Real-world outcomes of atezolizumab in pretreated patients with metastatic non-small cell lung cancer

Immunotherapy is a highly effective second-line option for advanced NSCLC. Long-term outcomes of two randomized phase 2 POPLAR and phase 3 OAK studies revealed a survival benefit with atezolizumab in patients with previously treated NSCLC regardless of the level of PD-L1 expression or histology. Objective. To evaluate the real-world effectiveness and safety of atezolizumab in previously treated patients with metastatic NSCLC. Material and methods. This single-site retrospective study included previously treated patients with metastatic NSCLC who received atezolizumab between 2019 and 2023 in the N. N. Blokhin National Research Medical Center of Oncology. Primary endpoints were real-world progression-free survival (PFS) and overall survival (OS) rates. Results. 62 patients were included in the study. The median follow-up time was 53.55 months. The median PFS and OS for the patients receiving atezolizumab were 6.9 months (95% CI 1.69—12.1) and 16.4 months (95% CI 10.99—21.8), respectively. The 5-year PFS and OS rates were 5.3% and 21.2%, respectively. Multivariate analysis identified clinical trials ineligibility (ECOG performance status 2—3, comorbidities, acute infection, corticosteroids) and CNS metastasis as significant independent negative predictors of overall survival (HR=2.11, p=0.021 and HR=2.41, p=0.016, respectively). 4 (6.4%) patients had immune-related adverse events (irAE) grade 3—4. The median time to irAE any grade from the start of atezolizumab was 9.5 (min—max: 1—52) months. Conclusion. The patients without CNS metastasis and eligible to clinical trials had better real-world five-year outcomes of atezolizumab in second+ line treatment.