PD-1 / VEGF / TGF-β receptor II (TGFβRII)

Class

Trispecific antibody (checkpoint blockade + anti-angiogenic + TGF-β trap)

Pathway

PD-1 immune checkpoint, VEGF angiogenesis, TGF-β immunosuppression

This molecule is a multispecific antibody engineered to act on three distinct biological pathways simultaneously: the PD-1 immune checkpoint, the VEGF angiogenesis pathway, and TGF-β immunosuppressive signaling. PD-1 is a receptor on T cells that, when engaged, dampens their ability to attack tumor cells; blocking it restores T-cell activity. VEGF drives formation of new blood vessels that supply tumors with nutrients and can also shape an immunosuppressive tumor environment; neutralizing it starves tumor vasculature and can improve immune cell entry into tumors. TGF-β is a signaling protein that suppresses effector T-cell function and promotes tissue remodeling that excludes immune cells from tumors; trapping it via its receptor removes this brake. The rationale for combining all three activities in a single molecule is that tumors resistant to checkpoint blockade alone often owe that resistance to VEGF- and TGF-β-driven immune exclusion, so addressing all three pathways at once may convert poorly infiltrated,