Use of prasugrel for antiplatelet therapy growing steadily, study says


April 30, 2014 – Prasugrel is most frequently used in low-risk heart attack patients, despite evidence suggesting it could be of greater benefit to high-risk patients.

There has been a modest but steady increase in the use of prasugrel in antiplatelet therapy for heart attack patients, according to a recent study by DCRI researchers. The researchers also found that prasugrel is most frequently utilized in the lowest‐risk patients, despite evidence suggesting it could be of greater benefit to higher‐risk patients.

The study, by the DCRI’s Matthew Sherwood, MD (pictured); Andrew Peng, MS; Matthew Roe, MD, MHS; Eric Peterson, MD, MPH; and Tracy Wang, MD, MHS, MSc; and colleagues from Massachusetts and Texas, was published this month in the Journal of the American Heart Association.

matthew-sherwood-newsCurrent American College of Cardiology/American Heart Association guidelines recommend the initiation of dual antiplatelet therapy as soon as possible for heart attack patients. Earlier research suggests that treatment with aspirin and a P2Y12 antagonist improves outcomes in patients with ST-segment elevation myocardial infarction (STEMI) as well as those with non-ST-segment elevation myocardial infarction (NSTEMI). Most of these studies, however, involved clopidogrel. Since then, newer P2Y12 antagonists such as prasugrel have become available to cardiac patients. In this study, Sherwood and his colleagues sought to examine patterns of antiplatelet management practices since the introduction of these newer therapies.

Using data from the ACTION Registry/Get With the Guidelines, the researchers evaluated the patterns of P2Y12 antagonist use within 24 hours of admission in 100,228 STEMI patients and 158,492 NSTEMI patients in 548 U.S. hospitals between October 2009 and September 2012. They found that prasugrel use increased significantly from 2009-2012, jumping from 3 percent to 18 percent (5 to 30 percent in STEMI patients and 2 to 10 percent in NSTEMI patients). In addition to the increase in prasugrel use, there was an observed decrease in early P2Y12 antagonist use but not discharge use among NSTEMI patients. In both STEMI and NSTEMI patients, prasugrel was most frequently used in patients at the lowest predicted risk for bleeding and mortality, and despite a lack of supporting evidence, prasugrel was initiated before cardiac catheterization in 18 percent of NSTEMI patients.

Three percent of patients with prior stroke received prasugrel, despite being contraindicated. The drug was also used in 1.9 percent of patients 75 years or older and in 4.5 percent of patients with weight below 60 kg, groups for which the FDA advised cautionary use.

“We were surprised to find that doctors were prescribing prasugrel for these patients,” Sherwood said. “It’s possible that some doctors don’t fully understand the dangers.”

Sherwood and his colleagues concluded that opportunities exist to improve risk stratification of heart attack patients and to better target potent antiplatelet therapy to those most likely to benefit, preventing inappropriate use in patients with contraindications or at high risk of bleeding.

“Most of the patterns we saw were positive, but there’s room for improvement in how doctors prescribe these drugs,” he said.