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.