Ticagrelor versus clopidogrel after fibrinolytic therapy in patients with ST-elevation myocardial infarction: Rationale and design of the ticagrelor in patients with ST elevation myocardial infarction treated with thrombolysis (TREAT) trial

BACKGROUND

The safety and efficacy of ticagrelor in patients with ST-elevation myocardial infarction (STEMI) treated with fibrinolytic therapy remain uncertain.

OBJECTIVES

The primary objective of the TicagRElor in pAtients with ST elevation myocardial infarction treated with Thrombolysis (TREAT) trial is to evaluate the short-term safety of ticagrelor when compared with clopidogrel in STEMI patients treated with fibrinolytic therapy. Key secondary objectives are to assess the safety and efficacy of ticagrelor compared with clopidogrel at 12-months.

DESIGN

The TREAT trial is a multicenter, randomized, phase III, Prospective randomized open blinded end-point (PROBE) study that enrolled 3,799 patients in 152 sites from 10 countries. Following administration of fibrinolytic therapy patients were randomized to a loading dose of ticagrelor 180 mg or clopidogrel 300 mg followed by a maintenance dose of ticagrelor 90 mg twice daily or clopidogrel 75 mg/day for 12-months. The primary outcome is the rate of TIMI major bleeding at 30-days and will be assessed for non-inferiority using an intention-to-treat analysis. Co-treatments include aspirin and anticoagulants. Other evidence based therapies are also recommended. Secondary efficacy outcome include a composite of death from vascular causes, myocardial infarction, stroke, severe recurrent ischemia, transient ischemic attack or other arterial thrombotic event. All-cause mortality as well as individual components of the combined efficacy endpoint will also be ascertained.

SUMMARY

TREAT is an international randomized controlled trial comparing ticagrelor with clopidogrel in STEMI patients treated with fibrinolytic therapy. The results of this trial will inform clinical practice and international guidelines.

Ticagrelor vs Clopidogrel After Fibrinolytic Therapy in Patients With ST-Elevation Myocardial Infarction: A Randomized Clinical Trial

Importance

The bleeding safety of ticagrelor in patients with ST-elevation myocardial infarction treated with fibrinolytic therapy remains uncertain.

Objective

To evaluate the short-term safety of ticagrelor when compared with clopidogrel in patients with ST-elevation myocardial infarction treated with fibrinolytic therapy.

Design, Setting and Participants

We conducted a multicenter, randomized, open-label with blinded end point adjudication trial that enrolled 3799 patients (younger than 75 years) with ST-segment elevation myocardial infarction receiving fibrinolytic therapy in 152 sites from 10 countries from November 2015 through November 2017. The prespecified upper boundary for noninferiority for bleeding was an absolute margin of 1.0%.

Interventions

Patients were randomized to ticagrelor (180-mg loading dose, 90 mg twice daily thereafter) or clopidogrel (300-mg to 600-mg loading dose, 75 mg daily thereafter). Patients were randomized with a median of 11.4 hours after fibrinolysis, and 90% were pretreated with clopidogrel.

Main Outcomes and Measures

The primary outcome was thrombolysis in myocardial infarction (TIMI) major bleeding through 30 days.

Results

The mean (SD) age was 58.0 (9.5) years, 2928 of 3799 patients (77.1%) were men, and 2177 of 3799 patients (57.3%) were white. At 30 days, TIMI major bleeding had occurred in 14 of 1913 patients (0.73%) receiving ticagrelor and in 13 of 1886 patients (0.69%) receiving clopidogrel (absolute difference, 0.04%; 95% CI, -0.49% to 0.58%; P < .001 for noninferiority). Major bleeding defined by the Platelet Inhibition and Patient Outcomes criteria and by the Bleeding Academic Research Consortium types 3 to 5 bleeding occurred in 23 patients (1.20%) in the ticagrelor group and in 26 patients (1.38%) in the clopidogrel group (absolute difference, -0.18%; 95% CI, -0.89% to 0.54; P = .001 for noninferiority). The rates of fatal (0.16% vs 0.11%; P = .67) and intracranial bleeding (0.42% vs 0.37%; P = .82) were similar between the ticagrelor and clopidogrel groups, respectively. Minor and minimal bleeding were more common with ticagrelor than with clopidogrel. The composite of death from vascular causes, myocardial infarction, or stroke occurred in 76 patients (4.0%) treated with ticagrelor and in 82 patients (4.3%) receiving clopidogrel (hazard ratio, 0.91; 95% CI, 0.67-1.25; P = .57).

Conclusions and Relevance

In patients younger than 75 years with ST-segment elevation myocardial infarction, delayed administration of ticagrelor after fibrinolytic therapy was noninferior to clopidogrel for TIMI major bleeding at 30 days.

Trial Registration

clinicaltrials.gov Identifier: NCT02298088.