The effect of esomeprazole vs famotidine on aspirin/clopidogrel dual therapy after percutaneous coronary intervention.

Background: Regarding drug interactions between proton pump inhibitors (PPIs) and dual antiplatelet therapy (DAPT), controversies have arisen over the possibility that PPIs may interfere with the antiplatelet effect of DAPT. However, whether this interaction is drug-specific or a class effect needs to be determined. It is not clear whether famotidine, an H2-receptor antagonist (H2RA), interacts with DAPT.

Objectives: The aim of this study was to assess the impact of esomeprazole and famotidine on the efficacy of DAPT.

Material And Methods: The study involved 160 patients undergoing elective percutaneous coronary interventions and treated with DAPT and concomitant use of esomeprazole (40 mg/d) or famotidine (40 mg/d). Platelet reactivity was measured with adenosine diphosphate (ADP)-induced light transmittance aggregometry (LTA) and vasodilator-stimulated phosphoprotein phosphorylation-platelet reactivity index (VASP-PRI) at baseline, 14 and 30 days after applying randomized acid-suppressing agents.

Results: No significance differences were observed in treatment-by-period interactions with LTA values (p = 0.298) and VASP-PRI values (p = 0.867), which suggested no carryover effect in either regimen over the 30-day treatment period. Intergroup comparisons were done between the 2 groups at 3 times, and similar findings were observed at each time (all p > 0.05). As for intragroup measurements among the separate times, significantly lower LTA and VASP-PRI values existed on day 14 for both agents (both p < 0.05).

Conclusions: The antiplatelet effect of DAPT was not affected by concomitant use of esomeprazole or famotidine. These 2 agents were much less likely than CYP2C19 polymorphisms to influence aspirin/clopidogrel therapy, supporting the assertion that the pharmacodynamic interaction between aspirin/clopidogrel and acid-suppressing agents is a drug-specific rather than a class effect.