Background：Helicobacter pylori infection is a well-established risk factor for peptic ulcer disease and gastric cancer. It's now a consensus of experts that H.pylori infection should be treated once it is recognized. Extended proton pump inhibitor (PPI)-based sequential therapy as one of the most commonly used first-line regimens provides a satisfactory eradication rate of 90.7% (95% CI, 87.4% - 94.0%). Nevertheless, its complexity of the "sequential" usage is sometimes confusing to the patients and may lead to treatment failure. The emerging new regimen - vonoprazan-based dual therapy, on the other hand, is another appealing choice with simplicity, and low pill burden. However, there's still no evidence regarding the use of vonoprazan-based dual therapy with high-dose amoxicillin (1000mg twice daily) as the first-line regimen in Taiwan. This study aimed to compare the efficacy of the current standard first-line regimen, sequential therapy, with that of vonoprazan-based dual therapy with high-dose Amoxicillin.

Objectives: To compare the efficacy of the current standard first-line regimen, sequential therapy, with that of vonoprazan-based dual therapy, through a randomized controlled trial.

Methods: Patients with H.pylori infection who was over 20 years old and agree to participate in the trial will be recruited. Those who had received H.pylori eradication before, are known to be allergic to any drug used in this trial, are pregnant, or refuse to participate in the trial for any reason will be excluded. We then allocate these patients into two groups randomly - one group receiving vonoprazan-based dual therapy with high-dose amoxicillin (vonoprazan 20 mg + amoxicillin 1000 mg twice daily for fourteen days) and the other receiving extended sequential therapy (lansoprazole 30mg plus amoxicillin 1000mg twice daily for 7 days, followed by lansoprazole 30mg, clarithromycin 500mg, and metronidzole 500mg twice daily for an additional 7 days). Eradication success was evaluated by 13C-urea breath test at least 4 weeks after treatment.

Outcome analysis: The study will be designed as a non-inferiority trial. We anticipate that the two regimens will have comparable efficacy. Besides, we'll also design a questionnaire to evaluate the adverse effects, whether they took the drugs in the right way, and patient's satisfaction of the drug regimen. The vonoprazan dual therapy with high-dose amoxicillin will be anticipated to have fewer adverse effects, better compliance, and better satisfaction.

Background：Helicobacter pylori infection is a well-established risk factor for peptic ulcer disease and gastric cancer. It's now a consensus of experts that H.pylori infection should be treated once it is recognized. Extended proton pump inhibitor (PPI)-based sequential therapy as one of the most commonly used first-line regimens provides a satisfactory eradication rate of 90.7% (95% CI, 87.4% - 94.0%). Nevertheless, its complexity of the "sequential" usage is sometimes confusing to the patients and may lead to treatment failure. The emerging new regimen - vonoprazan-based dual therapy, on the other hand, is another appealing choice with simplicity, and low pill burden. However, there's still no evidence regarding the use of vonoprazan-based dual therapy with high-dose amoxicillin (1000mg twice daily) as the first-line regimen in Taiwan. This study aimed to compare the efficacy of the current standard first-line regimen, sequential therapy, with that of vonoprazan-based dual therapy with high-dose Amoxicillin.

Objectives: To compare the efficacy of the current standard first-line regimen, sequential therapy, with that of vonoprazan-based dual therapy, through a randomized controlled trial.

Methods: Patients with H.pylori infection who was over 20 years old and agree to participate in the trial will be recruited. Those who had received H.pylori eradication before, are known to be allergic to any drug used in this trial, are pregnant, or refuse to participate in the trial for any reason will be excluded. We then allocate these patients into two groups randomly - one group receiving vonoprazan-based dual therapy with high-dose amoxicillin (vonoprazan 20 mg + amoxicillin 1000 mg twice daily for fourteen days) and the other receiving extended sequential therapy (lansoprazole 30mg plus amoxicillin 1000mg twice daily for 7 days, followed by lansoprazole 30mg, clarithromycin 500mg, and metronidzole 500mg twice daily for an additional 7 days). Eradication success was evaluated by 13C-urea breath test at least 4 weeks after treatment.

Outcome analysis: The study will be designed as a non-inferiority trial. We anticipate that the two regimens will have comparable efficacy. Besides, we'll also design a questionnaire to evaluate the adverse effects, whether they took the drugs in the right way, and patient's satisfaction of the drug regimen. The vonoprazan dual therapy with high-dose amoxicillin will be anticipated to have fewer adverse effects, better compliance, and better satisfaction.

Inclusion Criteria:

1. Patients with naive H. pylori infection
2. Subjects with over 20 years old

Exclusion Criteria:

1. Younger than 20 years old
2. Ever received H. eradication therapy
3. ever received total or subtotal gastrectomy in the past
4. Severe chronic disease, such as end stage renal disease, liver cirrhosis, incurable malignant tumors
5. Women who are pregnant or breastfeeding
6. Those who are not suitable to receive study drugs: such as a history of allergies to study drugs or serious side effects, etc.
7. Patient with estimated glomerular filtration rate (eGFR) less than 60 ml/min/1.73 mt2