Sato T, et al. - Researchers performed this study to evaluate mogamulizumab, a humanized anti-CCR4 monoclonal antibody that targets infected cells, in patients with Human T-lymphotropic virus type 1 (HTLV-1)–associated myelopathy–tropical spastic paraparesis (HAM–TSP). In this uncontrolled, phase 1–2a study, they noted that mogamulizumab decreased the number of HTLV-1–infected cells and the levels of inflammatory markers. Rash was identified as the chief side effect.