6-MONTH ANGIOGRAPHIC AND CLINICAL FOLLOW-UP OF PATIENTS PROSPECTIVELYRANDOMIZED TO RECEIVE EITHER TIROFIBAN OR PLACEBO DURING ANGIOPLASTY IN THE RESTORE TRIAL

Objectives. This study sought to investigate the effects of tirofiban versus placebo on the incidence of adverse cardiac outcomes and corona ry artery restenosis at 6 months. Background. Tirofiban is a highly se lective, short-acting inhibitor of fibrinogen binding to platelet glyc oprotein IIb/IIIa. In a recent clinical study, tirofiban reduced the i ncidence of adverse cardiovascular events at both 2 and 7 days after c oronary angio plasty or directional coronary atherectomy. This reducti on persisted but was no longer statistically significant at 30 days. M ethods. The Randomized Efficacy Study of Tirofiban for Outcomes and Re stenosis (RESTORE) trial was a randomized, double-blind, placebo-contr olled trial of tirofiban in patients undergoing balloon angioplasty or directional atherectomy within 72 h of presentation with either unsta ble angina pectoris or acute myocardial infarction. All patients recei ved an initial bolus (10 mu g/kg body weight over 3 min), followed by a 36-h infusion (0.15 mu g/kg per min) of either tirofiban or placebo. Results. At 6 months the composite end point (either death from any c ause, new myocardial infarction, bypass surgery for angioplasty failur e or recurrent ischemia, repeat target vessel angioplasty or stent ins ertion for actual or threatened abrupt closure) occurred in 1,070 plac ebo group patients (27.1%) and 1,071 tirofiban group patients (24.1%, p = 0.11). Analysis of 6 month coronary arteriograms by means of quant itative coronary arteriography showed no significant difference betwee n placebo- and tirofiban-treated patients in either the incidence of a greater than or equal to 50% diameter stenosis (57% vs. 51%, p = NS), a loss of greater than or equal to 50% of lumen diameter gained (50% vs. 50%, p = NS) or a loss of greater than or equal to 0.72 mm of lume n diameter (44% vs. 42%, p = NS). Conclusions. The 3% absolute reducti on in the incidence of the composite end point at 6 months (27.1% plac ebo vs. 24.1% tirofiban) was similar to that previously reported at 2 days (8.7% vs. 5.1%, p < 0.005), and there does not appear to be any l ate effect of tirofiban on clinical end points between day 2 and 6 mon ths. Tirofiban did not reduce the incidence of restenosis at 6 months when defined in a number of ways. (C) 1998 by the American College of Cardiology.