Safety and effectiveness of vonoprazan-based rescue therapy for infection.

Background: Vonoprazan (VPZ)-based regimens are an effective first-line therapy for () infection. However, their value as a rescue therapy needs to be explored.

Aim: To assess a VPZ-based regimen as rescue therapy.

Methods: This prospective, single-center, clinical trial was conducted between January and August 2022. Patients with a history of treatment failure were administered 20 mg VPZ twice daily, 750 mg amoxicillin 3 times daily, and 250 mg () twice daily for 14 d (14-d VAS regimen). VPZ and were taken before meals, while amoxicillin was taken after meals. Within 3 d after the end of eradication therapy, all patients were asked to fill in a questionnaire to assess any adverse events they may have experienced. At least 4-6 wk after the end of eradication therapy, eradication success was assessed using a C-urea breath test, and factors associated with eradication success were explored.

Results: Herein, 103 patients were assessed, and 68 patients were finally included. All included patients had 1-3 previous eradication failures. The overall eradication rates calculated using intention-to-treat and per-protocol analyses were 92.6% (63/68) and 92.3% (60/65), respectively. The eradication rate did not differ with the number of treatment failures ( = 0.433). The rates of clarithromycin, metronidazole, and levofloxacin resistance were 91.3% (21/23), 100.0% (23/23), and 60.9% (14/23), respectively. There were no cases of resistance to tetracycline, amoxicillin, or furazolidone. In 60.9% (14/23) patients, the isolate was resistant to all 3 antibiotics (clarithromycin, metronidazole, and levofloxacin); however, eradication was achieved in 92.9% (13/14) patients. All patients showed metronidazole resistance, and had an eradication rate of 91.3% (21/23). The eradication rate was higher among patients without anxiety (96.8%) than among patients with anxiety (60.0%, = 0.025). No severe adverse events occurred; most adverse events were mild and disappeared without intervention. Good compliance was seen in 95.6% (65/68) patients. Serological examination showed no significant changes in liver and kidney function.

Conclusion: VAS is a safe and effective rescue therapy, with an acceptable eradication rate (> 90%), regardless of the number of prior treatment failures. Anxiety may be associated with eradication failure.