Efficacy and safety of different PD-1 inhibitors as first-line treatment for advanced or metastatic squamous non-small cell lung cancer: A retrospective real-world study

Background The efficacy and safety of combining chemotherapy with different anti-PD-1 treatment as first-line treatment in advanced or metastatic squamous non-small-cell lung cancer (NSCLC) in a real-world study remains unknown. Therefore, this real-world study investigated the efficacy and safety of different PD-1 inhibitors as first-line treatment for advanced or metastatic squamous NSCLC. Methods Patients (n = 239) with advanced or metastatic squamous NSCLC without driver-gene mutations treated with immune checkpoint inhibitors (ICIs) as first-line treatment were retrospectively identified between October 2018 and December 2021. Results The objective response rate (ORR) and disease control rate (DCR) were 48.1% and 87.4%, respectively. The median overall survival (OS) and progression-free survival (PFS) were 26.0 and 10.0 months, respectively. The ORR in the pembrolizumab, sintilimab, camrelizumab, tislelizumab, and toripalimab groups was 52.5%, 44.7%, 50.0%, 40.3%, and 66.7%, respectively. The PFS in the pembrolizumab, sintilimab, camrelizumab, tislelizumab, and toripalimab groups was 11.5, 10.0, 8.5, 10.0, and 9.0 months, respectively (P = 0.329). The OS in the pembrolizumab, camrelizumab, and toripalimab groups was 26.0, 22.0, and 19.0 months, respectively (P = 0.967). Overall, 36.0% of patients experienced immune-related adverse events (irAEs; 12.6% of these were grade 3 or 4). The most common irAEs were nephritis (10.0%, 24/239), pneumonitis (8.8%, 21/239), and liver insufficiency (8.8%, 21/239). Patients with high baseline IL-6 levels had a significantly shorter OS than their counterparts (P = 0.021). Conclusion ICI treatment is a safe and effective first-line therapy in advanced or metastatic squamous NSCLC. Baseline serum IL-6 levels may predict treatment efficacy and survival benefit in NSCLC treated with PD-1 inhibitors.