Table 1.

IHC PD-L1 assay comparison

Assay Antibodies PD-L1 clone	Staining platform	FDA designed	Immunotherapy drug	PD-L1 binding domain	Clinical cutoff(s) for PD-L1 expression
28-8	Dako Link 48	Complementary diagnostic	Nivolumab	Tumor cells	≥ 1%, ≥ 5%
22C3	Dako Link 48	Companion	Pembrolizumab	Tumor cells	≥ 1%, ≥ 50%
SP142	Ventana Benchmark or Ultra	Complementary diagnostic	Atezolizumab	Tumor cells and/or	≥ 1%, ≥ 5%, ≥ 50%
				Infiltrating immune cells	≥ 1%, ≥ 5%, ≥ 10%
SP263	Ventana Benchmark or Ultra	No designed	Durvalumab	Tumor cells	≥ 25%
73-10	Dako Link 48	Under development	Avelumab	Tumor cells	≥ 1%, ≥ 5%, ≥ 80%

Clinical cutoff(s) for PD-L1 expression of five-assay comparison