Real-World Treatments and Clinical Outcomes in Advanced NSCLC without Actionable Mutations after Introduction of Immunotherapy in Japan

Abstract

The aims of this study were to describe systemic treatment patterns and clinical outcomes for unresectable advanced/metastatic non-small-cell lung cancer (NSCLC) by first-line regimen type in real-world clinical settings in Japan after the introduction of first-line immune checkpoint inhibitor (ICI) monotherapy in 2017. Using retrospective chart review at 23 study sites, we identified patients ≥20 years old initiating first-line systemic therapy from 1 July 2017 to 20 December 2018, for unresectable stage IIIB/C or IV NSCLC; the data cutoff was 30 September 2019. Eligible patients had recorded programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) and no known actionable EGFR/ALK/ROS1/BRAF genomic alteration. Kaplan-Meier method was used to determine time-to-event endpoints. Of 1208 patients, 647 patients (54%) received platinum doublet, 463 (38%) received ICI monotherapy, and 98 (8%) received nonplatinum cytotoxic regimen as first-line therapy. PD-L1 TPS was ≥50%, 1−49% and <1% for 44%, 30%, and 25% of patients, respectively. Most patients with PD-L1 TPS ≥50% received ICI monotherapy (453/529; 86%). Excluding 26 patients with ECOG performance status of 3−4 from outcome analyses, the median patient follow-up was 11.3 months. With first-line platinum doublet, ICI monotherapy, and nonplatinum cytotoxic regimens, median overall survival (OS) was 16.3 months (95% CI, 14.0−20.1 months), not reached, and 14.4 months (95% CI, 10.3−21.2 months), respectively; 24-month OS was 40%, 58%, and 31%, respectively. Differences in OS relative to historical cohort data reported in Japan are consistent with improvement over time in real-world clinical outcomes for advanced NSCLC.

Keywords: chemotherapy; immune checkpoint inhibitor; non-small-cell lung cancer; nonplatinum therapy; overall survival.

Figure 1

Overall survival by tumor histology among patients who received first-line therapy (A) overall and with (B) platinum doublet, (C) ICI monotherapy, and (D) nonplatinum cytotoxic regimen.

Figure 2

Overall survival by age group among patients who received first-line therapy (A) overall and with (B) platinum doublet, (C) ICI monotherapy, and (D) nonplatinum cytotoxic regimen.