Aggrenox not affected by co-administration of omeprazole: Study

Boehringer Ingelheim presented results of a drug interaction study that found Aggrenox® (aspirin/extended-release dipyridamole), an antiplatelet medication, is not affected by the co-administration of omeprazole, a proton pump inhibitor (PPI), frequently used to treat several gastrointestinal conditions. These data were presented at the International Stroke Conference (ISC) in New Orleans.

"Omeprazole has been shown to interact with some medications that are metabolized through the CYP2C19 system. AGGRENOX is not metabolized through the CYP2C19 system, however we wanted to understand if it would be affected when given together with omeprazole," said John Smith, MD, PhD, senior vice president for clinical development and medical affairs, Boehringer Ingelheim Pharmaceuticals, Inc. "We are pleased that these data have shown that omperazole does not interact with AGGRENOX."

This multiple-dose, open-label, randomized crossover study was performed in 60 healthy volunteers. The pharmacokinectics of the extended release dipyridamole component of AGGRENOX, and the pharmacodynamics of the aspirin component of AGGRENOX were studied in two dosing sequences: AGGRENOX followed by omeprazole and omeprazole followed by AGGRENOX. The primary endpoints of this study were steady-state maximum concentration (Cmax) and area under the curve (AUC) for the dipyridamole component, as well as the inhibition of platelet aggregation (IPA) by the aspirin component.

The 90 percent confidence intervals of the Cmax and AUC of the dipyridamole component fell within the accepted window of 80 – 125 percent in both dosing sequences indicating no significant interaction. Likewise, no significant effect on IPA was shown with either dosing sequence at four or 12 hours post dose.