PD-1/PD-L1-IN-9 hydrochloride is a potent and orally active inhibitor of PD-1/PD-L1 interaction, with an IC50 of 3.8 nM. PD-1/PD-L1-IN-9 hydrochloride can enhance the killing activity of tumor cells by immune cells. PD-1/PD-L1-IN-9 hydrochloride also exhibits significant in vivo antitumor activity in a CT26 mouse model.In Vitro:PD-1/PD-L1-IN-9 hydrochloride (compound 24) (46.9-1500 nM; pretreated for 2 h) dose-dependently significantly activates the antitumor immunity of peripheral blood mononuclear cells (PBMCs) to MDB-MB 231 cells, with an EC50 of ～100 nM.In Vivo:PD-1/PD-L1-IN-9 hydrochloride (compound 24) (40-80 mg/kg; p.o.; once a day for 2 weeks) inhibits tumor growth in a dose-dependent manner and does not cause any body weight loss or mortality of mice.
PD-1/PD-L1-IN-9 hydrochloride (3 mg/kg; i.v.; single dose) exhibits half-life (T1/2=4.2 h), plasma clearance (Cl=11.5 L/h/kg) and Cmax (1233 ng/mL) in rats.
PD-1/PD-L1-IN-9 hydrochloride (25 mg/kg; p.o.; single dose) exhibits moderate oral bioavailability (F=22 %), half-life (t1/2=6.4 h) and Cmax (192 ng/mL) in rats.