The cellular level blockade assay data and tumor-bearing mice experiments results all indicate that the DPPA-1 disrupts the PD-1/PD-L1 interaction under in vivo condition.207 Aurigene developed a small peptide AUNP-12, which is an anti-PD-1 targeted immunotherapy for cancer (the structure of the compound has not been disclosed).208 The AUNP-12 inhibits the binding of PD-1 and PD-L1 under in vitro conditions (IC50 = 0.72 nM), but the time of drug metabolism was short. Here, PDCD1 is linked to neoplasm.