Clinical Characteristics and Pharmacokinetics Change of Long-Term Responders to Antiprogrammed Cell Death Protein 1

Hitomi Jo1,2,3, Tatsuya Yoshida1,4, Shigehiro Yagishita2

  • 1Department of Thoracic Oncology, National Cancer Center Hospital, Tokyo, Japan.

Abstract

Insights

Significant tumor shrinkage predicts long-term response to immune checkpoint inhibitors (ICIs) in advanced non-small cell lung cancer (NSCLC). However, PD-L1 expression and drug levels do not predict durable responses in NSCLC patients receiving ICIs.

Area of Science:

  • Oncology
  • Immunotherapy
  • Pharmacology

Background:

  • Immune checkpoint inhibitors (ICIs) offer durable responses in advanced non-small cell lung cancer (NSCLC), but only for a subset of patients.
  • Most patients with advanced NSCLC treated with ICIs experience disease progression, highlighting the need to identify predictors of long-term response.

Purpose of the Study:

  • To investigate the clinical factors and blood drug concentrations differentiating long-term responders (LTRs) from non-LTRs in advanced NSCLC patients treated with anti-programmed cell death protein 1 (PD-1) monotherapy.

Main Methods:

  • Retrospective analysis of advanced NSCLC patients receiving nivolumab monotherapy.
  • Defined LTRs as responders with durable clinical benefit (>2 years) and non-LTRs as those with benefit (<2 years).
  • Compared clinical factors, PD-L1 expression, and serum drug concentrations between LTRs and non-LTRs.

Main Results:

  • Of 212 patients, 35% responded to anti-PD-1 therapy (75 patients), with 39% (29 patients) classified as LTRs.
  • LTRs demonstrated significantly higher overall response rates (76% vs. 35%) and median tumor shrinkage (66% vs. 16%) compared to non-LTRs (p < 0.0001 and p < 0.001, respectively).
  • No significant differences were observed in PD-L1 expression or serum drug concentrations at 3 and 6 months between LTRs and non-LTRs.

Conclusions:

  • Significant tumor shrinkage is associated with long-term response to anti-PD-1 inhibitors in advanced NSCLC.
  • PD-L1 expression levels and drug pharmacokinetic profiles were not predictive of durable responses in this cohort of NSCLC patients.