Which antiplatelet drug is best for patients on PPIs? New trial to the rescue
A Paris-based clinical trial will set out to determine the efficacy of two antiplatelet drugs, prasugrel (Effient, Daiichi-Sankyo/Eli Lilly) or a double dose of clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi Aventis), in coronary artery disease patients who are taking lansoprazole (Prevacid, Takeda), a proton-pump inhibitor (PPI).

The study will split 104 patients into two arms: one will be administered 150 mg of clopidogrel (double dose) and the other arm will be administered prasugrel. The patients in each group will be administered either a placebo or lansoprazole. The researchers will then decipher whether  lansoprazole is less likely to impair the efficacy of the antiplatelet drugs than other PPIs that have been shown to raise the risk of major cardiovascular events (MACE) and weaken the benefits of clopidogrel.

Researchers from the Hospital Pitie’ Salpetriere’ in France will record patient data at baseline and at two weeks after they received lansoprazole. Additionally, they will determine whether a patient can properly metabolize clopidogrel in the active form by testing and studying the patient’s genetic makeup.

"What we already know is that the benefits of Plavix can be blunted either by genetics or the use of second drugs like a proton-pump inhibitor," said Robert S. Epstein, MD, chief medical officer and president of Medco Health Solutions, which is sponsoring the study.  "What we hope to learn from this study is whether you can avoid this problem through double dosing Plavix or whether you need to move on to newer drugs like Effient. This is important from both a clinical and economic standpoint as health systems around the world are struggling with the issues of cost and quality of care."

A previous CMOS (Clopidogrel Medco Outcomes Study) trial conducted by Medco found that clopidogrel, in conjunction with any PPI, increased the risk of hospitalization and cardiovascular events in patients by 51 percent.

“The [current] study will examine whether the 70 to 75 percent of patients who are 'extensive metabolizers' of clopidogrel – because they were born with a normally functioning version of the CYP2C19 gene – have comparable outcomes to those patients taking prasugrel,” said the Paris-based company.

Medco expects results of the study to be available in 2012.