Abstract TP143: Endovascular Treatment With Versus Without Tirofiban For Stroke Patients With Large Vessel Occlusion: The Multicenter, Randomized, Placebo-controlled, Double-blind RESCUE BT Clinical Trial

Abstract

Background: As a glycoprotein IIb/IIIa receptor inhibitor, tirofiban may help reduce the risk of vascular complications during percutaneous transluminal coronary intervention. However, evidence on whether tirofiban improve the outcomes of stroke patients with large vessel occlusion who are receiving endovascular treatment is limited. Objective: This trial aims to assess whether additional intravenous tirofiban therapy can improve the clinical outcomes of stroke patients with large vessel occlusion who undergo endovascular treatment within 24 hours of symptom onset. Methods and Design: The Endovascular Treatment With versus Without Tirofiban for Stroke Patients With Large Vessel Occlusion (RESCUE BT) Trial is an investigator-initiated, randomized, placebo-controlled, double-blind, multicenter trial. Up to 930 eligible patients will be consecutively randomized to tirofiban or control group in 1:1 ratio over three years from approximate 50 endovascular-capable stroke centers in China. Outcomes: The primary end-point is the disability level measured by overall distribution of the 90-day modified Rankin Scale score. The primary safety end-points are symptomatic intracerebral hemorrhage at 48 hours and mortality at 90 days. Trial status: The trial screening and enrollment began on 10 October, 2018, and now the randomization is still ongoing. We expect that the enrollment will be end in October 2021, and the trial results will be revealed in February 2022. Trial registry number: ChiCTR-INR-17014167 ( www.chictr.org.cn ).

Antiplatelet Therapy in Neurointervention

“…Despite the initial promise of tirofiban as adjunctive treatment for mechanical thrombectomy, this was not demonstrated in the first RCT RESCUE BT. 1 MR CLEAN MED 2 failed to demonstrate a benefit of aspirin or heparin and indicated an increased risk of sICH in routine use for mechanical thrombectomy. When acute stent occlusion or platelet aggregation occurs, IV GPIIb/IIIa inhibitors can be utilized as rescue therapy.…”

“…However, the RESCUE BT randomized trial in China found that in patients with large-vessel occlusion, IV tirofiban administered prior to thrombectomy did not result in improved 90-day outcomes in the overall cohort. 1 Subgroup analysis demonstrated a favorable point estimate for tirofiban among the intracranial atherosclerotic disease (ICAD) subgroup; however, the test for interaction was not significant. 1 The "Safety and efficacy of aspirin, unfractionated heparin, both, or neither during endovascular stroke treatment" trial (MR CLEAN-MED) patients were randomly assigned (1:1) to receive either periprocedural IV aspirin (300 mg bolus) or no aspirin, and randomly assigned (1:1:1) to receive moderate-dose unfractionated heparin (5,000 IU bolus followed by 1,250 IU/h for 6 hours), low-dose unfractionated heparin (5,000 IU bolus followed by 500 IU/h for 6 hours), or no unfractionated heparin.…”

“…1 Subgroup analysis demonstrated a favorable point estimate for tirofiban among the intracranial atherosclerotic disease (ICAD) subgroup; however, the test for interaction was not significant. 1 The "Safety and efficacy of aspirin, unfractionated heparin, both, or neither during endovascular stroke treatment" trial (MR CLEAN-MED) patients were randomly assigned (1:1) to receive either periprocedural IV aspirin (300 mg bolus) or no aspirin, and randomly assigned (1:1:1) to receive moderate-dose unfractionated heparin (5,000 IU bolus followed by 1,250 IU/h for 6 hours), low-dose unfractionated heparin (5,000 IU bolus followed by 500 IU/h for 6 hours), or no unfractionated heparin. In total, 663 patients were randomized, of whom 628 (95%) were included in the modified intention-to-treat population.…”

“…The use of antiplatelet medication has also been explored as an adjunct prior to and during mechanical thrombectomy. 1,2 During endovascular coiling of aneurysms, antiplatelet therapy may be used when there is a concern of thrombotic events due to coil positioning or coil protrusion to the parent vessel. This may be acutely required when there is a visible filling defect in the lumen of the parent vessel on angiography or acute stent occlusion raising concern for acute platelet aggregation or thrombus formation.…”

“…There are also antiplatelet medications that can be used for rescue treatment in the context of acute stent occlusion and platelet aggregation. More recently, intravenous (IV) antiplatelet medications have been studied for use with mechanical thrombectomy for acute stroke 1,2 Antiplatelet medications differ in their mechanisms of action, pharmacodynamics, pharmacokinetics, and indications. Their adverse effects are broad, with the risk of intracranial hemorrhage being of primary concern, particularly in the acute presentation of stroke or aneurysmal rupture.…”