Pharmacokinetics, Safety, and Tolerability of Vonoprazan- or Esomeprazole-Based Bismuth-Containing Quadruple Therapy: A Phase 1, Double-Blind, Parallel-Group Study in Adults with Helicobacter pylori Infection in China

Quadruple therapy comprising 2 antibiotics, a proton pump inhibitor, and bismuth, is recommended for Helicobacter pylori eradication in China. This Phase 1, double-blind, parallel-group study aimed to evaluate the pharmacokinetics, safety, and tolerability of bismuth-containing vonoprazan- or esomeprazole-based quadruple therapy in H. pylori-positive healthy subjects at a single site in China. Quadruple therapy comprising vonoprazan 20 mg or esomeprazole 20 mg with bismuth potassium citrate 600 mg (equivalent to bismuth 220 mg), clarithromycin 500 mg, and amoxicillin 1000 mg was administered twice daily for 2 weeks. Forty-four subjects were enrolled, 22 each in the vonoprazan (mean age, 34.5 years; men, 63.6%) and esomeprazole (mean age, 31.6 years; men, 59.1%) groups. Day 14 bismuth plasma pharmacokinetic parameters area under the plasma concentration-time curve during a dosing interval (geometric mean ratio, 1.07 [90% confidence interval, 0.82-1.40]) and maximum observed plasma concentration (geometric mean ratio, 1.30 [90% confidence interval, 0.94-1.81]) were similar between the treatment groups. At Day 42 follow-up, 100% and 94.4% of subjects were H. pylori negative in the vonoprazan and esomeprazole groups, respectively. The incidence of treatment-emergent adverse events was similar between the groups, with no serious adverse events. No new safety concerns were identified. In conclusion, vonoprazan had no significant effect on plasma bismuth exposure compared with esomeprazole.