In this small randomized pilot study of PCI patients, both tegoprazan (a P-CAB) and pantoprazole (a PPI) were associated with modest within-arm gut microbiome changes over 24 weeks, but no treatment group-by-visit interaction was significant, so the taxon-level findings are exploratory and hypothesis-generating rather than evidence of treatment-specific effects.
No drug-related adverse events or gastrointestinal bleeding occurred in any group during 24 weeks of follow-up.
Only 24 of the 38 randomized participants were included in the final analysis because of missing baseline samples and dropout.
Observed ASV richness was significantly higher at week 24 than at baseline in the overall cohort and in the P-CAB group, while the Shannon index did not change significantly.
Within-arm Bray-Curtis beta diversity differed significantly between baseline and week 24 in the P-CAB and PPI groups but not in the no acid-suppressive therapy group.
The formal cross-arm test of treatment group-by-visit interaction for Bray-Curtis beta diversity was not significant.
Nominal within-arm taxonomic changes were observed, but no treatment group-by-visit interaction for any taxon survived Benjamini-Hochberg correction in ANCOM-BC2.
Both acid-suppressive treatments were associated with modest longitudinal microbiome changes, and larger adequately powered studies are needed.
This small pilot study looked at whether two types of stomach-acid-lowering drugs, tegoprazan (a newer potassium-competitive acid blocker) and pantoprazole (a standard proton pump inhibitor), change the bacteria living in the gut. Participants were people with angina who had a heart stent procedure (PCI) and needed blood-thinning treatment. They were randomly given one of the drugs or no acid-suppressing drug for 24 weeks, and stool samples were analyzed before and after. Both drug groups showed modest changes in gut bacterial makeup over time, while the no-drug group did not. Tegoprazan was also linked to an increase in the number of distinct bacterial variants. However, when the researchers directly compared the groups with each other, the differences in how the microbiome changed were not statistically significant. No drug-related side effects or gastrointestinal bleeding were seen in any group. This research suggests that tegoprazan is tolerated over 24 weeks and that both acid-suppressing drugs may be associated with small gut microbiome shifts, but it does not show that one drug affects the microbiome differently from the other. Only 24 people were analyzed, so the findings are preliminary. Larger studies are needed to confirm whether the drugs really differ in their effects on gut bacteria.
Lee S, Na S, Park S, Cho B, Lee B, Cho Y, et al.. (2026). Effect of a potassium-competitive acid blocker on the gut microbiota in patients undergoing percutaneous coronary intervention: a randomized pilot study.. Frontiers in cellular and infection microbiology. https://doi.org/10.3389/fcimb.2026.1942212