AR166

AR166 is an investigational multispecific antibody-cytokine fusion protein, referred to as a "Multi-Abkine," developed by Y Biologics for the treatment of solid tumors. The molecule is engineered to simultaneously target the Programmed Cell Death Protein 1 (PD-1) immune checkpoint and the Vascular Endothelial Growth Factor (VEGF), while also incorporating an interleukin-2 variant (IL-2v). This trifunctional approach is designed to overcome the immunosuppressive tumor microenvironment by blocking PD-1/PD-L1 signaling, inhibiting tumor-associated angiogenesis via VEGF neutralization, and promoting the activation and proliferation of effector T cells and natural killer cells through the IL-2v component. AR166 has demonstrated potent anti-tumor activity in preclinical models, including those resistant to standard PD-1 inhibitors, and is currently in Phase 1 clinical development.