Microbiota and immune-related adverse events in cancer immunotherapy

A new Progress article published in Nature Reviews Cancer by Schneider et al. examines the growing body of evidence linking the gut microbiome to the development and progression of immune-related adverse events (irAEs) during cancer immunotherapy. The review synthesizes both clinical and preclinical data demonstrating that specific microbial compositions can influence the risk of complications such as immune checkpoint inhibitor-associated colitis, one of the most common and treatment-limiting side effects of modern immunotherapy. The authors highlight key immune–microbial interactions that underpin irAE pathogenesis and discuss emerging therapeutic strategies—including microbiome modulation—that could help mitigate these risks without compromising antitumor efficacy. The work is significant because irAEs remain a major barrier to sustained immunotherapy treatment, and understanding the microbiome's role could open new avenues for safer, more personalized cancer care.