High Dose Tirofiban is similar to Abciximab in reducing Major Adverse Cardiac Events

March 30, 2008 By Alexandra M. Palmer [mailto:apalmer@perfuse.org]

SCAI-ACCi2 08-Chicago, IL: The Multistrategy study demonstrates that high dose tirofiban is non-inferior to abciximab during primary PCI for acute myocardial infarction. Placement of Sirolimus eluting stents were associated with a significant reduction in major adverse cardiac events when compared to bare metal stents. The data was presented by Dr. Marco Valgimigli at the at the SCAI-ACC i2 summit Annual Scientific Sessions in Chicago today.

The goal of this trial was to evaluate the risks and benefits of administering tirofiban at high bolus dose (25μg/Kg over 3 minutes) followed by a standard infusion rate vs abciximab. In addition, the study set out to assess the efficacy of drug-eluting stents in the setting of ST elevation MI. In the comparison of tirofiban and abciximab, the primary endpoint was the incidence of a ≥50% reduction in ST segment elevation. In the stent arm the primary endpoint consisted of major adverse cardiac events (MACE) which included death, reinfarction and target vessel revascularization at 8 months.

The study enrolled 745 STEMI patients at 16 centers. Patients were randomized to 4 different arms: Abciximab and bare metal stent-BMS (n=186), abciximab and sirolimus-eluting stent (n=187), tirofiban and bare metal stent (n=186), and tirofiban and sirolimus-eluting stent (n=186).

There was no significant difference in % ST segment resolution between the tirofiban and the abciximab groups [n=722, 85.3% vs. 83.6%, (95% CI, 0.958-1.086)]. There was also no significant difference in the incidence of the efficacy endpoints such as MACE (p=0.85), death/MI (p=0.98), urgent target vessel revascularization (p=0.59), and stent thrombosis (definite, p=0.56) at 30 days and at 8 months (overall MACE 9.8% vs. 12.4%, p=0.3) between tirofiban and abciximab. However, thrombocytopenia was more prevalent among patients treated with abciximab as compared to those treated with tirofiban (4.0% vs. 0.8%, p=0.004) with no difference in major bleeding (p=0.44).

Placement of Sirolimus stents compared with BMS was associated with significant reduction in the occurrence of MACE [7.8% vs. 14.5%, HR 0.53 (97.5% CI 0.33-0.83), p=0.006] at 8 months following primary PCI with no increase in the occurrence of stent thrombosis (definite, p=0.65).

Investigators conclude that among patients with ST elevation MI, high dose tirofiban administration is associated with non-inferior ST-segment resolution at 90 minutes when compared with abciximab. There was also no difference in the 30 day efficacy MACE between tirofiban and abciximab.