PD-L1 LEVEL IS UP-REGULATED IN NSCLC CELLS AFTER PEMETREXED TREATMENT

Abstract

Immune checkpoint inhibitors, such as PD-1/PD-L1 targeting monoclonal antibodies, have shown efficacyin the treatment of non-small cell lung cancer (NSCLC) in the adjuvant, first- and subsequent-line settings,in monotherapy or combined to standard chemotherapy regimens in both adeno and squamous histologies.Recent results from KEYNOTE-189 trial indicates that the addition of pembrolizumab to pemetrexed andplatinum-based drug results in longer OS and PFS than chemotherapy alone even in originally PD-L1negative patients with lung adenocarcinoma (Gandhi L. et al. NEJM 2018). Nevertheless, the success of thistherapy is limited and there is an urgent need for developing strategies to sensitize NSCLC to immune-checkpointinhibitors. In this study, we evaluated whether chemotherapeutic agents may alter PD-L1 expression inorder to guide optimal combination/sequencing with Immune checkpoint inhibitors in the clinic.