CTLA4 and neoplasm: Two fully human mAbs that bind CTLA-4, tremelimumab (CP-675,206, Pfizer, New York, NY) and ipilimumab [22] (YervoyTM, Bristol-Myers Squibb, Princeton, NJ), have been in clinical development over the past decade [23, 24], and both agents have shown activity in inducing tumor regression in clinical studies [25, 26].