CCR4 antagonists are used in the United States for the treatment of mycosis fungoides and Sézary disease, and used globally for the treatment of adult T-cell leukemia/lymphoma (ATCLL) and CCR4+ cutaneous T cell lymphoma (CTCL) (Yu et al., 2007; FDA, 2018). The gene discussed is CCR4; the disease is primary cutaneous T-cell non-Hodgkin lymphoma.