Real World Data Survival Outcomes of First Line Immunotherapy with Pembrolizumab in High Expressers with stage IV Non-Small Cell Lung Cancer

Abstract

Background. Pembrolizumab monotherapy is standard of care in first line treatment of patients with stage IV lung cancer and programmed death ligand 1 (PD-L1) expression ≥50%. Whether the higher levels of PD-L1 expression predict higher benefit from the treatment with pembrolizumab is still debatable.

Patients and methods. This trial analyzed clinical and pathological characteristics, overall response rate (ORR), and survival outcomes in patients with NSCLC and PD-L1 expression of ≥50% who received front line treatment with pembrolizumab in real world setting. The aim was to evaluate does the level of expression influence survival endpoints.

Results. Fifty-one consecutive patients were evaluated in this study. The median PFS for patients in this study was 12.0 months (95% CI, 7.7–16.2 months), and the median OS was 21.0 months (95% CI, 9.6–32.3 months). Based on PD-L1 status patients were divided into two groups. First one with PD-L1 expression of 50%-79%, and the second with expression over 80% . Gender distribution between the two groups (p=0.029) and difference in stage of the disease (p=0.039) were statistically significant. There was no significant difference in progression free survival (p=0.548) and overall survival (p=0.153) between two groups.

Conclusions. This trial did not confirm relation between higher expression of PD-L1 and better survival outcomes. However, the pitfall of the trial is relatively small number of patients, so with the expansion of this RWD dataset future results might differ.