Table 1. PD-1 and PD-L1 inhibitors in non-small cell lung cancer.

PD-1/PD-L1 inhibitors	Assay, antibody	Cell type	Current PD-L1 IHC testing
Nivolumab (α-PD-1)	Dako 28-8	Tumour cells	Optional for 2nd line
Pembrolizumab (α-PD-1)	Dako 22C3	Tumour cells	Mandatory for 1st and 2nd line
Atezolizumab (α-PD-L1)	Ventana SP142	Tumour cells; immune cells	Optional for 2nd line
Durvalumab (α-PD-L1)	Ventana SP263	Tumour cells	Not yet approved
Avelumab (α-PD-L1)	Dako 73-10	Tumour cells	Not yet approved

Five inhibitors have been investigated, each in combination with a different PD-L1 immunohistochemistry assay (Column ‘Assay’) that includes a different primary antibody. Scoring includes either tumour cell or tumour cells and immune cells (Column ‘Cell Type’). Three inhibitors have been approved, one with mandatory PD-L1 IHC and two with optional PD-L1 IHC (Column ‘Current PD-L1 IHC testing’). Two more inhibitors are in advanced clinical trials but have not achieved approval yet.