METHODS: We performed a 3 × 2 partial factorial double-blind trial of 17,598 participants with stable cardiovascular disease and peripheral artery disease. Participants were randomly assigned to groups given pantoprazole 40 mg daily or placebo, as well as rivaroxaban 2.5 mg twice daily with aspirin 100 mg once daily, rivaroxaban 5 mg twice daily, or aspirin 100 mg alone. The primary outcome was time to first upper gastrointestinal event, defined as a composite of overt bleeding, upper gastrointestinal bleeding from a gastroduodenal lesion or of unknown origin, occult bleeding, symptomatic gastroduodenal ulcer or ≥5 erosions, upper gastrointestinal obstruction, or perforation.

RESULTS: There was no significant difference in upper gastrointestinal events between the pantoprazole group (102 of 8791 events) and the placebo group (116 of 8807 events) (hazard ratio, 0.88; 95% confidence interval [CI], 0.67-1.15). Pantoprazole significantly reduced bleeding of gastroduodenal lesions (hazard ratio, 0.52; 95% confidence interval, 0.28-0.94; P = .03); this reduction was greater when we used a post-hoc definition of bleeding gastroduodenal lesion (hazard ratio, 0.45; 95% confidence interval, 0.27-0.74), although the number needed to treat still was high (n = 982; 95% confidence interval, 609-2528).