Definition

A bispecific antibody targeting both the human negative immunoregulatory checkpoint receptor programmed cell death protein 1 (PD-1; PDCD1; CD279) and the T-cell surface antigen CD3, with potential immunomodulatory and antineoplastic activities. Upon administration, anti-PD-1/anti-CD3 bispecific antibody ONO-4685 binds to both PD-1 expressed on activated T and B cells and certain malignant T cells and CD3 antigen on cytotoxic T lymphocytes (CTLs). This may activate and redirect CTLs to PD-1-expressing cells, resulting in CTL-mediated killing of these cells. This may lead to anti-tumor activity in some T-cell lymphomas, and immunomodulatory activity in some autoimmune diseases.