Efficacy of TAK-438, Amoxicillin and Clarithromycin in the First Line Eradication of H. Pylori

Inclusion Criteria: 1. Participants must be H. pylori-positive patients at baseline (Visit 1) 2. Participants must be endoscopically confirmed to have scarred gastric ulcer or duodenal ulcer at baseline (Visit 1). However, if a history of ulcers is confirmed by the medical interview or previous medical record, Participants whose gastric ulcer scar or duodenal ulcer scar has disappeared may be included in the study. 3. Outpatient (including inpatient for examination) Exclusion Criteria: 1. Participants who have received H.pylori eradication treatment 2. Participants who have either acute upper gastrointestinal bleeding, gastric ulcer \[mucosal defect (with white coating including clot adherence) of 3 mm or larger in size\], duodenal ulcer \[mucosal defect (with white coating including clot adherence) of 3 mm or larger in size\], acute gastric mucosal lesion (AGML), or acute duodenal mucosal lesion (ADML) on endoscopic examination at baseline (Visit 1). However, participants with gastric erosion or duodenal erosion may be included in the study. 3. Participants who have received or who are scheduled to undergo surgery which affects gastric acid secretion (ex, resection of upper gastrointestinal tract, vagotomy, etc) 4. Participants who cannot be treated with medicinal treatment (ex, perforation, pyloric stenosis or large hemorrhage, etc) 5. Participants with a previous or current history of Zollinger-Ellison syndrome, or other gastric acid hypersecretion disorders 6. Participants with hepatic or renal impairment receiving treatment with colchicines 7. Participants who have a history of hypersensitivity or allergy to TAK-438 (including its excipients), PPIs, penicillin antibiotics, macrolide antibiotics, or antitrichomonal agents 8. Participants with infectious mononucleosis 9. Participants with an organic disease of the brain or spinal cord