First-line pembrolizumab with or without platinum doublet chemotherapy in non-small-cell lung cancer patients with PD-L1 expression ≥50%

Pembrolizumab plus chemotherapy is currently used in the first-line treatment of advanced non-small-cell lung cancer without EGFR mutations or ALK rearrangements, regardless of PD-L1 expression status. A study comparing chemotherapy plus pembrolizumab versus pembrolizumab alone has never been performed in patients with PD-L1 ≥50%. The aim of this trial is to perform such a comparison as first-line treatment in patients not eligible for locally advanced treatment who have expression of PD-L1 on ≥50% of tumor cells. The expected results are a reduction in the risk of early progression. A higher objective tumor response is also expected with the combination of chemotherapy and pembrolizumab compared with pembrolizumab alone. The study will allow a direct comparison of the proportion of patients who derive long-term benefit from the treatment. Clinical trial number: EudraCT (2020-002626-86); ClinicalTrials.gov (NCT04547504). Lay abstract Non-small-cell lung cancer (NSCLC) is the most frequent type of lung cancer. Most NSCLC patients are diagnosed with advanced disease and only 10-15% of them are alive after 5 years. In the absence of specific tumor mutations, the currently recommended treatment is a combination of chemotherapy and immunotherapy with the monoclonal antibody pembrolizumab. The goal of immunotherapy is to prevent cancer from evading the immune system by interacting with molecules expressed at the surface of tumor cells (PD-L1) or immune cells (PD-1). A study comparing chemotherapy plus pembrolizumab versus pembrolizumab alone has never been performed in patients with a high level of PD-L1 expression on tumor cells. Therefore we designed the PERSEE study to compare these treatments in advanced-stage NSCLC patients with PD-L1 expression on ≥50% of tumor cells.