Potent Acid Suppression With Vonoprazan vs Proton Pump Inhibitors Does Not Have Higher Association With Clostridioides difficile Infection.

INTRODUCTION Proton pump inhibitors (PPIs) are associated with the onset of Clostridioides difficile infection (CDI). Although a new potassium-competitive acid blocker, vonoprazan, consistently shows a more potent acid inhibitory effect in comparison to PPIs, the risk of CDI in vonoprazan-treated patients relative to those treated with PPIs is unknown. In this retrospective case-control study, using a nationwide hospital-based administrative database in Japan, we investigated the association of the onset of CDI in patients treated with vonoprazan. METHODS A CDI case was defined as a case in which a patient was diagnosed and treated for CDI. For each CDI case, 3 non-CDI patients were extracted as controls. Information on the usage of acid suppressants in the 2 months before the onset of CDI and other confounding factors was collected. Relative associations of gastric acid suppressants with the onset of CDI were estimated. RESULTS A total of 4,466 CDI cases and 13,220 of non-CDI controls were extracted. A multivariate conditional regression analysis revealed that PPI or vonoprazan use was modestly, but significantly associated with CDI (odds ratio [95% confidence interval]: PPI, 1.3 [1.2-1.4]; vonoprazan, 1.4 [1.2-1.7]). With PPI users as a reference, vonoprazan did not show a stronger association with CDI (odds ratio [95% confidence interval]: 1.07 [0.91-1.26]). DISCUSSION We found a significant positive association between vonoprazan use and CDI; however, the magnitude of the association was not beyond that in PPI users. This is the first report on any potential adverse effects of vonoprazan.