XR11576

XR11576 (also known as MLN576) is a novel monophenazine derivative that acts as an orally active inhibitor of both DNA topoisomerase I and II. It exhibits cytotoxic activity against a range of human and murine tumor cell lines and has demonstrated greater potency than several other cytotoxic agents in ex vivo studies. The drug was developed for the treatment of solid tumors, including breast and gynecological malignancies, with some investigation in acute lymphoblastic leukemia. Its mechanism involves modulating the activity of DNA topoisomerase I (TOP1) and DNA topoisomerase II (TOP2), enzymes critical for DNA replication and cell division[1][2][3][5][6][7].