CTLA4 and metastatic melanoma: In a phase II, double-blind trial, the combination of ipilimumab and nivolumab was reported to show better objective clinical responses and progression-free survival than ipilimumab alone [6] And in a phase I clinical trial, the anti-CD40 monoclonal antibody CP-870,893 was combined safely with the CTLA4 inhibitor tremelimumab in patients with metastatic melanoma, with non-overlapping side effects reported as well as clinical responses.