• Cardiology Clinical Trials
• Myocardial Infarction
• Interventional Techniques & Devices

Michelle O'Donoghue, MD, Brigham and Women's Hospital, Boston, MA, reported the results of an analysis of data from a subgroup of patients in the TRITON-TIMI 38 study [NCT00097591; Wiviott et al. N Engl J Med 2007] who were receiving proton pump inhibitor (PPI) therapy in addition to a thienopyridine (prasugrel or clopidogrel). The results showed no association between PPI use and an increased risk of cardiovascular (CV) events [O'Donoghue M et al. Lancet 2009].

The TRITON-TIMI 38 trial randomized 13,608 subjects with acute coronary syndrome (ACS) and planned percutaneous coronary intervention (PCI) to prasugrel or clopidogrel, in addition to standard therapy. The use of a PPI was at the discretion of the treating physician and was captured on the case report forms. The primary outcome of the study was CV events (defined as CV death, myocardial infarction [MI], or stroke).

At randomization, 4529 (33%) of the subjects were being treated with a PPI. The most frequently used PPIs were pantoprazole (40%) and omeprazole (37%). Subjects who were on a PPI were slightly older than those who were not on a PPI (median age 61 vs 60 years) and were more likely to be women. The PPI group was also more likely to be white, be enrolled at a center in Western Europe or North America, have a history of peptic ulcer disease or lower baseline hemoglobin (all p<0.001), or have an index diagnosis of unstable angina or non-ST-segment MI (p=0.007).

There was no association between the use of a PPI and an increase in the primary endpoint of a major CV event for either clopidogrel or prasugrel (Table 1).

Similarly, the use of a PPI was not associated with an increased risk of MI, stent thrombosis, or urgent revascularization or a decreased risk of bleeding for patients who were treated with either clopidogrel or prasugrel. Sensitivity analyses demonstrated consistency of the results based on consistency of PPI use (ie, subjects on PPIs at both randomization and at study end), different types of PPIs, and varying durations of follow-up.

Dr. O'Donoghue noted that interpretation of these results may be limited by the fact that use of a PPI was not randomized; thus, there is the potential for residual confounding. In addition, PPIs could be started or stopped during the course of follow-up. She concluded, “Although only a randomized trial of a PPI can definitively establish the safety of combining these two classes of drugs, the current findings do not support the need to avoid concomitant use of PPIs in patients treated with thienopyridines.”

• © 2009 MD Conference Express