Mechanisms of traditional Chinese medicine in enhancing the efficacy and reducing the toxicity of immune checkpoint inhibitors via regulation of the tumor microenvironment and gut microbiota.

Immune checkpoint inhibitors (ICIs) face challenges of drug resistance and immune-related adverse events (irAEs). Traditional Chinese medicine (TCM)-including single herbs, compounds, and active monomers-enhances ICI efficacy and reduces toxicity by remodeling the tumor immune microenvironment, regulating gut microbiota, and modulating key immune pathways. TCM also alleviates ICI-induced colitis and myocarditis, demonstrating the value of holistic and syndrome-differentiated therapy. Future research should clarify synergistic mechanisms to advance precise integration of TCM and ICI immunotherapy.