Introduction

There is a paucity of data on immune checkpoint inhibitors (ICIs) plus doublet chemotherapy (C) in patients with advanced lung cancer whose tumor harbors an actionable mutation. We sought to provide insight into the role of this combination in relation to chemotherapy alone in this patient population.

Methods

We conducted a retrospective study at the five University of California National Cancer Institute-designated Comprehensive Cancer Centers. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS) and significant adverse events. Adverse events in patients who received a tyrosine kinase inhibitor (TKI) post-ICI were also captured.

Results

A total of 246 patients were identified, 170 treated with C plus ICI and 76 treated with C alone. Driver alterations included EGFR (54.9%), KRAS (32.9%), ALK (5.3%), HER2/ERBB2 (2.9%), ROS1 (1.2%), MET (1.2%), RET (0.8%), and BRAF non-V600 (0.8%). The overall PFS and OS hazard ratios were not significant at 1.12 (95% confidence interval 0.83-1.51; p = 0.472) and 0.86 (95% confidence interval: 0.60-1.24, p = 0.429), respectively. No significant differences in PFS or OS were observed in the mutational subgroups. Grade 3 or greater adverse events were lower in the C plus ICI group. The multivariate analysis for PFS and OS revealed a performance status (Eastern Cooperative Oncology Group) score of 2, and previous TKI treatment was associated with poorer outcomes with C plus ICI.

Conclusions

Our study suggests that patients with oncogenic-driven NSCLC, primarily those with EGFR-driven tumors, treated with a TKI should not subsequently receive C plus ICI. Analysis from prospective clinical trials will provide additional information on the role of ICIs in this group of patients.