Immunology

Shaperon is developing Papiliximab, a single-domain bispecific antibody targeting PD-L1 and CD47, designed for patients who are unresponsive to conventional PD-L1 immune checkpoint inhibitors.

Papiliximab is a CD47/PD-L1 bispecific single-domain antibody that blocks both the PD-1/PD-L1 and CD47/SIRP-α immune checkpoint pathways.

According to in vitro evaluations, Papiliximab effectively inhibits PD-1/PD-L1 binding and activates CD4+ T lymphocytes. It also efficiently blocks the CD47/SIRP-α interaction and promotes macrophage-mediated phagocytosis of CD47-expressing tumor cells. As a result, it exhibits stronger anti-tumor activity than conventional PD-L1 antibodies.

Papiliximab is a humanized IgG4-type CD47/PD-L1 single-domain bispecific antibody, engineered to maximize efficacy (tumor phagocytosis) while minimizing red blood cell agglutination.