Vonoprazan hydrochloride, a proton pump inhibitor (PPI), effectively acts as a potassium-competitive acid blocker (P-CAB) with potent antisecretory activity. It notably inhibits H+,K+-ATPase activity in porcine gastric microsomes, demonstrating an IC50 of 19 nM at pH 6.5. Primarily developed for researching acid-related diseases like gastroesophageal reflux disease and peptic ulcer disease, vonoprazan hydrochloride also serves in the eradication of Helicobacter pylori [1] [2] [3].

Vonoprazan (0.1 nM-10 μM; 30 minutes) exhibits porcine gastric H +, K + -ATPase activity in a concentration-dependent manner [2]. Vonoprazan does not inhibit Na +,K + -ATPase activity, even at concentrations 500 times higher than their IC 50 values against gastric H +,K + -ATPase activity [2].

Vonoprazan (1-4 mg/kg; p.o.) completely inhibits basal and 2-deoxy-D-glucose (200 mg/kg; s.c.)-stimulated gastric acid secretion at the 4 mg/kg dose in rats [2]. Animal Model: Male 7- or 8-week-old Sprague-Dawley rat [2] Dosage: 0.5 mg/kg, 1 mg/kg, 2 mg/kg, 4 mg/kg Administration: Oral administration Result: Inhibited basal gastric acid secretion in a dose-dependent manner.