This immune checkpoint pathway is the target of anti-PD-1 monoclonal antibodies (i.e., pembrolizumab, retifanlimab, nivolumab) and anti-PD-L1 antibodies (i.e., avelumab), which prevent PD-L1, found on tumor cells, from binding PD-1, thereby enabling T cell activation (Figure 2B,C). The gene discussed is CD274; the disease is neoplasm.