Comparison of Vonoprazan and Low-Dose Amoxicillin Dual Therapy with Bismuth-Containing Quadruple Therapy for Naïve Helicobacter pylori Eradication: A Single-Center, Open-Label, Randomized Control Trial

Abstract

Objective: This study aimed to compare the effectiveness and safety of vonoprazan-amoxicillin (VA) dual therapy with modified bismuth-containing quadruple therapy (esomeprazole, bismuth, amoxicillin, and clarithromycin; EBAC) in treatment-naïve patients infected with Helicobacter pylori (H. pylori).

Methods: In this single-center, open-label, randomized controlled trial conducted from July to December 2024, a total of 504 H. pylori-positive patients were randomly allocated to receive either VA (vonoprazan 20 mg and amoxicillin 1000 mg, twice daily for 14 days) or EBAC (esomeprazole 20 mg bid, bismuth potassium citrate 220 mg bid, amoxicillin 1000 mg bid, clarithromycin 500 mg bid, twice daily for 14 days). The primary endpoint was the H. pylori eradication rate, and the secondary endpoint was safety.

Results: In the intention-to-treat (ITT) analysis, the eradication rates were 79.4% (200/252) in the VA group and 85.7% (216/252) in the EBAC group (p = 0.060). Per-protocol (PP) analysis showed comparable eradication rates between the two groups (92.1% [197/214] vs. 93.0% [213/229], p = 0.712), confirming the non-inferiority of VA compared to EBAC. The incidence of adverse events was significantly fewer in the VA group (27.2% vs. 42.7%, p < 0.001). Logistic regression identified medication adherence (≥80%) as the only independent predictor of successful eradication (OR 17.557, p < 0.001).

Conclusions: VA dual therapy achieved comparable H. pylori eradication rates to EBAC, while offering better safety and a more convenient regimen, supporting it as a preferred first-line treatment for H. pylori infection.

Keywords: Helicobacter pylori; amoxicillin; dual therapy; proton pump inhibitors; quadruple therapy; vonoprazan.

Figure 1

Flow chart of patient grouping. EBAC, esomeprazole, bismuth, amoxicillin, and clarithromycin; VA, vonoprazan, amoxicillin; ITT, intention-to-treat; mITT, modified intention-to-treat; PP, per-protocol.