Effect on Intragastric pH of a PPI with a Prolonged Plasma Half-Life: Comparison between Tenatoprazole and Esomeprazole on the Duration of Acid Suppression in Healthy Male Volunteers

• Published in: The American journal of gastroenterology Vol. 100; no. 9; pp. 1949 - 1956
• Main Authors: HUNT, Richard H, ARMSTRONG, David, JAMES, Cindy, CHOWDHURY, Sadat K, YUHONG YUAN
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing 01.09.2005; Wolters Kluwer Health Medical Research, Lippincott Williams & Wilkins
• Subjects: 2-Pyridinylmethylsulfinylbenzimidazoles; Adolescent; Adult; Anti-Ulcer Agents - administration & dosage; Anti-Ulcer Agents - blood; Anti-Ulcer Agents - pharmacokinetics; Anti-Ulcer Agents - pharmacology; Bacterial diseases; Bacterial diseases of the digestive system and abdomen; Biological and medical sciences; Cross-Over Studies; Esomeprazole - administration & dosage; Esomeprazole - analogs & derivatives; Esomeprazole - blood; Esomeprazole - pharmacokinetics; Esomeprazole - pharmacology; Gastric Acidity Determination; Gastroenterology; Gastroenterology. Liver. Pancreas. Abdomen; Half-Life; Human bacterial diseases; Humans; Imidazoles - administration & dosage; Imidazoles - blood; Imidazoles - pharmacokinetics; Imidazoles - pharmacology; Infectious diseases; Male; Medical sciences; Proton Pump Inhibitors; Pyridines - administration & dosage; Pyridines - blood; Pyridines - pharmacokinetics; Pyridines - pharmacology; Stomach - drug effects; H; Spirillaceae; Male; Antiulcer agent; Tenatoprazole; K; Proton pump inhibitor; Blood plasma; Helicobacter pylori; Antisecretory agent; Gastroenterology; pH; Bacteria; Half life; Human; Spirillales; Healthy subject; Enzyme; Enzyme inhibitor; Duration; Benzimidazole derivatives; Esomeprazole; exchanging ATPase; Hydrolases; Comparative study
• ISSN: 0002-9270; 1572-0241
• DOI: 10.1111/j.1572-0241.2005.41956.x

To compare the inhibitory effect of a novel proton pump inhibitor (PPI), tenatoprazole 40 mg once daily, with esomeprazole 40 mg once daily on intragastric acidity. A randomized, investigator-blind, two-way, crossover study was conducted in 30 healthy Helicobacter pylori negative male volunteers. Tenatoprazole 40 mg or esomeprazole 40 mg was administered once daily for 7 consecutive days with a 4-wk washout period between treatments. Ambulatory 24-h intragastric pH was recorded at baseline, after 7 days' treatment, and 3 and 5 days after treatment was stopped. At presumed steady-state (day 7), median 24-h pH values were 5.02 and 4.79 for tenatoprazole and esomeprazole, respectively. There was a significant difference between tenatoprazole and esomeprazole during the nocturnal period when mean pH was 4.64 +/- 0.67 versus 3.61 +/- 0.90, respectively (p < 0.0001), as well as a significantly higher mean percentage of time with pH >4 on tenatoprazole (72.5 +/- 14.9 vs 62.2 +/- 13.6, p < 0.0001). The effect of tenatoprazole was still present 5 days after treatment withdrawal especially during the night-time. The mean area under the plasma concentration-time curve and elimination half-time was significantly higher in the tenatoprazole group as compared with the esomeprazole group. Tenatoprazole 40 mg daily provides a prolonged duration of acid suppression and a shorter nocturnal acid breakthrough in healthy volunteers, even after stopping the drug. Thus, tenatoprazole may provide greater clinical efficacy for patients in whom a once daily PPI is ineffective. Further studies are indicated.