Pixantrone: novel mode of action and clinical readouts.

INTRODUCTION: Pixantrone is a first-in-class aza-anthracenedione approved as monotherapy for treatment of relapsed or refractory aggressive diffuse B-cell non-Hodgkin's lymphoma (NHL), a patient group which is notoriously difficult to treat. It has a unique chemical structure and pharmacologic properties distinguishing it from anthracyclines and anthracenediones. Areas covered: The chemical structure and mode of action of pixantrone versus doxorubicin and mitoxantrone; preclinical evidence for pixantrone's therapeutic effect and cardiac tolerability; efficacy and safety of pixantrone in clinical trials; ongoing and completed trials of pixantrone alone or as combination therapy; and the risk of cardiotoxicity of pixantrone versus doxorubicin and mitoxantrone. Expert commentary: Currently, pixantrone is the only approved therapy for multiply relapsed or refractory NHL, an area with few available effective treatment options. Pixantrone is currently being investigated as combination therapy with other drugs including several targeted therapies, with the ultimate goal of improved survival in heavily pretreated patients. In order for pixantrone to be acknowledged in the treatment of aggressive NHL, the perception of pixantrone as an anthracycline-like agent that has anthracycline-like activity and cardiotoxicity needs to be changed. Further data from ongoing clinical trials will help in confirming pixantrone as an effective and safe option.