Table 1 PD-L1 assay characteristics and performance in NSCLC
Assay | Antibody | FDA-approved Indication in NSCLC | Cutoff Value | Performancea |
|---|---|---|---|---|
22C3 IHC pharmDx | Monoclonal mouse anti-PD-L1, Clone 223 | Approved as a companion diagnostic to select patients with advanced NSCLC for treatment with pembrolizumab first-line (TPS ≥ 50%) or after progression on a platinum containing chemotherapy regimen (TPS ≥ 1%) | • TPS < 1% PD-L1 negative • TPS 1–49% PD-L1 positive • TPS ≥ 50% High PD-L1 expression | Found to be closely aligned with 28–8 and SP263 IHC assays |
28–8 IHC pharmDx | Monoclonal Rabbit anti-PD-L1, Clone 28–8 | Approved as a complementary diagnostic to aid in non-squamous NSCLC patient selection for treatment with nivolumab | Qualitative test reported as a percentage of tumor cells exhibiting positive membrane staining | Found to be closely aligned with 22C3 and SP263 IHC assays |
PD-L1 (SP142) Assay | Monoclonal Rabbit anti-PD-L1, Clone SP142 | Approved as a complementary diagnostic to aid in NSCLC patient selection for treatment with atezolizumab | PD-L1 expression in ≥ 50% tumor cells or ≥ 10% immune-infiltrating cells is associated with enhanced survival | Consistently stained fewer PD-L1 tumor cells |
PD-L1 (SP263) Assay | Monoclonal Rabbit anti-PD-L1, Clone SP263 | CE mark only, not approved by the FDA for patients with NSCLC | The CE mark was granted and expanded based on demonstrated equivalency to the 28–8 and the 22C3 IHC assays | Found to be closely aligned with 22C3 and 28–8 IHC assays |