In another phase Ib trial, 23 mCRPC patients with PD-L1 positive tumors were treated with the anti-PD1 mAb pembrolizumab; 17.4% of patients had an objective response rate, with stable disease in 34.8% of patients, and tumor size reduction in 10 of 21 assessible patients (62). This evidence concerns the gene PDCD1 and neoplasm.