(HealthDay)—For patients with human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy-tropical spastic paraparesis (HAM-TSP), treatment with the humanized anti-CCR4 monoclonal antibody that targets infected cells, mogamulizumab, decreases the number of HTLV-1-infected cells, according to a study published in the Feb. 8 issue of the New England Journal of Medicine.