Pembrolizumab for Previously Treated, PD-L1-expressing Advanced NSCLC: Real-world Time on Treatment and Overall Survival

Abstract

Background: Immune checkpoint inhibitors have been rapidly adopted for therapy of advanced non-small-cell lung cancer (aNSCLC) based on clinical trial findings. Our aim was to examine outcomes in United States oncology practice settings for patients prescribed pembrolizumab monotherapy for previously treated, programmed death ligand-1 (PD-L1)-expressing aNSCLC, thus clinically similar to patients in the KEYNOTE-010 trial.

Patients and methods: This retrospective observational study used a nationally representative database to identify adult patients with histologically confirmed aNSCLC and PD-L1 tumor proportion score (TPS) ≥ 1% previously treated with platinum-containing chemotherapy (and appropriate tyrosine kinase inhibitor if nonsquamous aNSCLC with EGFR/ALK genomic tumor aberration). Eligible patients initiated pembrolizumab monotherapy from January 1, 2016, to November 29, 2018; data cutoff was May 31, 2019. The Kaplan-Meier method was used to estimate real-world time on treatment (rwToT) and overall survival (OS).

Results: The 349 eligible patients included 199 (57%) men; the median age was 68 years (range, 37-84 years); 70 (25%) of 278 patients with known performance status had Eastern Cooperative Oncology Group score ≥ 2. The median patient follow-up was 8.1 months (range, 1 day to 39.2 months). The median rwToT was 4.9 months (95% confidence interval [CI], 3.7-5.8 months) overall and 5.8 months (95% CI, 4.2-6.6 months) for the TPS ≥ 50% cohort (n = 218). The median OS was 13.8 months (95% CI, 11.0-16.5 months) and 16.5 months (95% CI, 13.7-22.0 months) overall and for TPS ≥ 50%, respectively; 12-month survival rates were 54% and 60%, respectively.

Conclusion: Patients treated at oncology practices with pembrolizumab monotherapy for previously treated PD-L1-expressing aNSCLC experienced rwToT and OS similar to treatment duration and OS in phase III clinical trial settings.

Keywords: Antineoplastic agents; Comparative effectiveness research; Non-small cell lung carcinoma; Programmed cell death 1 ligand; Survival analysis.