The First-week Proliferative Response of Peripheral Blood PD-1 + CD8 + T Cells Predicts the Response to Anti-PD-1 Therapy in Solid Tumors

Clin Cancer Res. 2019 Apr 1;25(7):2144-2154. doi: 10.1158/1078-0432.CCR-18-1449. Epub 2019 Jan 15.


Purpose: To investigate blood-based dynamic biomarkers that predict responses to anti-programmed cell death protein 1 (PD-1) therapy in solid tumors.

Experimental design: Preplanned biomarker analysis was performed as part of a phase II clinical trial (NCT02607631) in patients with metastatic or refractory thymic epithelial tumors (TETs; n = 31) who received pembrolizumab. The biomarker was further tested in an independent cohort of prospectively recruited patients with metastatic non-small cell lung cancer (NSCLC) who received pembrolizumab or nivolumab (NSCLC cohort 1; n = 33) and validated in an independent cohort of patients with NSCLC (NSCLC cohort 2; n = 46). Peripheral blood samples were obtained immediately before treatment (D0) and 7 days after the first dose (D7) and analyzed using multi-color flow cytometry.

Results: A higher fold-change in the percentage of Ki-67+ cells among PD-1+CD8+ T cells 7 days after the first dose (Ki-67D7/D0) significantly predicted durable clinical benefit (DCB; P < 0.001) and prolonged progression-free survival (PFS; P = 0.027) in patients with TETs. Ki-67D7/D0 ≥ 2.8 was also associated with better DCB, PFS, and overall survival (OS) in NSCLC cohort 1 (all P < 0.05). Ki-67D7/D0 was subsequently validated in NSCLC cohort 2, and Ki-67D7/D0 ≥ 2.8 significantly predicted better DCB (P = 0.001), PFS (P = 0.002), and OS (P = 0.037). Ki-67D7/D0 had a low correlation with tumor PD-L1 expression and combining both factors did not improve the predictive power of Ki-67D7/D0.

Conclusions: The proliferative response of peripheral blood PD-1+CD8+ T cells, measured as the fold-change in the percentage of Ki-67+ cells 7 days after treatment (Ki-67D7/D0), may be a useful surrogate biomarker for predicting the response and prognosis to anti-PD-1 therapy in solid tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antineoplastic Agents, Immunological / pharmacology
  • Antineoplastic Agents, Immunological / therapeutic use*
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Biomarkers, Tumor*
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / metabolism*
  • Cell Proliferation / drug effects
  • Female
  • Flow Cytometry
  • Humans
  • Lymphocyte Count
  • Male
  • Middle Aged
  • Molecular Targeted Therapy
  • Neoplasms / blood*
  • Neoplasms / diagnosis
  • Neoplasms / drug therapy*
  • Neoplasms / mortality
  • Programmed Cell Death 1 Receptor / antagonists & inhibitors
  • Programmed Cell Death 1 Receptor / metabolism*
  • ROC Curve
  • Survival Analysis
  • Time Factors
  • Treatment Outcome


  • Antineoplastic Agents, Immunological
  • Biomarkers, Tumor
  • Programmed Cell Death 1 Receptor

Associated data