Aug. 31, 2009 -- Heart patients who take the anti-clotting drug Plavix may safely take an acid-reducing proton pump inhibitor (PPI) drug, an analysis of two previously reported studies suggests.
The new findings seem to contradict several recent studies showing negative outcomes in heart patients who took Plavix with a PPI, especially the drug Prilosec.
Plavix and another anti-clotting drug, Effient, which was approved by the FDA in June, are prescribed to heart attack patients along with aspirin to prevent blood clots that can cause a second heart attack or stroke.
PPIs OK With Plavix
The new analysis showed no increase in heart attack, stroke, or cardiovascular death risk in patients taking PPIs while also taking Plavix or Effient.
“We did not find use of a PPI to be associated with a higher risk of cardiovascular events for patients taking either of these drugs,” lead researcher Michelle L. O’Donoghue, MD, of Boston’s Brigham and Women’s Hospital, tells WebMD. “This raises the question as to why the current findings differ from those of prior analyses.”
One theory is that PPIs may be prescribed most often to the sickest heart attack patients, he says.
The studies included in the analysis were sponsored by Effient manufacturer Eli Lilly & Co. and were designed to compare the drug to Plavix.
The larger of the two trials included about 13,600 patients who had a previous heart attack or unstable angina treated with one of the two drugs.
“This may help explain why patients on a PPI seem to do more poorly than other patients in many studies,” O’Donoghue says.
One-third of the patients in the trial were also taking a PPI, but PPI use was not found to be associated with an increased risk of a second heart attack, stroke, or cardiovascular death with either of the two anti-clotting drugs.
PPIs Not Appropriate for All
The study appears online Tuesday and is scheduled for publication in an upcoming issue of the journal The Lancet.
"The current findings provide some reassurance to clinicians that PPIs and [the anti-clotting drugs] can be safely combined in patients for whom there is a strong indication to use both drugs,” O’Donoghue says.
But PPIs should not be given to all patients taking Plavix or Effient, researcher Dirk Sibbing tells WebMD.
In an editorial published with the study, Sibbing writes that PPI use may be especially risky for a subpopulation of heart patients that’s genetically predisposed to have a reduced response to the anti-clotting drugs.
Heart surgeon Timothy J. Gardner, MD, who is immediate past-president of the American Heart Association, tells WebMD more study is needed to fully understand impact of PPIs on Plavix in heart patients.
In late January, the FDA announced that Plavix manufacturers Bristol-Myers Squibb and Sanofi-Aventis had agreed to conduct such studies.
Gardner says patients taking Plavix or Effient with a PPI need to be monitored carefully by their prescribing physician.