Table 1. PD-L1 testing methods.

PD-L1 antibody	Platform	Detection system	Agent	Cut-off
PD-L1 antibody	Platform	Detection system	Agent	NSCLC	HNSCC	UC
SP263	Ventana BenchMark Ultra^a	OptiView DAB IHC Detection Kit^a	Durvalumab^b	TC: ≥25%	TC: ≥25%	TC or IC: ≥25%
22C3	Dako Autostainer Link 48^c	EnVision FLEX visualization system^c	Pembrolizumab^d	TC: ≥1%, ≥50% TPS	TC or IC: >1%, >50%	TC and IC: ≥10% TPS
28-8	Dako Autostainer Link 48	EnVision FLEX visualization system	Nivolumab^e	TC: >1%, >5%	>1%, >5%	TC: >1%, >5%
SP142	Ventana BenchMark Ultra	OptiView DAB IHC Detection Kit and OptiView Amplification Kit^a	Atezolizumab^f	TC: ≥10%, IC: ≥50%	TC: ≥5%, IC: ≥5%	IC: ≥5%
73-10	Dako Autostainer Link 48	EnVision FLEX visualization system	Avelumab^d,^g	TC: ≥1%, 50%, 80%	NA	TC: ≥5%

^a, Ventana Medical Systems, Tucson, AZ, USA; ^b, Agilent Technologies, Mississauga, ON; ^c, AstraZeneca, Cambridge, UK; ^d, Merck, Kenilworth, NJ, USA; ^e, Bristol-Myers Squibb, New York, NY, USA; ^f, Roche, Basel, Switzerland; ^g, Pfizer, New York, NY, USA. NSCLC, non-small cell lung cancer; HNSCC, head-and-neck squamous cell carcinoma; UC, urothelial carcinoma; IHC, immunohistochemistry; TC, tumour cell; IC, immune cell; TPS, tumour proportion score (PD-L1-expressing TCs and infiltrating ICs relative to the total number of TCs); NA, not applicable.