Circulating biomarkers and outcomes in advanced non-small cell lung cancer patients treated with anti-PD1 (program death 1 receptor) monoclonal antibodies.

Abstract

e20592 Background: Current evaluation of immunohistochemical expression of PDL-1 (program death receptor 1 ligand) can select some non-small cell lung cancer (NSCLC) patients who may benefit from anti-PD1 directed therapy. It is an imperfect marker and there is little information about systemic modulation of the immune system on therapy. In this study we explored the prognostic value of baseline circulating immune checkpoint and inflammatory molecules in advanced non-small cell lung cancer (NSCLC) patients receiving anti-PD1 therapy. Methods: Prospectively collected serum from advanced NSCLC patients receiving nivolumab or pembrolizumab were evaluated with the MILLIPLEX Human High Sensitivity T-cell (17-plex) and ProcartaPlex Human Immuno-Oncology Checkpoint (14-plex) panels on our Luminex FlexMAP 3D. Biomarker level cutoffs were optimized and evaluated against progression-free survival (PFS) and overall survival (OS) using log-rank analysis. Results: 21 cases were enrolled in this pilot study: 72% Caucasian, 61% female, 24% never-smokers. IL-10 was found to have a significant association with both PFS (p = 0.0055) and OS (p = 0.024), with levels below 3.32 pg/mL being associated with a superior clinical outcome. We also found IL-2 and IL-6 to have significant associations with PFS (p = 0.033 and 0.040, respectively), again, with low levels being associated with a superior outcome. Neither of these had significant associations with OS. Low circulating levels of the T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) protein were associated with superior PFS (p = 0.036), and a weak trend (p = 0.19) for OS. Conclusions: In this small exploratory pilot study we identified several circulating molecules associated with inflammation and immune system regulation that may have prognostic value for anti-PD-1 therapy. Notably, TIM-3 is a Th1-specific protein associated with macrophage activation and is also a component of T-cell exhaustion along with LAG3 and PD-1. Additional studies to follow up on these findings in larger cohorts are underway.