NCIt definition : A fixed dose combination of two monoclonal antibodies of which one is directed against
the human negative immunoregulatory checkpoint receptor programmed cell death protein
1 (PD-1; PDCD1; CD279) and the other one is directed against the cytotoxic T-lymphocyte-associated
antigen 4 (CTLA4; CTLA-4), with potential immune checkpoint inhibitory and antineoplastic
activities. Upon administration, anti-CTLA-4/anti-PD-1 monoclonal antibody combination
BCD-217 targets and binds to both PD-1 and CTLA-4 expressed on tumor-infiltrating
lymphocytes (TILs) and inhibits the PD-1- and CTLA-4-mediated downregulation of T-cell
activation and proliferation. This restores immune function and activates a cytotoxic
T-lymphocyte (CTL)-mediated immune response against tumor cells. Both PD-1 and CTLA-4
are selectively expressed on TILs in the tumor microenvironment (TME) and negatively
regulate the activation and effector functions of T-cells. They play key roles in
the downregulation of the immune system and tumor evasion from host immunity. Dual
checkpoint blockade of PD-1 and CTLA-4 enhances T-cell activation and proliferation
more than the blockade of either immune checkpoint receptor alone.;
Semantic type(s)