{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T02:18:23Z","timestamp":1771035503235,"version":"3.50.1"},"reference-count":36,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2012,1,6]],"date-time":"2012-01-06T00:00:00Z","timestamp":1325808000000},"content-version":"vor","delay-in-days":311,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["accpjournals.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Pharmacotherapy"],"published-print":{"date-parts":[[2011,3]]},"abstract":"<jats:p><jats:bold>Study Objective.<\/jats:bold> To determine the factors that may influence <jats:italic>Helicobacter pylori<\/jats:italic> eradication in patients receiving omeprazole\u2010amoxicillin dual therapy.<\/jats:p><jats:p><jats:bold>Design.<\/jats:bold> Prospective, randomized study.<\/jats:p><jats:p><jats:bold>Setting.<\/jats:bold> University\u2010affiliated hospital in Taiwan.<\/jats:p><jats:p><jats:bold>Patients.<\/jats:bold> A total of 128 adults (age range 20\u201375 yrs) with <jats:italic>H. pylori<\/jats:italic>\u2010positive duodenal ulcer were enrolled; 121 completed the final evaluation.<\/jats:p><jats:p><jats:bold>Intervention.<\/jats:bold> Patients were randomly assigned to one of four omeprazole\u2010amoxicillin treatment groups, with each treatment administered for 2 weeks: O2A2 group (33 patients)\u2014omeprazole 20 mg twice\/day plus amoxicillin 500 mg 4 times\/day; O2A1 group (32 patients)\u2014omeprazole 20 mg twice\/day plus amoxicillin 250 mg 4 times\/day; O1A2 group (32 patients)\u2014omeprazole 20 mg once\/day plus amoxicillin 500 mg 4 times\/day; and O1A1 group (31 patients)\u2014omeprazole 20 mg once\/day plus amoxicillin 250 mg 4 times\/day<\/jats:p><jats:p><jats:bold>Measurements and Main Results.<\/jats:bold> Data were collected on <jats:italic>H. pylori<\/jats:italic> status, histologic parameters, antibiotic resistance, intragastric pH, cytochrome P450 (CYP) 2C19 genotype, and adverse reactions. The intent\u2010to\u2010treat cure rates (95% confidence interval [CI]) in groups O2A2, O2A1, O1A2, and O1A1 were 76% (95% CI 59\u201387%), 72% (95% CI 54\u201384%), 50% (95% CI 34\u201366%) and 52% (95% CI 35\u201368%), respectively. Eradication of <jats:italic>H pylori<\/jats:italic> infection was statistically significantly dependent on omeprazole dosage, CYP2C19 genotype, age, gastritis status, and <jats:italic>H. pylori<\/jats:italic> density. All CYP2C19 poor metabolizers were cured, whereas the <jats:italic>H pylori<\/jats:italic> cure rate in CYP2C19 extensive metabolizers varied from 44\u201376% in the different treatment groups. Eradication of <jats:italic>H. pylori<\/jats:italic> was favored in the omeprazole higher dose groups versus the lower dose groups (79% vs 53%, p=0.004). No secondary antibiotic resistance was found. Thirty\u2010seven (95%) of 39 patients who failed with the initial treatment were cured by subsequent antibiotic susceptibility\u2010driven proton pump inhibitor\u2010based triple therapy.<\/jats:p><jats:p><jats:bold>Conclusion.<\/jats:bold> Provided a maintenance dose of amoxicillin is given every 6 hours, eradication of <jats:italic>H pylori<\/jats:italic> infection was significantly dependent on omeprazole dosage, CYP2C19 genotype, age, gastritis status, and <jats:italic>H pylori<\/jats:italic> density.<\/jats:p>","DOI":"10.1592\/phco.31.3.227","type":"journal-article","created":{"date-parts":[[2011,3,9]],"date-time":"2011-03-09T10:41:46Z","timestamp":1299667306000},"page":"227-238","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Role of Omeprazole Dosage and Cytochrome P450 2C19 Genotype in Patients Receiving Omeprazole\u2010Amoxicillin Dual Therapy for <i>Helicobacter pylori<\/i> Eradication"],"prefix":"10.1002","volume":"31","author":[{"given":"Jyh\u2010Chin","family":"Yang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hong\u2010Long","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Herng\u2010Der","family":"Chern","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chia\u2010Tung","family":"Shun","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bor\u2010Ru","family":"Lin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chun\u2010Jung","family":"Lin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teh\u2010Hong","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2012,1,6]]},"reference":[{"key":"e_1_2_1_2_2","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMra020542"},{"key":"e_1_2_1_3_2","doi-asserted-by":"publisher","DOI":"10.1136\/gut.2006.101634"},{"key":"e_1_2_1_4_2","doi-asserted-by":"publisher","DOI":"10.1023\/A:1005457226341"},{"key":"e_1_2_1_5_2","doi-asserted-by":"publisher","DOI":"10.1136\/gut.2003.022111"},{"issue":"3","key":"e_1_2_1_6_2","first-page":"437","article-title":"Evolution of resistance of Helicobacter pylori to metronidazole and clarithromycin in Taiwan","volume":"59","author":"Yang JC","year":"1998","journal-title":"Digestion"},{"key":"e_1_2_1_7_2","first-page":"234","article-title":"Anti\u2010Helicobacter pylori therapy","volume":"24","author":"Yang JC","year":"2007","journal-title":"Gastroenterol J Taiwan"},{"key":"e_1_2_1_8_2","doi-asserted-by":"publisher","DOI":"10.1007\/s100960100611"},{"key":"e_1_2_1_9_2","doi-asserted-by":"publisher","DOI":"10.7326\/0003-4819-136-1-200201010-00008"},{"key":"e_1_2_1_10_2","doi-asserted-by":"publisher","DOI":"10.1007\/s100960000288"},{"key":"e_1_2_1_11_2","doi-asserted-by":"publisher","DOI":"10.1053\/j.gastro.2007.07.008"},{"key":"e_1_2_1_12_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2036.1994.tb00303.x"},{"key":"e_1_2_1_13_2","doi-asserted-by":"publisher","DOI":"10.1097\/00008571-199702000-00008"},{"key":"e_1_2_1_14_2","doi-asserted-by":"publisher","DOI":"10.1517\/17425250903386251"},{"key":"e_1_2_1_15_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.clpt.2005.10.002"},{"key":"e_1_2_1_16_2","doi-asserted-by":"publisher","DOI":"10.1097\/00000478-199610000-00001"},{"key":"e_1_2_1_17_2","first-page":"1","article-title":"A multicenter study on eradication of Helicobacter pylori infection in patients with duodenal ulcer by lansoprazole\u2010antibiotics combined therapy","volume":"32","author":"Yang JC","year":"1999","journal-title":"J Microbiol Immunol Infect"},{"key":"e_1_2_1_18_2","doi-asserted-by":"publisher","DOI":"10.1592\/phco.23.6.711.32177"},{"key":"e_1_2_1_19_2","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1016\/S0026-895X(25)09788-3","article-title":"Identification of a new genetic defect responsible for the polymorphism of (S)\u2010mephenytoin metabolism in Japanese","volume":"46","author":"Morais SMF","year":"1994","journal-title":"Mol Pharmacol"},{"key":"e_1_2_1_20_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0021-9258(17)40694-6"},{"key":"e_1_2_1_21_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2036.2002.01173.x"},{"key":"e_1_2_1_22_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2125.1997.00551.x"},{"key":"e_1_2_1_23_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.40.5.1327"},{"key":"e_1_2_1_24_2","doi-asserted-by":"publisher","DOI":"10.2165\/00003088-199835050-00004"},{"key":"e_1_2_1_25_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.39.8.1859"},{"key":"e_1_2_1_26_2","doi-asserted-by":"publisher","DOI":"10.1093\/jac\/39.1.5"},{"key":"e_1_2_1_27_2","first-page":"1415","article-title":"Variability with omeprazole\u2010amoxicillin combinations for treatment of Helicobacter pylori infection","volume":"90","author":"Graham KS","year":"1995","journal-title":"Am J Gastroenterol"},{"key":"e_1_2_1_28_2","doi-asserted-by":"publisher","DOI":"10.1080\/00365529850166185"},{"key":"e_1_2_1_29_2","doi-asserted-by":"publisher","DOI":"10.1053\/gast.2000.16515"},{"key":"e_1_2_1_30_2","doi-asserted-by":"publisher","DOI":"10.1016\/0016-5085(95)90689-4"},{"key":"e_1_2_1_31_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1523-5378.2003.00158.x"},{"key":"e_1_2_1_32_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2125.2009.03393.x"},{"key":"e_1_2_1_33_2","doi-asserted-by":"publisher","DOI":"10.1097\/00008571-200106000-00009"},{"key":"e_1_2_1_34_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1572-0241.2006.00717.x"},{"key":"e_1_2_1_35_2","doi-asserted-by":"publisher","DOI":"10.1136\/gut.37.1.39"},{"key":"e_1_2_1_36_2","doi-asserted-by":"publisher","DOI":"10.1136\/gut.46.3.321"},{"key":"e_1_2_1_37_2","first-page":"1316","article-title":"Genetic analysis of the cytotoxin\u2010associated gene and the vacuolating toxin gene in Helicobacter pylori strains isolated from Taiwanese patients","volume":"92","author":"Yang JC","year":"1997","journal-title":"Am J Gastroenterol"}],"container-title":["Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1592%2Fphco.31.3.227","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/accpjournals.onlinelibrary.wiley.com\/doi\/pdf\/10.1592\/phco.31.3.227","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T15:58:22Z","timestamp":1761062302000},"score":1,"resource":{"primary":{"URL":"https:\/\/accpjournals.onlinelibrary.wiley.com\/doi\/10.1592\/phco.31.3.227"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,3]]},"references-count":36,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2011,3]]}},"alternative-id":["10.1592\/phco.31.3.227"],"URL":"https:\/\/doi.org\/10.1592\/phco.31.3.227","archive":["Portico"],"relation":{},"ISSN":["0277-0008","1875-9114"],"issn-type":[{"value":"0277-0008","type":"print"},{"value":"1875-9114","type":"electronic"}],"subject":[],"published":{"date-parts":[[2011,3]]},"assertion":[{"value":"2012-01-06","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}