TAK-438

TAK-438 is a novel potassium-competitive acid blocker (P-CAB) type antisecretory agent that reversibly inhibits gastric H+, K+-ATPase with a K(i) of 10 nM at pH 7. TAK-438 exhibited potent H(+),K(+)-ATPase inhibitory activity and potent gastric acid secretion inhibitory action in vivo. TAK-438 increased the pH of the gastric perfusate to 5.7 in an unstimulated condition, and this effect was maintained in the presence of subsequent histamine stimulation. TAK-438 exerted a more potent and longer-lasting antisecretory effect than lansoprazole through high accumulation and slow clearance from the gastric tissue. In addition, TAK-438 was unaffected by the gastric secretory state, unlike proton pump inhibitors (PPIs).