Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 axis induce sustained clinical responses in a sizeable minority of cancer patients. Toxicity represents the major cause of reduced dosage, delayed drug administration and therapy discontinuation.
Changes occurring in the gut microbiota composition have been proposed as a mechanism to explain the pathogenesis of immune-related toxicity. Furthermore, cancer patients responding to the treatment with ICIs show enhanced anti-tumor immunity with a “favorable” gut microbiome.
The CALADRIO project is a sub-study of the KELLY trial (MedOPP127) with the interest to characterize the microbiome as a potential predictive factor of response to anti-PD-1 immunotherapy pembrolizumab in patients with HR-positive/HER2-negative metastatic breast cancer previously treated with anthracyclines and taxanes.
The main objective is to analyze the variation of microbiota’s phylum distribution in fecal and oral samples from patients with HR-positive/HER2-negative MBC treated with pembrolizumab and eribulin at the EoT.