-Kit; mast/stem cell growth factor receptor; SCFR), that can potentially be used to deplete hematopoietic stem cells (HSCs). Upon administration, briquilimab targets and binds to CD117. This prevents the binding of stem cell factor (SCF) to its receptor CD117 on HSCs. As CD117 binding to SCF is critical for survival and maintenance of blood forming stem cells, blocking this interaction causes the HSCs that are present in the bone marrow niches to be depleted. Briquilimab can potentially be used as a conditioning regimen to prepare patients for hematopoietic stem cell transplantation.