CTLA4 and neoplasm: While CTLA‐4 expressed on APCs competes with CD28 for binding with B7.1 or B7.2 on T cells, PD‐L1 is predominately upregulated on tumor cells, inhibiting the activation of T cells as such by interacting with PD‐1 expressed on the latter.[75] ICIs targeting PD‐1 include pembrolizumab, nivolumab, spartalizumab, ezabenlimab, or dostarlimab, while atezolizumab, avelumab, or durvalumab target PD‐L1, whereas ipilimumab targets CTLA‐4.