Acute platelet inhibition with abciximab does not reduce in-stent restenosis.

BACKGROUND Although stents reduce restenosis compared with balloon angioplasty, their long-term efficacy is limited by neointimal hyperplasia. Platelet and alpha(v)beta(3) integrin receptor inhibition limits neointimal proliferation in animal models of arterial injury. METHODS AND RESULTS We tested whether the dual beta(3) integrin blocking agent abciximab, administered for 12 or 24 hours at the same intravenous dose as that shown to reduce adverse clinical events (death, infarction, and revascularization) after angioplasty, would reduce restenotic tissue volume, as measured by intravascular ultrasound at 6 months. Two hundred twenty-five patients were randomly allocated to placebo or abciximab before coronary intervention. Of the 215 patients who received stents and study drug, 191 (88.8%) returned for late (>/=4 months) coronary evaluation. Tissue volume, expressed as a percentage of stent volume, did not differ: 25+/-15%, 27+/-15%, and 29+/-14% for the patients in the placebo and the 12- and 24-hour abciximab groups, respectively. Lack of abciximab benefit was confirmed by quantitative coronary angiography (dichotomous restenosis: 11.6%, 18. 9%, and 19.4%; loss index: 0.33, 0.52, and 0.47, respectively, P=NS). CONCLUSIONS Potent platelet inhibition with abciximab, as administered in this study, does not reduce in-stent restenosis. The interrelationship between stents, platelets, and neointimal proliferation requires further study.