VENTANA PD-L1 (SP142), a complimentary diagnostic immunohistochemistry (IHC) assay to ascertain tumor PD-L1 status for patients with metastatic urothelial cancer considering treatment with atezolizuma

摘要

Abstract NCI Protocol: NRG-GY017 “Anti PD-L1 (Atezolizumab) as an Immune Primer and Concurrently with Extended Field Chemoradiotherapy for Node Positive Locally Advanced Cervical Cancer.” Briefly, PD-L1 expression will be assessed using the rabbit anti-human PD-L1 antibody (clone SP142). Using IHC, PD-L1 expression will be scored in tumor cells (as percentage of PD-L1-expressing tumor cells: TC3≥50%, TC2≥5% and <50%, TC1≥1% and <5%, and TC0<1%) and tumor infiltrating immune cells (as percentage of tumor area: IC3≥10%, IC2≥5% and <10%, IC1≥1% and <5%, and IC0<1%). To satisfy the primary objective of the study, the following will be assessed in response to sequential versus concurrent atezolizumab and radiation: (1) peripheral blood T Cell Receptor (TCR) clonality, and (2) peripheral blood expansion of TCR clones, including TCR clones identified in tumor samples. For assessment of the primary endpoint, pre-treatment FFPE tumor biopsies (to determine which TCR clones are present within the tumor), as well as pre-treatment and on-treatment bloods will be required.