European phase II study of mogamulizumab, an anti-CCR4 monoclonal antibody, in relapsed/refractory peripheral T-cell lymphoma.

CC chemokine receptor 4 (CCR4), the receptor for macrophage-derived chemokine (MDC/CCL22) and thy-mus activation-regulated chemokine (TARC/CCL17), is expressed on tumor cells in approximately 30-65% of patients with peripheral T-cell lymphoma (PTCL). Mogamulizumab, a defucosylated, humanized, IgG1 monoclonal antibody directed against CCR4 has been approved in Japan for the treatment of CCR4-positive relapsed/refractory PTCL. Mogamulizumab demonstrated effectiveness [overall response rate (ORR) 34%] in a phase II study of 29 Japanese patients with relapsed CCR4-positive PTCL. 2 We conducted a phase II study in patients with relapsed or refractory CCR4-positive PTCL at 15 European centers (clinicaltrials.gov identifier :01611142). All patients gave written informed consent prior to enrollment. The study was conducted in accordance with the Declaration of Helsinki and in compliance with Good Clinical Practice guidelines. The protocol was approved by the Ethics Committee at each participating institution. The primary objective was to determine the best ORR of mogamulizumab. Secondary objectives included the duration of response, progression-free survival (PFS), and overall survival (OS) as well as the safety and immunogenicity of mogamulizumab. Adult patients of either sex with CCR4-positive, measurable PTCL who had failed prior therapy (relapsed or refractory) were recruited. Histologically confirmed diagnosis of PTCL according to the 2008 WHO classification 3