A randomized, double-blind, placebo-controlled, dose-escalation Phase I clinical study to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of single intravenous administration of ZKLJ02 injection in healthy Chinese research participants

Inclusion Criteria:

1. Able to provide informed consent and willing to comply with the study procedures;
2. Age between 18 and 45 years (inclusive), regardless of gender;
3. No clinically significant past or current medical history of cardiovascular, hepatic, renal, gastrointestinal, neurological, respiratory, psychiatric, or metabolic disorders, as determined by the investigator;
4. Physical examination, laboratory tests, 12-lead ECG, and vital signs are all normal or show abnormalities that are not clinically significant;
5. Body mass index (BMI) between 19.0 and 26.0 kg/m^2 (inclusive); body weight not less than 50 kg for males and not less than 45 kg for females;
6. Men with reproductive potential and women of childbearing potential must have no plans for pregnancy, sperm donation, or oocyte donation from the time of informed consent until 30 days after the final study visit, and must agree to use effective contraception.

Exclusion Criteria:

1. Individuals with a history of definite drug or food allergy, or known allergic reaction to any component of this product;
2. Known or suspected malignant tumors;
3. History of unexplained syncope, symptomatic hypotension, or hypoglycemia;
4. History or family history of long QT interval syndrome, or ECG showing QTcF >= 450 ms in males or >= 470 ms in females;
5. History of chronic diarrhea, malabsorption, unexplained weight loss, or food intolerance;
6. Individuals with a history of intracranial hemorrhage (e.g., after traffic accidents), stroke, or cerebrovascular disease;
7. Any disease (e.g., acute gastritis, gastrointestinal ulcers, gastrointestinal bleeding, Henoch-Schönlein purpura, systemic lupus erythematosus, etc.) or medical history (e.g., coagulation disorders, history of intracranial hemorrhage, history of intraocular hemorrhage, history of hemophilia, history of von Willebrand disease, etc.) that, in the investigator's judgment, could alter or increase the tendency to bleed;
8. Regular and continuous use within 3 months prior to screening of medications affecting coagulation function (e.g., clopidogrel, ticlopidine, dipyridamole, warfarin-like anticoagulants, novel oral anticoagulants such as rivaroxaban, apixaban, etc.), or prior treatment with anticoagulants such as heparin, low-molecular-weight heparin, or fibrinolytic agents;
9. Presence of significant factors affecting normal venipuncture, such as history of heparin allergy, history of heparin-induced thrombocytopenia, inability to tolerate venipuncture, or history of needle or blood phobia;
10. Positive test results for human immunodeficiency virus (HIV) antibody, hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) antibody, or syphilis antibody;
11. Blood donation or blood loss of more than 500 mL within 3 months prior to screening;
12. Participation in any other drug or medical device clinical trial within 3 months prior to screening, or currently participating in another clinical trial, or still within five half-lives of an investigational medicinal product at the time of screening;
13. Use of any prescription medication, over-the-counter drug, or dietary supplement within 14 days or five half-lives (whichever is longer) prior to the first administration of the study drug;
14. Hospitalization or major surgery within 6 months prior to screening;
15. History of drug abuse within 9 months prior to screening;
16. Individuals with a history of alcoholism or regular alcohol consumption within 9 months prior to screening, defined as more than 14 alcohol units per week (14 units = 8 bottles of beer (500 mL each, 3.5% alcohol content) or 500 g of baijiu (45% alcohol content) or 1.5 bottles of wine (750 mL each, 13% alcohol content)), or those unwilling to abstain from alcohol during the study period;
17. Study participants who smoked more than 5 cigarettes per day in the past 6 months, or used tobacco-containing alternative products in equivalent amounts, or who cannot ensure complete abstinence from smoking during the study period;
18. Pregnant or lactating women, those with a positive pregnancy test result, and female study participants who engaged in unprotected sexual activity within 2 weeks prior to the start of screening;
19. Onset of acute illness during the screening phase or prior to the first administration of study medication;
20. Consumption within 48 hours before dosing of any food or beverage containing caffeine, alcohol, xanthine, or grapefruit components (e.g., coffee, strong tea, chocolate, etc.);
21. Positive breath alcohol test result or positive drug abuse screening result;
22. Any individual with special dietary requirements who cannot comply with the standardized diet (e.g., intolerance to standard meals, lactose intolerance, etc.);
23. Other conditions deemed by the investigator as unsuitable for participation in this study.