ReoPro shown to reduce post-stent AMIs

Drug boosts safety of stenting and angioplasty

Researchers have shown that use of abciximab (Malvern, PA-based Centocor’s ReoPro) substantially improves the safety of coronary stenting procedures and that balloon angioplasty with abciximab is safer than stenting without the agent.1 The study authors state that their trial provides strong evidence that the armamentarium of heparin, aspirin, and ticlopidine is insufficient and that a decrease of more than 50% in major events can be achieved with abciximab. The agent, they say, represents "a new standard of care for prevention of major adverse ischemic outcomes." Although the agent costs approximately $1,500 per dose, those are "strong words to show your hospital administrator," states Michael H. Crawford, MD, chief of cardiology at the University of New Mexico in Albuquerque.

Inhibition of the platelet glycoprotein-IIb/IIIa receptor (IIb/IIIa) for reduced clotting had been shown to improve revascularization when used in combination with balloon angioplasty. Investi-gators for the largest coronary stent trial to date, the EPISTENT (Evaluation of IIb/IIIa Platelet Inhibitor for Stenting) study, wanted to find out whether a IIb/IIIa inhibitor would be beneficial when combined with stenting.

At 63 hospitals in the United States and Canada, more than 2,000 patients with heart disease were randomly assigned to three groups: stenting plus placebo, stenting plus the drug abciximab, or balloon angioplasty plus abciximab. All patients received aspirin and heparin. The researchers wanted to find out how these different methods affected the likelihood of death, nonfatal acute myocardial infarctions (AMI), or the need for urgent revascularization in the first 30 days after treatment.

There were fewer deaths and AMIs in the stent group receiving abciximab than in the group that did not. Of the patients who received stenting plus placebo, nearly 11% died, had a nonfatal AMI, or needed urgent revascularization. The result was the same for only about 7% of the patients given balloon angioplasty plus abciximab and only 5.3% of those assigned stenting plus abciximab.

Both death and major AMI occurred less with the use of abciximab — 7.8% in the placebo group, 4.7% for balloon angioplasty plus abciximab, and 3% for stenting plus abciximab. Researchers concluded that use of abciximab substantially improved the safety of stenting procedures and that balloon angioplasty with abciximab is safer than stenting without abciximab.

One difficulty for all types of catheter-based revascularization strategies has been the need for repeat revascularization procedures in the target vessel within six months. The endpoint of death, AMI, or urgent target vessel revascularization within six months was significantly reduced from more than 18% in the placebo and stent group to 13.0% in the abciximab and stent group.

Among diabetics, who tend to have worse outcomes after coronary revascularization procedures, the composite endpoint of death, AMI, or target vessel revascularization was reduced by half, suggesting the combined use of abciximab and stents can substantially mitigate the higher risk and poorer long-term outcomes of coronary interventions in diabetics — a major step in the treatment of ischemic heart disease in this population.

The most common side effect of abciximab is bleeding. However, the EPISTENT study showed that bleeding events can be reduced to a level similar to placebo by using low-dose, weight-adjusted heparin regimens, early sheath removal, and meticulous care of the site of catheter insertion.

Reference

1. The EPISTENT Investigators. Randomized placebo-controlled and balloon-angioplasty-controlled trial to assess safety of coronary stenting with use of platelet glycoprotein-IIb/IIIa blockade. Lancet 1998;352:87-92.