The identification of effective treatments for adult T-cell leukemia-lymphoma (ATL) is limited. Conventional treatment with chemotherapy regimens is typically the standard approach, but results in relapsed or worsening disease for many patients. The purpose of this study is to evaluate the safety and effectiveness of an investigational drug called KW-0761(mogamulizumab) in patients with ATL that has returned or persists despite prior therapy, and to see how treatment with KW-0761 compares with conventional therapy. KW-0761 is an antibody designed to reduce cancer growth by targeting a protein on ATL cells called CCR4.
Patients will be randomly assigned to receive KW-0761 or a conventional treatment chosen by the investigators (either pralatrexate; gemcitabine and oxaliplatin; or dexamethasone, cisplatin, and cytarabine). Patients whose ATL continues to grow while on conventional therapy may have the option of receiving KW-0761 instead. KW-0761 is given intravenously (by vein).