Ischemic stroke is a common disease of nervous system, with high morbidity, mortality and disability, which seriously threatens human health. According to the latest global burden of disease research, the overall lifetime risk of stroke in China is 39.9%, ranking first in the world, which means that about two out of every five people will suffer a stroke in their lifetime. In addition, stroke is also the first cause of life lost due to disease in China. Intravenous thrombolysis is one of the most effective treatment methods for AIS at present, and the commonly used thrombolytic drug is recombinant tissue plasminogen activator (rt-PA). Although the recanalization rate of intravenous thrombolysis with alteplase can reach about 50%, in actual treatment, about 1/3 of patients experience reocclusion after thrombolytic therapy, resulting in neurological deterioration.~Tirofiban is a highly effective and reversible non-peptide platelet surface glycoprotein (GP) IIb/IIIa receptor antagonist, which can competitively inhibit the binding of fibrinogen and platelet GP IIb/IIIa receptor, inhibit platelet aggregation, prolong bleeding time, and inhibit thrombosis. Tirofiban can inhibit platelet aggregation within 5 min after intravenous injection, with the time to peak of < 30 min, and achieve stable plasma concentration within 1 hour. Due to the short half-life (1.4-1.8 h), continuous administration is required, and platelet aggregation is restored in approximately 50% of patients 4 h after discontinuation. Therefore, tirofiban has the characteristics of rapid antiplatelet aggregation and rapid recovery of platelet function after discontinuation, and does not significantly increase the risk of bleeding events while preventing thrombosis.~For AIS patients whose onset time is within the thrombolytic time window, the results of preliminary research showed that tirofiban hydrochloride injection combined with intravenous thrombolytic therapy can reduce the volume of intracranial lesions in patients, better improve the symptoms of neurological deficits in patients than intravenous thrombolytic therapy alone, and the long-term neurological outcomes of patients with combined therapy are better than those with intravenous thrombolytic therapy alone. Observation of the efficacy of tirofiban at different time points after intravenous thrombolysis with alteplase in AIS showed that tirofiban 2-12 hours after intravenous thrombolysis had the greatest benefit in improving neural function.~With the accumulation of clinical experience in the treatment of ischemic cerebrovascular diseases and the development and popularization of interventional therapy, some shortcomings of oral antiplatelet drugs in the treatment of reocclusion have been found, such as insufficient antithrombotic strength, slow onset time, differences in patients' individuality, poor patient compliance and other problems. In addition, due to safety considerations, current guidelines at home and abroad do not recommend the administration of antiplatelet therapy within 24 hours after intravenous thrombolysis, which limits the therapeutic effect of AIS to some extent. Based on the pathophysiological mechanism of reocclusion and referring to the application experience of tirofiban in the cardiovascular field, many experts at home and abroad have carried out a series of clinical researches on the early application of tirofiban after intravenous thrombolytic and/or endovascular therapy to improve the recanalization rate and reduce reocclusion, showing good safety and efficacy, which has been affirmed by a number of diagnosis and treatment guidelines. However, although a large number of clinical experience and various clinical researches have proved the safety and efficacy of tirofiban's antiplatelet effect in different AIS treatments, there has been no large-sample randomized controlled clinical trial to verify its clinical efficacy in AIS.~This is a Phase 2 clinical study, and the subjects are patients with acute ischemic stroke who have received intravenous thrombolysis with alteplase within 4.5 hours of onset. The study is to evaluate the safety and efficacy of different doses of tirofiban hydrochloride sodium chloride injection compared with placebo in patients with acute ischemic stroke after intravenous thrombolytic therapy with alteplase.~Subjects who meet the inclusion criteria but do not meet the exclusion criteria are randomly divided into three groups: two groups with different doses of tirofiban hydrochloride sodium chloride injection and one placebo-controlled group, respectively, namely: Group 1 (tirofiban hydrochloride sodium chloride injection group at 0.25 μg/kg/min (0.005 ml/kg/min)); Group 2 (tirofiban hydrochloride sodium chloride injection group at 0.4 μg/kg/min (0.008 ml/kg/min)); and Group 3 (placebo 0.9% sodium chloride injection).~It should be ensured that subjects are given tirofiban or placebo within 12 hours after the end of thrombolysis. The patients are observed immediately after the end of administration, 4 hours after the end of administration, 48 hours, 7 days, and 14 days after the start of administration, and followed up to 90 days after the start of administration. The study endpoints include: the incidence of symptomatic intracranial hemorrhage within 48 hours after the start of administration (primary safety index), the incidence of intracranial hemorrhage within 48 hours after the start of administration (secondary safety index), etc., the proportion of subjects with mRS 0-1 score on the modified Rankin scale 90 days after the start of administration (primary efficacy index), and the value of change in NIHSS score from baseline at 48 hours, 7 and 14 days after the start of administration (secondary efficacy index), etc. The safety and efficacy of different doses of tirofiban hydrochloride sodium chloride injection compared with placebo in patients with acute ischemic stroke after intravenous thrombolytic therapy with alteplase are evaluated by statistical analysis of endpoint indexes.
The study is a prospective, multicenter, randomized, double-blind, placebo-controlled study evaluating the safety and efficacy of tirofiban in combination with intravenous thrombolytic therapy with alteplase in acute ischemic stroke