A Clinical Trial Evaluating the Safety and Tolerability, Biodistribution and Radiation Dosimetry, and Pharmacokinetics of Flotufolastat F-18 Injection in Healthy Chinese Adults

1. Have the ability to understand the content of study and voluntarily sign the informed consent form.
2. Healthy male or female, aged 18-60 (included).
3. Body mass index (BMI) between 19 and 26 kg/m² (included).
4. Vital signs, physical examination, 12-lead electrocardiogram (ECG), chest X-ray (posterior-anterior view), and abdominal ultrasound are normal, or any abnormalities that are diagnosed clinically insignificant.
5. Clinical laboratory test results are within normal ranges or any abnormalities that are diagnosed clinically insignificant.
6. Have the ability to communicate effectively with the investigator and comply with the study requirement to follow-up.
7. Female subject shouldcontracept effectively during the study period and 6 months after the study completed (effective contraception includes sterilization, intrauterine hormonal devices, condoms, contraceptive pills/agents, abstinence, or partner vasectomy). Male subject should agree to use contraception during the study period and 6 months after the study completed.

Exclusion Criteria:

1. Claustrophobia or inability to tolerate imaging examinations for any other reason.
2. Have a history of epilepsy or seizures, excluding childhood febrile seizures.

3. With chronic diseases, including but not limited to:

   1. cardiovascular, respiratory, gastrointestinal, urinary, hematological disease, neurological, endocrine, metabolic, or musculoskeletal diseases, or a history thereof.
   2. history of psychiatric disorders or currently significant psychiatric conditions
4. Have a history of asthma or allergies.
5. Have a history of malignant tumors.
6. Present any condition that may interfere with the absorption or metabolism of the investigational drug, or that may affect study results, as determined by the investigator to be clinically significant.
7. Underwent any surgical procedure within 3 months before administration or planned surgery during the study period.
8. Accomplished the blood donation or significant blood loss (>400 mL) within 3 months before administration or during the screening period.
9. Insufficient venous access (two distinct venous lines are required for investigational drug administration and PK sampling).
10. Known allergy to the active ingredient or any excipients of the investigational product.
11. Took any medications, including prescription, over-the-counter drugs, or herbal remedies, within 14 days before administration.
12. Participated any other new drug's clinical trial within 4 weeks prior to the administration or within 5 half-lives of the investigating drug (whichever is longer).
13. Radiopharmaceutical imaging or treatment within 7 days prior to screening or within 5 half-lives of the radiopharmaceutical (whichever is longer).
14. Pregnant or breastfeeding women.
15. Abnormal serological results (hepatitis B surface antigen, syphilis treponemal antibody, human immunodeficiency virus antibody, hepatitis C antibody) diagnosed clinically significant by the investigator.
16. QTc intervalis longer than 450 milliseconds during the screening period.
17. Major occupational exposure to ionizing radiation in the past 10 years (e.g., more than 50 mSv/year) or exposure to radioactive materials or ionizing radiation for therapeutic or research purposes.
18. Any reason determined by the investigator that could not complet the study.