ACO/ARO/AIO-21 - Capecitabine-based chemoradiotherapy in combination with the IL-1 receptor antagonist anakinra for rectal cancer Patients: A phase I trial of the German rectal cancer study group

•Response to chemoradiotherapy in rectal cancer is highly heterogeneous, ranging from complete response to tumor progression.•Interleukin-1 signaling polarizes cancer-associated fibroblasts (CAF) towards an inflammatory phenotype and predisposes iCAFs to irradiation-induced senescence.•Targeting interleukin-1 could potentially reconstitute the tumor microenvironment and improve therapy response.•The ACO/ARO-AIO-21 phase I trial is testing the interleukin-1 receptor antagonist anakinra in combination with fluoropyrimidine-based chemoradiotherapy in rectal cancer.