Efficacy of Vonoprazan-Based Triple Therapy with Sitafloxacin and Amoxicillin for Third-Line Helicobacter pylori Eradication: A Multicenter Prospective Analysis on Drug Resistance and gyrA Mutations.

Introduction: Vonoprazan (VPZ) is a potent gastric acid secretion inhibitor used to improve the outcomes of Helicobacter pylori (H. pylori) eradication treatments. However, the increasing prevalence of antibiotic-resistant H. pylori strains has limited the efficacy of H. pylori eradication therapies. The aim of this study was to evaluate the efficacy and safety of a 7-day triple therapy with VPZ, amoxicillin (AMOX), and sitafloxacin (STFX) as a third-line H. pylori eradication treatment.

Methods: Patients in whom second-line eradication therapy failed were enrolled. The minimum inhibitory concentrations of STFX and AMOX, as well as the gyrA mutation status of H. pylori strains, were determined before treatment. The patients received VPZ (20 mg) twice daily, AMOX (500 mg) four times daily, and STFX (100 mg) twice daily for 7 days (vonoprazan-amoxicillin-sitafloxacin [VAS] group). Successful eradication was evaluated using the 13C-urea breath test.

Results: Of the 114 patients enrolled, 75 were treated with the VAS regimen. The overall eradication rate in the VAS group was 90.7% and 94.4% in the intention-to-treat and per-protocol populations, respectively. The VAS regimen completely eradicated gyrA mutation-negative H. pylori strains. Furthermore, it eradicated all strains containing gyrA mutations at position D91. Adverse events were observed in 38.7% of patients, and treatment was discontinued in 1 patient because of eruption, diarrhea, and headache.

Conclusion: Overall, the 7-day VAS regimen exhibited an excellent safety profile and efficacy as a third-line eradication treatment, even against gyrA mutation-positive H. pylori strains.