CTLA4 and melanoma: Thus, a fully humanized anti-CTLA-4 monoclonal antibody immunoglobulin (Ig) G1 isotype (ipilimumab) was approved by the Food and Drug Administration (FDA) in 2011 at a dosage of 3 mg/kg every 3 weeks for four cycles in advanced melanoma, with evidence of improved survival [7, 8].