Biomarkers for predicting efficacy of PD-1/PD-L1 inhibitors

Area of Science:

• Immunology
• Oncology
• Biomarker Discovery

Background:

• The programmed cell death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) pathway regulates T cell activation and impacts tumor immune evasion.
• PD-1/PD-L1 inhibitors represent a significant advancement in treating refractory tumors, but their efficacy varies widely among patients.

Purpose of the Study:

• To highlight the critical need for predictive biomarkers to identify patients most likely to benefit from PD-1/PD-L1 inhibitor therapy.
• To review current and emerging biomarkers associated with anti-PD-1/anti-PD-L1 treatment response.

Main Methods:

• Review of existing literature on biomarkers for PD-1/PD-L1 inhibitor efficacy.
• Analysis of biomarkers related to tumor immune microenvironment, intrinsic tumor features, gut microbiota, and patient history.

Main Results:

• Biomarkers such as PD-L1 expression, tumor-infiltrating lymphocytes (TILs), tumor mutational burden (TMB), and mismatch repair (MMR) deficiency are linked to treatment outcomes.
• Gut microbiota, circulating biomarkers, and patient history also show predictive potential.

Conclusions:

• A multifaceted approach integrating diverse biomarkers is essential for a comprehensive understanding of the tumor immune landscape.
• Developing a comprehensive assessment framework will improve patient selection and optimize the clinical application of PD-1/PD-L1 inhibitors.