Long-term, three-year, mortality data was presented from the Phase III, open label, multinational study comparing high-dose bolus ( HDB ) dosing of Tirofiban ( Aggrastat ) ( 25mcg/kg bolus followed by a 0.15mcg/kg/min infusion for 18-24 hours ) versus Abciximab ( ReoPro ) in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction ( STEMI ), at the 2010 European Society of Cardiology Meeting in Stockholm, Sweden.

At three years, all but nine patients were available for clinical follow-up ( n=745 ). Patients receiving HDB dosing of Tirofiban had comparable rates of all-cause ( 6.7% versus 7.8%; P=0.56 ) and adjudicated cardiac-related ( 4.8% versus 6.5%, P=0.33 ) mortality when compared to Abciximab treated patients.
All-cause death or myocardial infarction was similar in both treatment groups ( 12.9% versus 12.9% ).

As previously published in JAMA ( 2008 ) at least 50 percent recovery from ST-elevation occurred in 85.3% and 83.6% of patients in the HDB Tirofiban and Abciximab groups, respectively ( relative risk, RR=1,020; P<0.001 for non-inferiority ).
At 30 days, ischemic and hemorrhagic outcomes were similar in the HDB Tirofiban and Abciximab groups, with the incidence of thrombocytopenia being significantly more common with Abciximab compared to HDB Tirofiban ( 4% versus 0.8%, P=0.004 ).
At 8 months, the incidence of major adverse cardiac events ( MACE ) was approximately 20% lower in patients treated with HDB Tirofiban compared to Abciximab ( 9.8% versus 12.4%; P=0.30 ).

The three-year results of the MULTISTRATEGY trial have demonstrated that in STEMI patients undergoing primary PCI, treatment with Tirofiban results in similar clinical outcomes with improved safety, in terms of lower thrombocytopenia, and lower-costs relative to Abciximab.

The MULTISTRATEGY trial of 745 patients presenting with STEMI or new left bundle-branch block was conducted in 16 referral Centers in Italy, Spain and Argentina from October 2004 to April 2007. Patients were randomly assigned with the use of a 2-by-2 factorial design to one of four interventional strategies: Abciximab with an uncoated-stent, Abciximab with a Sirolimus-eluting stent, Tirofiban with an uncoated-stent, or Tirofiban with a Sirolimus-eluting stent.

The study’s primary end points included evaluating Tirofiban’s noninferiority to Abciximab for cumulative ST-segment resolution, expressed as the proportion of patients that achieve at least 50% recovery within 90 minutes after intervention, as well as whether the Sirolimus-stent is superior to uncoated-stent in terms of the composite of death from any cause, reinfarction and clinically-driven target vessel revascularization within the first 8 months, at 1 year, 3 years and 5 years. Secondary endpoints included each component of the composite end point, stent thrombosis and bleedings according to the criteria of the Thrombolysis in Myocardial Infarction ( TIMI ) trials.

Either Tirofiban or Abciximab was administered at first medical contact, before arterial sheath insertion. Tirofiban was given as a bolus of 25 microg/kg, followed by an 18-24 hour infusion at 0.15 microg/kg/min. Abciximab was administered as a bolus of 0.25 mg/kg, followed by a 12-hour infusion at 0.125 microg/kg/min.
Stenting, either Sirolimus-eluting or any uncoated-stent, was the default strategy in patients with a reference vessel diameter greater than or equal to 2.5 mm at visual estimation. Crossover from a Sirolimus-eluting stent to other stent types was allowed only after failure of a Sirolimus-stent implantation attempt, or when there were no available stent sizes that matched the coronary reference diameter.

Aggrastat is not currently approved for use in STEMI patients or as adjunctive therapy in patients undergoing percutaneous coronary intervention. Aggrastat is indicated for the prevention of early myocardial infarction in patients presenting with unstable angina or non-Q-wave myocardial infarction with the last episode of chest pain occurring within 12 hours and with ECG changes and/or elevated cardiac enzymes. Patients most likely to benefit from Tirofiban treatment are those at high risk of developing myocardial infarction within the first 3-4 days after onset of acute angina symptoms including for instance those that are likely to undergo an early PTCA.

Source: ESC Meeting, 2010

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