IPR-803 is an effective inhibitor of the uPAR·uPA protein-protein interaction (PPI) with anti-tumor activity. IPR-803 binds directly to uPAR with a Ki of 0.2 μM.

PPI:ki： 0.2 μM

IPR-803 (0-200 μM; 3 days) blocks the invasion of MDA-MB-231 cells, and most of the inhibition of cell invasion is unlikely due to the cytotoxicity of the compound. IPR-803 (50 μM; 30 minutes) shows inhibition of MAPK phosphorylation. IPR-803 blocks invasion of breast cancer cells line MDA-MB-231, and inhibits matrix metalloproteinase breakdown of the extracellular matrix. IPR-803 impairs MDA-MB-231 cell adhesion and migration. IPR-803 induces a concentration-dependent impairment of cell adhesion with an IC50 of 30 μM. IPR-803 inhibits MDA-MB-231 cells growth with an IC50 of 58 μM[1].

In NSG mice with MDA-MB-231 cells xenograft, IPR-803 (200 mg/kg; i.g.; three times a week; for 5 weeks) impairs breast cancer metastasis with a t1/2 of 5 hours. IPR-803 has a low oral bioavailability at 4 percent, and remains high concentration even after 10 hours in tumor tissue[1].