Treatment with single-agent CTLA-4 directed monoclonal antibodies has achieved 19%-25% 5-year survival.13 Treatment with PD-1 antibodies increased 5-year survival to the 34%-42% range and proved superior to CTLA-4 directed monotherapy.2,14 Combination therapy with PD-1 plus CTLA-4 antibodies has now achieved a 5-year survival of over 50%.1 The optimal treatment duration for CKI therapy in metastatic melanoma patients remains unknown. Here, CTLA4 is linked to metastatic melanoma.