Study of KW-0761 in Subjects With CCR4-positive Peripheral T/NK-cell Lymphoma

Inclusion Criteria: * Subjects with hematologically or pathohistologically diagnosed peripheral T/NK-cell lymphoma * Subjects who have been positive for CCR4 * Subjects who received one or more chemotherapy regimens * Subjects who relapse after achieving complete response, uncertain complete response or partial response by the last chemotherapy * Subjects who have an interval of 4 weeks or more between the last day of the prior therapy and the scheduled day of the first KW-0761 treatment * Subjects with nodal lesions, extranodal lesions and/or cutaneous lesions * Subjects who have a performance status of 0 to 2 * Subjects who are negative for HBs antigen and reported as "not detected" for HBV-DNA * Subjects who are negative for anti-HCV antibody * Subjects who have normal function of the major organs * Subjects who have given written voluntary informed consent to participate in the study Exclusion Criteria: * Subjects who underwent transplant therapy such as hematopoietic stem-cell transplantation (Subjects who underwent autologous hematopoietic stem-cell transplantation following chemotherapy will not be excluded) * Subjects who are known carriers of HIV * Subjects who have active multiple cancer * Subjects who have a history of allergic reactions to therapeutic antibodies * Subjects requiring continuous systemic treatment with steroid * Subjects who require emergency radiotherapy for treating the symptoms caused by bulky masses at enrollment or who may require such radiotherapy after the start of the study * Subjects who are pregnant, lactating or of childbearing potential, or who are planning to have children