This study is a multi-center, randomized, double-blind, double-dummy, placebo-controlled, single dose escalation study aimed at evaluating the overall safety, tolerability, and preliminary efficacy of HRS-7450 in patients with acute ischemic stroke.

Inclusion Criteria:

1. Fully understand and voluntarily participate in this study, and sign an informed consent form (the informed consent form can be voluntarily signed by the individual or legal representative);
2. 18 ≤ Age ≤ 80 years old;
3. The onset time is within 4.5 to 24 hours, and medication can be completed within 24 hours of onset (onset time is defined as the patient's last normal time);
4. Clinically diagnosed as acute ischemic stroke (diagnosis follows the Chinese Guidelines for the Diagnosis and Treatment of Acute Ischemic Stroke 2023);
5. mRS score ≤ 2 before the first episode;
6. When screening, the National Institutes of Health Stroke Scale (NIHSS) scores from 3 to 25 (including both ends);
7. Female and male participants with fertility must agree to use efficient contraception measures from the signing of the informed consent form until one month after the last administration of the investigational drug, without a birth plan, and without donating sperm/eggs. (See "Contraceptive methods" in the attachment for details).

Exclusion Criteria:

1. Treatment with ateplase, teneplase, or other thrombolytic drugs;
2. Proposed endovascular treatment;
3. Intracranial hemorrhagic diseases;
4. Aortic arch dissection;
5. NIHSS awareness score 1a>2 points;
6. Epileptic seizures or neurological dysfunction after seizures, or combined with other neurological/psychiatric disorders leading to uncooperative or non cooperative physical examinations;
7. Non enhanced CT shows a low-density shadow greater than one-third of the blood supply area of the middle cerebral artery or an ASPECT score of less than 6 points in the anterior circulation;
8. Previous history of intracranial hemorrhage;
9. Intracranial tumors, arteriovenous malformations, and giant aneurysms;
10. Acute occlusion of the internal carotid artery due to carotid artery dissection;
11. Multiple infarcts in areas supplied by multiple large blood vessels;
12. Have a history of ischemic stroke, severe traumatic brain injury, or intracranial or spinal surgery in the past month;
13. Gastrointestinal or urinary system bleeding within the past 2 weeks;
14. Major surgical procedures or severe injuries within the past 2 weeks;
15. Arterial puncture that is difficult to compress and stop bleeding within the past week;
16. Active visceral bleeding;
17. After actively reducing blood pressure, systolic blood pressure ≥ 180mmHg and/or diastolic blood pressure ≥ 100mmHg;
18. Screening period examination: Blood glucose<2.8 or>22.2mmol/L, platelet<100 * 109/L, other findings suggestive of a high risk of bleeding;
19. Within the past 3 months, acute ST segment elevation myocardial infarction (MI) and/or acute decompensated heart failure occurred, and/or QTc>520 milliseconds, and/or due to acute coronary syndrome MI、 Hospitalization or involuntary coronary intervention for cardiac arrest; Or New York Heart Association Grade III/IV heart failure; Or known to have ventricular tachycardia;
20. History of severe liver disease, or aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) and/or glutamyltransferase (GGT) ≥ 3 x ULN and/or total bilirubin (TBIL) ≥ 2 x ULN.
21. Severe kidney disease with clinical significance, or eGFR<45mL/min/1.73 m2;
22. Subjects with known potential bleeding constitution or coagulation dysfunction;
23. Subjects with a known history of glucose-6-phosphate dehydrogenase deficiency or a family history;
24. Known to be allergic to any component of HRS-7450 or its formulations or placebo;
25. Received therapeutic or prophylactic doses of heparin treatment within 24 hours;
26. Oral coumarin anticoagulants with an international standardized ratio INR>2.7;
27. Use thrombin inhibitors, Xa factor inhibitors, or other anticoagulant drugs under study within48 hours;
28. Use platelet IIb/IIIa receptor inhibitors within 48 hours;
29. Pregnant women, or women of childbearing age who test positive for pregnancy, or those who are breastfeeding;
30. Participate in clinical studies of other drugs or devices within the first three months of the screening period (sign an informed consent form and receive treatment with the trial drug/device);
31. The terminal state of the disease, with an expected survival period of no more than 1 year;
32. Other situations where the researcher deems it inappropriate to participate in this experiment.