Tirofiban plus endovascular thrombectomy is a safe, effective treatment for patients with large vessel occlusion (LVO) due to intracranial atherosclerosis (ICAD), according to study findings published in Neurology.
ICAD is often associated with the development of a LVO, particularly among Black, Hispanic, and Asian populations. Patients who experience a LVO linked to ICAD exhibit high rates of recanalization failure following endovascular thrombectomy, often leading to the need for additional angioplasty and/or a permanent stent.
It is believed tirofiban, a selective glycoprotein IIb/IIIa receptor inhibitor, may have the ability to inhibit the bridging of fibrinogen with platelets and thus, prevent the development of arterial thrombosis in these individuals. In fact, during an endovascular thrombectomy procedure in patients who experience an ischemic stroke, tirofiban has been commonly used as an adjuvant medication.
For the study, researchers sought to explore the efficacy and safety of intravenous (IV) tirofiban prior to undergoing endovascular thrombectomy in patients with a LVO associated with ICAD. They also sought to identify any possible mediators for the clinical efficacy of tirofiban.
The prospective, randomized, double-blind, placebo-controlled Endovascular Treatment With vs Without Tirofiban for Patients with Large Vessel Occlusion Stroke (RESCUE BT) trial was conducted to evaluate IV tirofiban plus endovascular therapy vs placebo plus endovascular therapy in individuals who present with an occlusion of the internal carotid artery or middle cerebral artery within 24 hours of onset of symptoms. RESCUE-BT was performed at 55 centers in China between October 2018 and October 2021.
A total of 435 patients with acute stroke due to ICAD were included in the post-hoc analysis — 197 individuals in the tirofiban group and 238 individuals in the placebo group. The median participant age was 65 years (range, 56-72 years). Overall, 311 of the patients were men. The median National Institutes of Health Stroke Scale (NIHSS) score was 14 (range, 10-19).
Predictors of functional independence at 90 days included age, baseline NIHSS score, baseline Alberta Stroke Program Early CT [computed tomography] Score (ASPECTS), pretreatment systolic blood pressure, history of diabetes, and location of the occlusion.
A statistically significantly higher rate of functional independence at 90 days was reported in the tirofiban arm vs the placebo arm (49.7% vs 39.1%, respectively; adjusted odds ratio [aOR], 1.68; 95% CI, 1.11-2.56; P =.02). The adjusted common OR (acOR) with tirofiban vs placebo was 1.42 (95% CI, 1.10-1.99; P =.043).
Individuals in the tirofiban arm vs the placebo arm exhibited numerically lower mortality rates (1.42% vs 18.5%, respectively) and numerically higher rates of any intracranial hemorrhage (29.1% vs 23.2%, respectively), although these differences did not achieve statistical significance.
In the per-protocol population, sensitivity analysis showed that tirofiban compared with placebo was associated with a significantly higher rate of 90-day functional independence (57.6% vs 38.8%, respectively; aOR, 2.17; 95% CI, 1.31-3.60; P =.003), as well as less severity of disability (acOR, 1.82; 95% CI, 1.20-2.76; P =.005).
Additionally, the rate of first pass effect in the tirofiban arm vs the placebo arm was numerically higher (18.8% vs 13.9%, respectively; P =.17). Further, the number of thrombectomy passes was significantly lower in the tirofiban group than in the placebo group (P =.004). Thus, thrombectomy passes were examined as being a potential mediator of tirofiban effect on functional independence. Based on mediation analysis, tirofiban-reduced thrombectomy passes justified 20.0% (95% CI, 4.1%-76.0%) of the effect of tirofiban on functional independence.
“This study provides Class II evidence that tirofiban plus endovascular therapy improved 90-day outcome for patients with large vessel occlusion due to intracranial atherosclerosis,” the researchers stated.
A key limitation of the present study is that it was an exploratory analysis in an ICAD subgroup from the RESCUE BT trial and thus may have been underpowered. Further, the tirofiban dose used in this study was administered in the same fashion as in studies of patients with myocardial infarction, thus possibly resulting in a numerically higher risk for any intracranial hemorrhage.
Overall, the researchers acknowledged that tirofiban is an effective and well-tolerated adjuvant medication for endovascular thrombectomy in patients with LVO due to ICAD. However, they caution that future trials are warranted to confirm these findings.
Sang H, Xie D, Tian Y, et al. Association of tirofiban with functional outcomes after thrombectomy in acute ischemic stroke due to intracranial atherosclerotic disease. Neurology. Published online March 20, 2023. doi: 10.1212/WNL.0000000000207194