Rational Immune Checkpoint Inhibitor-Based Combination Immunotherapy in Cancer: Mechanistic Design, Biomarker...

Area of Science:

• Oncology
• Immunology
• Translational Medicine

Background:

• Cancer immunotherapy, particularly immune checkpoint blockade, has revolutionized cancer treatment.
• Durable clinical benefit remains elusive for many patients due to biological and clinical resistance mechanisms.

Purpose of the Study:

• To review current combination immunotherapy strategies addressing key barriers to antitumor response.
• To synthesize evidence on biologically rational approaches integrating immune checkpoint blockade with other modalities.
• To explore the role of integrated biomarkers in patient selection for combination therapies.

Main Methods:

• Targeted narrative review of peer-reviewed literature (PubMed, Scopus, Web of Science, Jan 2020-Apr 2026).
• Inclusion of landmark studies for mechanistic context.
• Evidence synthesis focused on barriers like poor immune priming, exclusion, and immunosuppressive tumor microenvironments.

Main Results:

• Combination immunotherapy is moving from empiric to biologically rational designs.
• Integration strategies include chemotherapy, radiotherapy, targeted agents, vaccines, and cellular therapies.
• Emphasis on integrated biomarkers combining tumor, immune, spatial, and dynamic features for patient selection.

Conclusions:

• The field is evolving towards mechanism-matched, biomarker-guided strategies.
• These approaches aim to broaden and refine the benefits of cancer immunotherapy.
• Challenges include managing regimen complexity, toxicity, and multidisciplinary implementation.