Definition

A bifunctional fusion protein directed against both human programmed death ligand 1 (PD-L1) and transforming growth factor beta (TGF-beta), with potential antineoplastic and immune checkpoint modulating activities. Upon administration, anti-PD-L1/anti-TGF-beta bifunctional fusion protein TQB2858 targets, binds to and neutralizes TGF-beta on tumor cells and simultaneously targets, binds to, and inhibits the activity of PD-L1 on the tumor cells. This prevents both TGF-beta- and PD-L1-mediated immunosuppressive pathways signaling, and increases natural killer (NK) cell and cytotoxic T-lymphocyte (CTL) activities. This also restores and enhances anti-tumor responses and inhibits tumor cell proliferation in susceptible tumor cells. TGF-beta and PD-L1 are both upregulated in certain types of cancers; their overexpression is associated with increased evasion of immune surveillance and contributes to poor prognosis.