Phase 3 to Evaluate the Efficacy and Safety of DWP14012 in Patients With Gastric Ulcer

• DWP14012 40mg (Fexuprazan) (Drug): DWP14012 40mg(Fexuprazan) + placebo of Lansoprazole
• Lansoprazole 30mg (Drug): Lansoprazole 30mg + Placebo of DWP14012 40mg

Primary outcomes

• Cumulative gastric ulcer healing rate confirmed by upper gastrointestinal endoscopy through Week 8 [Week 8]

Secondary outcomes

• Gastric ulcer healing rate confirmed by upper gastrointestinal endoscopy at Week 4 [Week 4]
• Gastric ulcer healing rate confirmed by upper gastrointestinal endoscopy at Week 4 according to H. pylori infection status. [Week 4]
• Cumulative gastric ulcer healing rate confirmed by upper gastrointestinal endoscopy through Week 8 according to H. pylori infection status. [Week 8]
• Changes in NDI scores at Weeks 4 and 8. [Week 4 and Week 8]
• Changes in the number of gastric ulcers at Weeks 4 and 8. [Week 4 and Week 8]
• Change from baseline in gastric ulcer size assessed by upper gastrointestinal endoscopy [Week 4 and Week 8]
• Percentage change from baseline in gastric ulcer size assessed by upper gastrointestinal endoscopy at Week 4 and Week 8 [Week 4 and Week 8]

Sex: All, ages: 19 Years to any

Inclusion Criteria:

1. At least one gastric ulcer is present, and the largest gastric ulcer measures ≥ 3 mm and ≤ 30 mm in diameter
2. The Sakita-Miwa classification of the largest gastric ulcer is A1 or A2.

Exclusion Criteria:

1. Participants with a history of Zollinger-Ellison syndrome or conditions associated with gastric hypersecretion.
2. Participants who, within 30 days prior to the screening visit (Visit 1), have undergone or are scheduled to undergo major surgery that may affect gastric acid secretion.
3. Participants with a history of malignancy within 5 years prior to the screening visit (Visit 1); gastrointestinal malignancies are excluded regardless of the time elapsed.
4. Participants who, at the screening visit (Visit 1), have gastrointestinal active bleeding , esophageal stricture, ulcer-induced stenosis, pyloric stenosis, gastroesophageal varices, Barrett's esophagus (> 3 cm), esophageal dysplasia, duodenal ulcer, refractory ulcer, perforated ulcer, or surgery-induced ulcer
5. Participants who, at the screening visit (Visit 1), have pancreatitis or inflammatory bowel disease (including Crohn's disease, ulcerative colitis, or intestinal Behçet's disease).