thiotepa + fludarabine + cytarabine + mitoxantrone

This combination is an investigational chemotherapeutic regimen consisting of **thiotepa** (an alkylating agent), **fludarabine** (a purine nucleoside analog), **cytarabine** (a pyrimidine nucleoside analog), and **mitoxantrone** (an anthracenedione topoisomerase II inhibitor). The mechanism of action involves multiple pathways leading to inhibition of DNA synthesis and repair, cell cycle arrest, and apoptosis of rapidly dividing hematologic malignant cells. Used as a multi-agent therapy, similar regimens are primarily developed as conditioning regimens prior to hematopoietic stem cell transplantation or as salvage therapy for relapsed/refractory acute myeloid leukemia (AML) and related hematologic malignancies[1][5]. Each component has established use in AML and transplantation settings, though this specific four-drug combination is not associated with a codified protocol under a single name in current guidelines but reflects a rational combination based on synergistic antineoplastic effects[5].