Mogamulizumab

The anti-CCR4 monoclonal antibody mogamulizumab has a targeted lysis of the ATL clone and also reduces the immunosuppressive Treg population, allowing improvement of cell-mediated immunotherapy.[4] Single-agent phase II trials in patients with ATL showed response rates ranging from 30% to 50%.[5-7][Level of evidence C3] In a phase II study that combined mogamulizumab with combination chemotherapy, 101 patients had an overall response rate of 65% (95% confidence interval [CI], 55%–75%), a median progression-free survival of 7.4 months (95% CI, 5.7–9.1), and a median overall survival (OS) of 16 months (95% CI, 10.3–21.8).[8][Level of evidence C3]

A retrospective review evaluated mogamulizumab combined with both the VCAP-AMP-VECP (vincristine, cyclophosphamide, doxorubicin, prednisone; doxorubicin, ranimustine, prednisone; vindesine, etoposide, carboplatin, prednisone) regimen and CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-based regimens versus chemotherapy alone. The review concluded that the 4-year OS rate was 46.3% in the mogamulizumab combination groups, compared with 20.6% in the chemotherapy-alone group.[9][Level of evidence C3] The best results were seen with CHOP-based regimens. Mogamulizumab is available in the United States but has not been approved by the U.S. Food and Drug Administration (FDA) for patients with ATL.

Mogamulizumab is often avoided in patients planning allogeneic SCT based on data from Japan that showed an increased risk of severe graft-versus-host disease (GVHD) in patients who received mogamulizumab before allogeneic SCT.[10] The relevance of these findings in other countries and the impact of different GVHD prophylaxis regimens in this setting remains to be determined.