Summary of assays and response rates in immune checkpoint inhibitor trials in metastatic renal cell carcinoma
| Ref | CPI | Drug | Target | Antibody for PD-L1 IHC Assay | Definition of PD-L1 positivity | ORR (PD-L1+) | ORR (PD-L1-) | ORR All Patients |
|---|---|---|---|---|---|---|---|---|
| [14] | Single Agent | Nivolumab | PD-1 | Rabbit 28–8 (Dako) | PD-L1 ≥ 5% (TC) | 45% (13/29) | 18% (14/78) | 25% (27/107) |
| [18] | Single Agent | Atezolizumab | PD-L1 | Rabbit SP142 (Ventana) | IHC 1/2/3 ICa | 18% (6/33) | 9% (2/22) | 15% (8/55) |
| [25] | Combinationb | Nivolumab and Ipilimumab | PD-1 and CTLA-4 | Rabbit 28–8 (Dako) | PD-L1 ≥ 1% (TC) | 58% (58/100) | 37% (105/284) | 42% (163/384) |
TC tumor cells, IC percentage of PD-L1 positive immune cells in the tumor microenvironment, ORR overall response rate
aIHC 1 is ≥1%, IHC 2 is ≥5%, IHC 3 is ≥10%
bIMDC Intermediate/poor risk