P-CAB agent 2 hydrochloride is a potent and orally active potassium-competitive acid blocker and a gastric acid secretion inhibitor. P-CAB agent 2 hydrochloride inhibits H + /K + -ATPase activity with an IC 50 value of <100 nM. P-CAB agent 2 hydrochloride inhibits the hERG potassium channel with an IC 50 value of 18.69 M. P-CAB agent 2 hydrochloride shows no acute toxicity and inhibits histamine-induced gastric acid secretion.