Mogamulizumab is a monoclonal antibody used in the treatment of certain types of blood cancers, specifically cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL). Mogamulizumab targets and binds to CC chemokine receptor 4 (CCR4), which is expressed on the surface of malignant T-cells in certain types of lymphomas. By binding to CCR4, mogamulizumab mediates antibody-dependent cellular cytotoxicity (ADCC) and induces apoptosis (programmed cell death) in the cancer cells. It is indicated for the treatment of adult patients with relapsed or refractory CTCL and PTCL. These are types of non-Hodgkin lymphoma that primarily affect T-cells and can present with skin manifestations (in the case of CTCL).