Efficacy and Safety Evaluation of Immune Checkpoint Inhibitors in Combination With Chemotherapy for Extensive Small Cell Lung Cancer: Real-World Evidence

Abstract

Introduction: Extensive small cell lung cancer (ES-SCLC) are currently managed using first-line chemotherapy options, including atezolizumab (Atezo) plus etoposide and carboplatin (CE) or durvalumab (Durva) plus etoposide with either cisplatin (PE) or carboplatin (CE). However, a definitive distinction in therapeutic effects between Atezo and Durva in these regimens remains unestablished.

Methods: We analyzed data from 100 patients diagnosed with ES-SCLC who received immune checkpoint inhibitors (ICIs) as first-line chemotherapy. Among them, 70 were administered Atezo + CE, 12 received Durva + PE, and 18 received Durva + CE. We assessed the efficacy of the two ICIs across various factors.

Results: The progression-free survival (PFS) and overall survival (OS) did not significantly differ between Atezo + CE and Durva + CE/PE as first-line chemotherapy treatments for SCLC. We observed no significant differences in age, sex, performance status (PS), liver metastasis, bone metastasis, or platinum-based agent usage between the treatment cohorts. However, a marked improvement in PFS and OS was observed in the solitary patient with brain metastasis treated with Atezo + CE.

Conclusion: The primary distinction between these treatments was observed in the management of patients with brain metastasis. The literature lacks comparative studies on the effects of first-line ICI treatment on the central nervous system, rendering our findings significant in clinical practice. Despite the retrospective nature of this study and the potential for various biases, we recommend the preferential use of Atezo + CE in patients with brain metastasis to potentially enhance prognosis.

Keywords: atezolizumab; durvalumab; extensive‐stage small cell lung cancer; first‐line treatment; immune checkpoint blockade; real‐world evidence.