Immune Checkpoint Inhibitors Plus Single-Agent Chemotherapy for Advanced Non-Small-Cell Lung Cancer After Resistance to EGFR-TKI

PURPOSE: Platinum-based chemotherapy remains the classic treatment option for patients with advanced non-small-cell lung cancer (NSCLC) who progress while receiving treatment with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs). In this study, we analyzed real-world outcomes of treatment with immune checkpoint inhibitors (ICIs) combined with platinum-free chemotherapy in patients with NSCLC after developing resistance to EGFR-TKIs. METHODS: This retrospective study included patients with mutation-positive NSCLC after developing resistance to EGFR-TKIs. Patients who received chemotherapy alone plus ICIs with or without anti-angiogenic drugs (cohort A) or platinum-based chemotherapy (cohort B) between February 2019 and August 2020 were enrolled. Clinical characteristics, EGFR mutation status, response to therapy, and adverse events (AEs) were retrospectively analyzed. RESULTS: Seventeen patients were eligible and included in the analysis, including 8 in cohort A and 9 in cohort B. After a median follow-up of 7.6 months, the median progression-free survival was 6.5 months [95% confidence interval (CI), 6.1 to 7.0] in cohort A and 3.6 months (95% CI, 1.3–5.8) in cohort B (hazard ratios, 0.22; 95% CI, 0.05–0.93; P = 0.039). The overall response and disease control rates were 50% and 100% in cohort A, and 22% and 89% in cohort B, respectively. Adverse events of grade 3 or higher occurred in 25% of the patients in cohort A and in 33.3% of the patients in cohort B. CONCLUSION: ICIs plus platinum-free, single-agent chemotherapy provides promising progression-free survival and overall response rate benefit, along with a low rate of severe AEs in patients with EGFR-TKI-resistant advanced NSCLC.