PDCD1 and pancreatic neoplasm: Most clinical trials at various stages targeting PD-1 in pancreatic cancer are currently recruiting or ongoing (Table 1), including a Phase 1 clinical trial (NCT04181645) with an estimated termination date in 2022 evaluating the safety and efficacy of the combination treatment of SHR-1210 (a humanized anti-PD1 monoclonal antibody), nab-paclitaxel, and gemcitabine in a cohort of metastatic PDAC patients.