Peripheral myeloid cells as prognostic markers in patients (pts) with non-small cell lung cancer (NSCLC) treated with cemiplimab: Pooled analysis of EMPOWER-Lung 1 and EMPOWER-Lung 3 phase 3 trials.

Abstract

9028 Background: Circulating innate and adaptive immune cells can modulate clinical responses to immune checkpoint inhibition in pts with cancer; however, there are no clear validated baseline clinical tests to guide clinicians, outside of programmed cell death-ligand 1 (PD-L1) IHC tests on limited biopsy specimens. High neutrophil/lymphocyte ratio (NLR) is associated with poor prognosis in NSCLC, but data are limited on the potential contribution of other immune cells such as monocytes and eosinophils in modulating systemic immune response. Further, previous correlative studies have not established clinically actionable immune cell cut-off values. Methods: We used multiple quantitative analytic methods including multivariable Cox regression and conditional decision trees to assess the prognostic importance of NLR and peripheral myeloid cells, including monocytes and eosinophils, in pts with NSCLC treated with cemiplimab in Phase 3 trials EMPOWER-Lung 1 (NCT03088540) and EMPOWER-Lung 3 (NCT03409614). In EMPOWER-Lung 1, pts with PD-L1 ≥50% were randomized 1:1 to cemiplimab 350 mg every 3 weeks (Q3W) or platinum-based chemotherapy (chemo). EMPOWER-Lung 3 was a 2-part study. In Part 1, pts with PD-L1 < 50% were randomized 1:1:1 to chemo, cemiplimab 350 mg Q3W + chemo, or cemiplimab 350 mg Q3W + ipilimumab 50 mg Q6W + chemo. In Part 2, pts were randomized 2:1 to receive cemiplimab 350 mg or placebo Q3W + chemo. Results: Overall, 691 pts in EMPOWER-Lung 1 and 769 pts in EMPOWER-Lung 3 were included in this analysis. The results showed significant association between multiple factors including NLR and overall survival (OS) and progression-free survival (PFS). For pts with NLR > 3.98 vs ≤3.98, median OS (95% CI) was 10 (9–13) vs 20 (17–24) months (HR: 2.04; 95% CI: 1.60–2.61; P< 0.001) and median PFS (95% CI) was 4 (4–6) vs 6 (6–7) months (HR: 1.80; 95% CI: 1.50–2.18; P< 0.001), respectively, accounting for known prognostic factors. In multivariable analyses, monocytes (OS HR: 1.72; 95% CI: 1.29–2.30; P< 0.001; PFS HR: 1.37; 95% CI: 1.08–1.75; P= 0.010) and log eosinophils (OS HR: 0.90; 95% CI: 0.85–0.97; P= 0.003; PFS HR: 0.93; 95% CI: 0.88–0.98; P= 0.004) were significantly associated with OS and PFS in both studies. (Neutrophil + monocyte)/lymphocyte ratio was the top predictor of both OS and PFS in decision tree analysis. Peripheral blood cell count correlations were not affected by tumor PD-L1 levels (ρ < 0.15 for all markers). Conclusions: This is a large and comprehensive prognostic analysis of data from two prospective Phase 3 clinical trials in advanced NSCLC. Clinically actionable peripheral blood cell count parameters, incorporating putative immunosuppressive myeloid cells (neutrophils and monocytes) and protective lymphocytes and eosinophils, may help predict response to anti–PD-1 therapy in advanced NSCLC. Clinical trial information: NCT03088540 , NCT03409614 .