Used primarily in the treatment of chronic lymphocytic leukemia (CLL), this antibody targets CD52, a protein found on the surface of mature lymphocytes. It depletes both B and T cells, making it effective in managing autoimmune conditions such as multiple sclerosis, particularly relapsing-remitting and secondary progressive forms. The agent is also utilized in transplant medicine to prevent graft-versus-host disease by modulating the immune system. Its immunosuppressive action allows for reduced relapse rates in certain autoimmune disorders, though it increases susceptibility to infections due to prolonged lymphocyte depletion.