LILRB4-PROTAC

LILRB4-PROTAC is an experimental proteolysis-targeting chimera (PROTAC) designed to induce the degradation of Leukocyte Immunoglobulin-Like Receptor B4 (LILRB4). LILRB4 is an inhibitory receptor that is aberrantly expressed in multiple myeloma (MM) cells and plays a critical role in establishing a tumor-driven immunosuppressive microenvironment. It promotes the accumulation of myeloid-derived suppressor cells (MDSCs) and erythroid-derived myeloid cells (EDMCs) via the S100A4-CCL3 signaling axis, which in turn impairs T-cell-mediated anti-tumor immunity. By degrading LILRB4, this agent aims to disrupt this inflammatory circuit, restore anti-tumor immunity, and reduce tumor burden. Preclinical studies in murine models of multiple myeloma have demonstrated that LILRB4-PROTAC treatment significantly reduces tumor growth and reprograms the myeloid microenvironment.