Moreover, clinical trials using the SMAC mimetic BI 891065 for the targeting cIAP1, cIAP2, and XIAP in combination with the anti-PD1 antibody BI 754091 against solid tumors include the treatment of BC patients and will show whether the SMAC mimetics are helpful in the future immunotherapy of BC (NCT03166631, NCT04138823). This evidence concerns the gene BIRC2 and breast cancer.