Objective:

To evaluate the relationship between the gut microbiome and immune checkpoint inhibitors (ICIs) efficacy, focusing on functional convergence despite taxonomic diversity.

Approach:

• Bibliometric Mapping: Analysis of 2,195 publications indexed in the Web of Science Core Collection from 2013 to 2025 to assess scientific production and thematic evolution.
• Clinical Trials Analysis: Secondary analysis of ClinicalTrials.gov to evaluate interventional activity related to microbiome and ICI research.
• Functional Integration: Cross-cohort analysis of clinical and preclinical studies to identify shared immunological pathways linked to microbiome–ICI interactions.

Key Findings:

• Publication output increased steadily, with a notable rise in translational research post-2018.
• Thematic focus shifted from mechanistic studies to clinically oriented and intervention-driven research.
• Despite variability in response-associated taxa, functional integration indicated convergence in immunomodulatory pathways.

Interpretation:

Taxonomic inconsistencies in microbiome–ICI studies may reflect underlying functional convergence rather than biological contradiction.

Limitations:

• Variability in reported taxa across studies limits reproducibility.
• Methodological differences in donor selection and sequencing complicate direct comparisons.

Conclusion:

Findings support a shift towards function-based frameworks for biomarker discovery and microbiome-directed immunomodulation.