Mifamurtide, a NOD2 agonist employed as an immunoadjuvant, has secured approval in the European Union for the treatment of osteosarcoma.569 By adding mifamurtide to the conventional chemotherapy regimen of cisplatin, doxorubicin, and methotrexate, there has been an enhancement in the event-free survival (EFS) for osteosarcoma patients, with the 6-year OS rate elevating from 70 to 78% (NCT00631631).570. Here, NOD2 is linked to osteosarcoma.