5-Year survival in Danish patients with advanced non-small cell lung cancer treated with immune checkpoint inhibitor monotherapy

Abstract

Background Convincing results from randomized controlled trials (RCTs) have led to increasing use of immune checkpoint inhibitors (ICI) as part of standard therapies in real-world (RW) scenarios. However, RW patients differ clinically from RCT populations and might have reduced long-term survival. Currently, only sparse data on 3-5-year survival rate for RW patients with advanced non-small cell lung cancer (NSCLC) treated with ICI exist. Materials and methods A multicenter study was performed including 729 patients with advanced NSCLC receiving monotherapy with ICI (retrospective data (n = 566) and prospective data (n = 163)). Detailed baseline clinical characteristics, programmed death-ligand 1 (PD-L1) tumor proportion score (TPS), and baseline haematological count were registered. Kaplan–Meier estimates and log-rank test were used for survival analyses, Cox regression for determination of prognostic factors. Results Median time of follow-up (FU) was 48.7 months (IQR 37.2–54.3). Median overall survival (OS) in first line treatment was 20.4 months (IQR 8.5–45.0) compared to 11.4 months (IQR 4.6–27.1) in ≥2nd line (HR 1.48, 95% CI 1.25–1.75). Estimated probability of OS was 30% at 3 years, 23% at 4 years, and 13% at 5 years in first line compared to 17, 13, and 11% in ≥2nd line, respectively. For those with performance status (PS) 2, the 2-year OS rate was 32% (95% CI 0.22–0.43) compared to 5% (95% CI 0.01–0.15) in patients with PD-L1 ≥ 50% versus <50%, respectively. Conclusions Compared to RCTs, long-term OS and PFS rates are lower in real-world patients treated with ICI in first line but much improved compared to historic rates on chemotherapy. A promising flattening of both the OS and progression free survival curves illustrates that also a subset of real-world patients obtain long-term remission. Patients with PS 2 and PD-L1 ≥ 50% may obtain clinically meaningful 2-year PFS and OS rates.