87PTime-series of peripheral blood biomarkers as biomarkers for immunotherapy in advanced non-small cell lung cancer (aNSCLC) patients

Background: Immune-checkpoint inhibitors (ICIs) as second-line therapy showed an overall survival (OS) benefit, but only 18-20% of aNSCLC patients respond with a median progression-free survival (mPFS) of 2-4 months. The identification of biomarkers to select patients most likely to benefit from ICIs is still an unmet need in clinical practice. Methods: We conducted a retrospective monocentric analysis in 154 aNSCLC patients receiving single-agent nivolumab or pembrolizumab as second-line (68%) and >3rd line (32%) therapy. We recorded complete blood cell count at baseline (T0), before second (T1) and third cycle (T2), assessing neutrophil-lymphocyte ratio (NLR), derived-NLR (dNLR) and lymphocyte-monocyte ratio (LMR). Statistical analyses (univariate and multivariate analysis) were performed to evaluate the correlation between overall response rate (ORR), PFS and OS and the change from baseline of NLR, dNLR and LMR at second (T0-T1) and third cycle (T0-T2). We divided biomarker time-series into two groups of > 30% increase and <30% increase or decrease from baseline value. Results: The only biomarker statistically significantly associated with survival outcomes was NLR. An increase of > 30% of NLR from baseline to the second cycle (NLR T0-T1) was associated with a worse PFS (3.7 vs 4.9 months, HR 1.52 95% CI 1.02 – 2.24; p = 0.04). We also observed a statistically significant correlation between ORR and the >30% increase of LMR from baseline to the second (LMR T0-T1; p < 0.001) and the third cycle (LMR T0-T2; p = 0.001). Conclusions: According to the prognostic value of time-series of biomarkers at second and third cycle from baseline, patients who experienced an increase of > 30% of NLR after the first ICI cycle were associated with a worse PFS; also, an increase of > 30% of LMR after the first and second ICI administration lead to a better ORR. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: D. Galetta: Medical advisor: Bristol-Myers Squibb. All other authors have declared no conflicts of interest.