CD274 and ovarian cancer: Initial reports of some trials show promising objective response rates (ORR) for the treatment of ovarian cancer with anti-PD-1 antibody nivolumab (ORR of 15%, n = 20 patients), and pembrolizumab (ORR 11.5%, n = 49), or an anti-PD-L1 antibody avelumab (ORR 10%, n = 124) [3, 24].