Long-term real-world outcomes of first-line immunotherapy in non-small cell lung cancer – a population-based cohort study in Sweden

Background: In a previous study, we explored real-world programmed death-ligand 1 (PD-L1) testing and treatment patterns for patients with advanced non-small cell lung cancer (NSCLC) in the era of immune-oncology. The present study aimed to investigate overall survival (OS) with PD-(L)1 inhibitors with longer-term follow-up in the Swedish setting. Materials and methods: Data were extracted from the Swedish National Lung Cancer Registry for patients with NSCLC stage IIIB-IV and ECOG performance status (PS) 0–2 who initiated first-line systemic treatment from 1-April-2017 to 30-June-2021 with data cut-off 30-June-2022. OS and Kaplan–Meier estimates were calculated from start of the PD-(L)1 inhibitor therapy, with subgroups based on nonsquamous/squamous (NSQ/SQ) histology, and further by PS, and PD-L1 status (available from 1-January-2018) provided sufficient sample size. Results: We identified 784 (NSQ:590/SQ:194) patients treated with first-line PD-(L)1 inhibitor monotherapy and 369 (NSQ:305/SQ:64) patients receiving combination regimens. Median OS (95% confidence interval [CI]) was 15.2 (12.4–17.7) and 12.9 (10.6–15.8) months with monotherapy and 17.0 (13.6–23.9) and 18.0 (13.9-NA) months with combination regimens for NSQ/SQ patients. In PS2, median OS with monotherapy was 5.0 (3.7–7.1) and 8.9 (6.2–12.9) months for NSQ/SQ patients (n = 138/59), 5.3 (3.6–13.4) months with combination regimens in NSQ (n = 58) and not evaluable in SQ patients. For PS0-1 patients with tumor cell PD-L1 expression ≥50%, the median OS for NSQ was 23.8 (17.7–29.3) and 27.3 (21.6-NA) months for monotherapy/combination therapy (n = 281/55), while the median OS for combination regimens for PD-L1 <1% and 1–49% was 18.6 (12.1–26.9) and 15.9 (10.8–26.7) months (NSQ; n = 65/87). Interpretation: Real-world OS in Swedish patients receiving first-line PD-(L)1 inhibitor-based regimens was consistent with that observed in clinical trials. Moderate OS rates were observed in PS2, with limited sample sizes. Further research is needed in these patients, as well as in high PD-L1, given the slightly longer OS for combination therapy compared to monotherapy seen for NSQ.