CCR4 and adult T-cell leukemia/lymphoma: KW-0761 (mogamulizumab), developed by Kyowa Hakko Kirin (Tokyo, Japan) is an anti-CCR4 hIgG1 that favors ADCC and is clinically approved for the treatment of relapsed refractory CCR4+ adult T cell leukemia/lymphoma (ATCLL) and CTCL.