Felzartamab is a human IgG1 monoclonal antibody targeting CD38. It binds CD38 and depletes CD38-positive cells via Fc-mediated effector functions (ADCC, ADCP, and possibly complement). In this study, two formulations (T by I-Mab Biopharma and R by Patheon Italia) of the same drug were compared after a single 8 mg/kg IV dose for PK, safety, tolerability, and immunogenicity.