Vonoprazan-amoxicillin dual therapy with different amoxicillin dosages for treatment-naive patients of Helicobacter pylori infection in China: a prospective, randomized controlled study.

Background: The vonoprazan (VPZ)-amoxicillin (AMO) dual therapy (VA) demonstrates a satisfactory eradication rate for Helicobacter pylori (H. pylori ). However, the optimal dosage of AMO in this regimen remains uncertain. The objective of this study is to investigate the efficacy of different doses of AMO in the VA regimen for first-line treatment of H. pylori infection.

Methods: A total of 192 treatment-naive H. pylori -infected patients were randomly assigned to one of three groups: low-dose VA (LD-VA: VPZ 20 mg b.i.d + AMO 750 mg t.i.d), moderate-dose VA (MD-VA:VPZ 20 mg b.i.d + AMO 1000 mg t.i.d), and high-dose VA (HD-VA: VPZ 20 mg b.i.d + AMO 1250 mg t.i.d). All groups received 14 days of treatment. The study evaluated and compared the eradication rates, adverse events (AEs), and patient compliance among the three groups.

Results: Eradication rates for LD-VA, MD-VA, and HD-VA were 76.6% (49/64), 79.7% (51/64), and 84.4% (54/64), respectively, as determined by intention-to-treat analysis; 90.6% (48/53), 94.3% (50/53), and 98.1% (53/54) according to per-protocol analysis; 89.1% (49/55), 94.4% (51/54), and 96.4% (54/56) with modified intention-to-treat analysis (all P  > 0.05). Although not statistically significant, numerically higher eradication rates were observed with the higher dose AMO VA regimen. There were no statistically significant differences in the incidence of AEs and compliance among the three VA regimens.

Conclusion: Fourteen-day VA regimens with AMO doses exceeding 2 g/day demonstrated satisfactory eradication rates. HD-VA therapy is potentially the most effective regimen. Large-sample clinical trials are required to further validate these findings.