Lemzoparlimab (also known as TJC4) is an investigational, humanized monoclonal antibody designed to selectively target CD47, a cell-surface protein often overexpressed by cancer cells as a "don't eat me" signal. Unlike earlier anti-CD47 antibodies, lemzoparlimab is engineered with a differentiated binding epitope to minimize red blood cell (RBC) binding and agglutination, thereby reducing the hematologic toxicity commonly associated with CD47 blockade. By blocking the interaction between CD47 and its receptor SIRPα on macrophages, it aims to promote the phagocytosis and elimination of tumor cells. It is being developed primarily for the treatment of hematologic malignancies and solid tumors, both as monotherapy and in combination regimens.