VivoGenie Anti-Human PD-1 (Spartalizumab) Biosimilar (IVMB0537)

PD-1 is a transmembrane protein in the CD28/CTLA-4 subfamily of the Ig superfamily ^{1, 2} . When stimulated via the T cell receptor (TCR), Tregs translocate PD-1 to the cell surface ³. Programmed cell death 1 ligand 1 (PD-L1; CD274; B7H1) and programmed cell death 1 ligand 2 (PD-L2; CD273; B7DC) have been identified as PD-1 ligands ¹. PD-1 is co-expressed with PD-L1 on tumor cells and tumor-infiltrating antigen-presenting cells (APCs) ² . Additionally, PD-1 is co-expressed with IL2RA on activated CD4 + T cells ³ .

PD-1 is an immune checkpoint receptor that suppresses cancer-specific immune responses ⁴. Additionally, PD-1 acts as a T cell inhibitory receptor and plays a critical role in peripheral tolerance induction and autoimmune disease prevention as well as important roles in the survival of dendritic cells, macrophage phagocytosis, and tumor cell glycolysis ². PD-1 prevents uncontrolled T cell activity, leading to attenuation of T cell proliferation, cytokine production, and cytolytic activities. Additionally, the PD-1 pathway is a major mechanism of tumor immune evasion, and, as such, PD-1 is a target of cancer immunotherapy ².

Spartalizumab is a humanized IgG4 anti-PD1 antibody that has been tested for thetreatment of various cancers ^{5, 6}. Spartalizumab binds PD-1 with sub-nanomolar affinity and blocks interactions with ligands PD-L1 and PD-L2, leading to T cell activation ⁵.