BGB-A333 + tislelizumab

BGB-A333 + tislelizumab is an investigational combination of two immune checkpoint inhibitor monoclonal antibodies: BGB-A333, a humanized IgG1 monoclonal antibody that targets programmed death-ligand 1 (PD-L1), and tislelizumab, a humanized IgG4 monoclonal antibody that targets programmed cell death protein-1 (PD-1)[1][2][3]. BGB-A333 inhibits PD-L1, thereby blocking its interactions with PD-1 and CD80 (B7-1), releasing inhibitory signals on T cells and enhancing T-cell expansion and antitumor immunity. Tislelizumab blocks PD-1, preventing immune evasion by tumors through reactivation of T cells. The rationale for combining these agents is potential synergistic immunomodulatory effects when both PD-1 and PD-L1 signaling pathways are inhibited in the tumor microenvironment[2][3]. This combination is primarily being developed for the treatment of advanced solid tumors, including but not limited to non-small cell lung cancer and urothelial carcinoma[3].