CAMBRIDGE, Mass.--(BUSINESS WIRE)--Xanthus Pharmaceuticals, Inc. today announced results from three collaborative in vitro studies into the mechanism of action of Xanafide® (amonafide malate). Xanafide is a topoisomerase II inhibitor that is currently in a pivotal Phase 3 trial under a special protocol agreement (SPA) with the FDA for the treatment of secondary acute myeloid leukemia (AML). These in vitro studies, presented on April 13 and 14 at the American Association for Cancer Research (AACR) Annual meeting demonstrated how Xanafide acts differently from classical topoisomerase inhibitors such as daunorubicin.