Susceptibility-Guided Triple Therapy Achieves High Helicobacter pylori Eradication Regardless of Duration

Although clarithromycin resistance is a major cause of empirical triple therapy failure for Helicobacter pylori eradication, the clinical relevance of amoxicillin susceptibility remains uncertain. We first compared eradication outcomes between empirical and susceptibility-guided tailored triple therapy and then evaluated the influence of treatment duration and amoxicillin susceptibility among patients with clarithromycin-susceptible strains receiving tailored triple therapy.

We retrospectively analyzed 807 patients receiving empirical or susceptibility-guided tailored triple therapy in Korea from 2020 to 2024. Eradication outcomes were assessed in modified intention-to-treat (mITT) and per-protocol (PP) populations by antibiotic susceptibility and treatment duration.

Eradication rates were higher with tailored than empirical triple therapy (mITT: 92.9% vs. 69.3%, p < 0.001; PP: 93.7% vs. 69.7%, p < 0.001). Among patients with clarithromycin-susceptible strains receiving tailored triple therapy, eradication rates were higher in amoxicillin-susceptible than in amoxicillin-resistant strains in the mITT analysis (94.0% vs. 86.8%, p = 0.034), whereas the difference was not statistically significant in the PP analysis (94.5% vs. 89.4%, p = 0.118). In the PP population, eradication rates did not differ significantly according to treatment duration in either amoxicillin-susceptible (p = 0.073) or amoxicillin-resistant strains (p = 0.884).

Among patients with clarithromycin-susceptible strains receiving tailored triple therapy, eradication rates did not differ significantly according to treatment duration. However, these findings should be interpreted cautiously because the study may have been underpowered to detect modest but clinically meaningful differences. Amoxicillin susceptibility may be associated with eradication outcomes, although the statistical robustness of this association remains limited.