XmAb5483

XmAb5483 is a bispecific monoclonal antibody developed by Xencor, designed to target both C-C chemokine receptor type 4 (CCR4) and T-cell immunoreceptor with Ig and ITIM domains (TIGIT). CCR4 is a chemokine receptor predominantly expressed on regulatory T cells (Tregs), which play a critical role in maintaining an immunosuppressive tumor microenvironment. TIGIT is an inhibitory checkpoint receptor found on T cells and natural killer (NK) cells that limits their anti-tumor activity. XmAb5483 utilizes Xencor's proprietary XmAb bispecific Fc domain to facilitate the selective depletion of CCR4-positive Tregs via antibody-dependent cellular cytotoxicity (ADCC) while simultaneously blocking the TIGIT-PVR interaction. This dual approach is intended to reduce immune suppression and enhance effector cell activation, potentially leading to improved clinical outcomes in patients with advanced solid tumors. The drug is currently undergoing Phase 1 clinical evaluation.