PDCD1 and ovarian carcinoma: Furthermore, TOPACIO trial, a phase I/II clinical trial of the PARP inhibitor niraparib in combination with the anti-PD-1 antibody pembrolizumab in recurrent ovarian cancer frequently develop resistance to platinum-based chemotherapy, demonstrated an 18% ORR and a clinical benefit rate of 65%, clearly exceeding the expected activity of niraparib or pembrolizumab as monotherapies in recurrent platinum-resistant ovarian cancer (176).