PD-L1 IHC assays applied in clinical trials
| Drug/company | FDA approval | mAb | Platform | Scoring criteria | Positive expression | Comments |
|---|---|---|---|---|---|---|
| Pembrolizumab (Keytruda)/Merck | Approved for NSCLC | 22C3 (DAKO pharmDx) | Link 48 autostainer | ≥50% tumor cellsa | 23% (>50%) 38% (1%-49%) | Companion diagnostic |
| Nivolumab (Opdivo)/ Bristol- Myers Squibb | Approved for squamous and non squamous NSCLC | 28-8 (DAKO pharmDx) | Link 48 autostainer | ≥1% tumor cellsa | SqCC ADC 31% 46% (>10%) 36% 51% (>5%) 53% 69% (>1%) | Complementary diagnosticc |
| Atezolizumab (MPDL3280)/ Roche | Expected in 2016 | SP142 | Information not currently available | Tumor cells and/or tumor infiltrating immune cellsb | IHC3- 6% IHC2/3-37% IHC1/2/3-68% | |
| Durvalumab (MEDI4736)/ Astra Zeneca | Expected in 2016 | SP243 | Information not currently available | ≥25% tumor cellsa | 41% |
a: membranous staining; b: IHC3 [tumor cell (TC)3 or immune cell (IC)3]: PD-L1 expression in >50% of tumor cells or >10% of immune cells, IHC 2/3 (TC2/3 or IC2/3): PD-L1 expression in >5% of tumor cells or immune cells, IHC1/2/3 (TC1/2/3 or IC1/2/3): PD-L1 expression in >1% of tumor cells or immune cells, IHC0 (TC0 and IC0), PD-L1 expression in <1% of tumor cells and <1% of immune cells.c: PD-L1 expression is predictive of response only in non-squamous NSCLC. FDA: the US Food and Drug Administration; SqCC: squamous cell carcinoma; ADC: adenocarcinoma.