Randomised clinical trial: efficacy and safety of H. pylori eradication treatment with and without Saccharomyces boulardii supplementation.

Background: Standard triple therapy is commonly prescribed Helicobacter pylori eradication regimen in Europe. However, the world is witnessing declines in eradication success. It is crucial to find better treatment options.

Aims: To evaluate efficacy, compliance and side effects of H. pylori eradication treatment by adding Saccharomyces boulardii .

Methods: We conducted a randomized clinical trial within the GISTAR cohort, consisting of healthy individuals aged 40-64 years. Participants were administered clarithromycin-containing triple therapy (clarithromycin 500 mg, amoxicillin 1000 mg, esomeprazole 40 mg) twice daily. Randomization was applied based on two factors: 1)addition of Saccharomyces boulardii CNCM I-745 500 mg BID or not; 2)treatment duration of 10 or 14 days. Treatment completion and adverse events were assessed via telephone interview 21-28 days after medication delivery. The efficacy was evaluated using a 13C-urea breath test (UBT) six months after treatment.

Results: Altogether 404 participants were enrolled; data on adverse events were available from 391. Overall, 286 participants received follow-up UBT. Intention-to-treat analysis revealed higher eradication rates for 10-day probiotic treatment (70.8% vs. 54.6%, P  = 0.022), but not for 14-day. Probiotic subgroups combined showed non-significantly higher efficacy in per-protocol analysis (90.6% vs. 85.0%, P  = 0.183). S. boulardii reduced the frequency of adverse events ( P  = 0.033) in 14-day regimen, particularly treatment-associated diarrhea ( P  = 0.032). However, after the adjustment to control Type I error, results lost their significance.

Conclusion: Addition of S. boulardii to 14-day clarithromycin-containing triple regimen non-significantly lowers the likelihood of diarrhea and does not increase the eradication rate.