This study is designed to evaluate two different tegoprazan-based dual therapy regimens for the treatment of Helicobacter pylori (H. pylori) infection. All participants will receive tegoprazan 50 mg twice daily for 14 days, combined with one of two amoxicillin dosing schedules that contain the same total daily dose of 3 grams of amoxicillin.

One group will receive amoxicillin 1 gram three times daily (TID), which is the standard regimen. The other group will receive amoxicillin 1.5 grams twice daily (BID), an alternative schedule that may improve convenience and treatment adherence while maintaining the same total daily antibiotic amount.

A total of 240 adults with confirmed H. pylori infection will be randomly assigned to one of the two treatment groups. The main goal of the study is to compare the H. pylori eradication rates between the two regimens. Eradication will be assessed 4 to 8 weeks after completing therapy using a ¹³C-urea breath test. Safety, tolerability, and medication adherence will also be monitored.

Helicobacter pylori (H. pylori) infection is a common and clinically important condition associated with peptic ulcer disease, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Effective eradication remains essential for reducing long-term complications. Traditional proton pump inhibitor (PPI)-based regimens have faced challenges due to rising antibiotic resistance and suboptimal acid suppression.

Tegoprazan is a potassium-competitive acid blocker (P-CAB) that provides rapid, potent, and sustained gastric acid inhibition, which may enhance the effectiveness of amoxicillin-based dual therapy. Amoxicillin resistance remains low in many regions, and its efficacy is closely related to maintaining intragastric pH levels that support bacterial replication.

The standard tegoprazan dual therapy uses amoxicillin 1 gram three times daily (TID). However, TID dosing may affect patient adherence, which can influence eradication outcomes. This study explores an alternative regimen: amoxicillin 1.5 grams twice daily (BID). The two regimens deliver the same total daily dose of 3 grams of amoxicillin, but the BID schedule may improve convenience and medication compliance while maintaining appropriate pharmacodynamic exposure.

This randomized, controlled clinical trial is designed to compare the eradication efficacy, safety, and tolerability of these two dosing strategies in adults with confirmed H. pylori infection. By evaluating whether a simplified BID regimen can achieve non-inferior or superior eradication rates compared with the standard TID regimen, the study aims to provide evidence that may support more convenient dual therapy options for H. pylori management.

Inclusion Criteria:

- 1.Adults aged 18 to 70 years. 2.Confirmed Helicobacter pylori infection by ¹³C-urea breath test, stool antigen test, or gastric biopsy.

3.Able to provide written informed consent. 4.Willing and able to comply with all study procedures, including follow-up testing 4-8 weeks after treatment.

Exclusion Criteria:

• 1.Known allergy or hypersensitivity to tegoprazan, amoxicillin, or any β-lactam antibiotics.

  2.Use of antibiotics, proton pump inhibitors (PPIs), bismuth-containing agents, or potassium-competitive acid blockers within 4 weeks before screening.

  3.Severe hepatic impairment (ALT or AST > 3 × upper limit of normal). 4.Severe renal impairment (estimated glomerular filtration rate < 30 mL/min/1.73 m²).

  5.Pregnant or breastfeeding women. 6.History of gastric surgery or conditions that may affect gastrointestinal absorption.

  7.Participation in another clinical trial within the past 30 days. 8.Any condition that, in the investigator's judgment, would make the participant unsuitable for the study.

The plan for sharing individual participant data (IPD) has not yet been determined. A decision regarding IPD sharing will be made after the completion of the study and review of institutional policies and publication requirements.

This is an open-label trial. Masking is not feasible because the two study arms use different dosing frequencies (BID vs TID), which cannot be blinded to participants or study personnel.