Ilaprazole (IY-81149) sodium is an orally active proton pump inhibitor. Ilaprazole sodium irreversibly inhibits H+/K+-ATPase in a dose-dependent manner with an IC50 of 6 μM in rabbit parietal cell preparation. Ilaprazole sodium is used for the research of gastric ulcers. Ilaprazole sodium is also a potent TOPK (T-lymphokine-activated killer cell-originated protein kinase) inhibitor[1][2].

On cumulation of 14C-aminopyrine in histamine stimulated parietal cells, the IC50 of Ilaprazole (IY-81149) sodium is 9 nM[1].

Ilaprazole sodium (3-30 mg/kg; i.d.) dose-dependently inhibits gastric acid secretion[1].In anesthetized rats, Ilaprazole sodium dose-dependently increases gastric pH which is lowered by histamine infusion. In the case of i.v. injection, the ED50 of Ilaprazole sodium and Omeprazole is 1.2 and 1.4 mg/kg and in the case of i.d. administration, the ED50 of Ilaprazole sodium and omeprazole is 3.9 and 4.1 mg/kg, respectively. Ilaprazole sodium also significantly inhibits pentagastrin-stimulated gastric secretion. Its ED50 is 2.1 mg/kg and that of Omeprazole was 3.5 mg/kg with i.d. administration. In the case of i.v. injection, Ilaprazole sodium is equipotent to Omeprazole. Ilaprazole sodium also inhibits gastric acid secretion strongly in fistular rats. The ED50 of Ilaprazole sodium administered intraduodenally is 0.43 mg/kg and that of omeprazole Is 0.68 mg/kg[1]. Animal Model: Male SD rat (after pylorus ligation)[1]

[1]. Kwon D, et al. Effects of IY-81149, a newly developed proton pump inhibitor, on gastric acid secretion in vitro and in vivo. Arzneimittelforschung. 2001;51(3):204-213. [2]. Zheng M, et al. Proton pump inhibitor ilaprazole suppresses cancer growth by targeting T-cell-originated protein kinase. Oncotarget. 2017;8(24):39143-39153.