Inclusion Criteria:
1. Signed informed consent form prior to any study-related procedures, with full understanding of the study content, procedures, and potential adverse reactions, and ability to complete the study as per protocol requirements.
2. Healthy male or female, aged ≥ 18 and ≤ 55 years on the day of signing the informed consent form.
3. Body weight: males ≥ 50 kg, females ≥ 45 kg; body mass index (BMI) between 19 and 26 kg/m² inclusive (BMI = weight (kg) / height² (m²)).
4. Vital signs, physical examination, laboratory tests (hematology, blood biochemistry, urinalysis, coagulation function, and thyroid function), and 12-lead electrocardiogram (ECG) findings are normal or clinically insignificant at screening and baseline.
5. Abdominal ultrasound, thyroid ultrasound, and chest X-ray findings are normal or clinically insignificant at screening.
6. Willing and able to undergo pain testing procedures and trained qualified.
7. Female participants of childbearing potential and male participants with partners of childbearing potential must have adopted contraceptive measures within 2 weeks prior to signing the informed consent form, and must agree to remain abstinent or use highly effective contraceptive methods from the signing of the informed consent form through the end of the follow-up period.
8. Female participants of childbearing potential must agree to use highly effective contraceptive methods during the study and for 3 months after the last dose; serum pregnancy test must be negative at screening and baseline, and must not be breastfeeding. Male participants must agree to use highly effective contraceptive methods and refrain from sperm donation during the study and for 3 months after the last dose.
Exclusion Criteria:
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1\. Presence of any of the following diseases or treatment history:
1. Current or previous history of any clinically significant disease involving the urinary, cardiovascular, endocrine, neurological, digestive, respiratory, hematopoietic, immune, psychiatric, or metabolic systems, or any other condition that, in the investigator's judgment, may interfere with the study results, such as intestinal diseases (including irritable bowel syndrome) and urinary tract infections.
2. History of malignancy (except for cancers that have been cured or in remission for ≥ 5 years, radically resected basal cell or squamous cell skin carcinoma, in situ cervical carcinoma, and resected colon polyps).
3. Any condition or disease that, in the investigator's judgment, may affect the absorption, metabolism, and/or excretion of the study drug.
4. Severe infection, severe trauma, or major surgery within 3 months prior to screening or baseline, or planned surgery during the study period.
5. Use of any medication (including prescription drugs, over-the-counter drugs, herbal medicines, dietary supplements, vitamin A and its derivatives, etc., except for routine vitamins and occasional use of acetaminophen) within 2 weeks prior to screening or baseline, or still within 5 half-lives of the drug at screening or baseline (whichever is longer); or planned use of non-study medications during the study period.
6. Participation in any other drug or medical device clinical trial within 3 months prior to screening or baseline, or planned participation during the study period, or still within 5 half-lives of the investigational drug at screening or baseline (whichever is longer).
2\. Any of the following laboratory findings at screening:
1. Sitting systolic blood pressure \< 90 mmHg or sitting diastolic blood pressure \< 50 mmHg at screening or baseline.
2. Orthostatic hypotension confirmed by repeat measurement within 15 minutes at screening or baseline.
3. Clinically significant 12-lead ECG abnormalities at screening or baseline; QTcF \> 450 ms for males or QTcF \> 460 ms for females.
4. Positive for hepatitis B surface antigen (HBsAg), human immunodeficiency virus (HIV) antibody, syphilis antibody, or hepatitis C virus (HCV) antibody at screening.
3\. General conditions:
1. Blood donation or significant blood loss (≥ 400 mL) within 8 weeks prior to screening or baseline, or blood transfusion within 4 weeks prior to screening or baseline; or intention to donate blood during the study period.
2. Vaccination within 2 weeks prior to screening or baseline, or planned vaccination during the study period.
3. Smoking history (average \> 5 cigarettes per day) within 4 weeks prior to screening or baseline, or inability to refrain from using any tobacco products during the study period.
4. Average daily alcohol intake \> 15 g within 4 weeks prior to screening or baseline (15 g alcohol is equivalent to approximately 450 mL beer, 150 mL wine, or 50 mL liquor), or inability to abstain from alcohol during the study period; or positive breath alcohol test at baseline.
5. History of drug abuse or dependence prior to screening or baseline; or positive urine drug screen at baseline.
6. Excessive consumption of tea, coffee, or caffeinated beverages (average \> 8 cups per day, 250 mL per cup) within 6 months prior to screening or baseline.
7. Consumption of special foods (such as grapefruit, grapefruit juice, or foods/beverages containing grapefruit juice, chocolate, tobacco, alcohol, caffeinated foods or beverages, etc.) within 48 hours prior to baseline.
8. Special dietary requirements or inability to comply with the standardized diet provided by the study center.
9. Dysphagia, difficulty in venous blood collection, or physical condition unable to tolerate intensive blood sampling.
10. Known allergy to any component of the investigational medicinal product; history of allergic diseases or allergic constitution.
11. Use of strong or moderate inhibitors/inducers of CYP2C9, or any inhibitors of P-gp, OATP1B1, OATP1B3, or OAT3 within 30 days prior to screening or planned during the study period.
12. Any other condition that, in the investigator's judgment, makes the participant unsuitable for participation in this study, including but not limited to any physiological or psychological condition that may increase the risk of the study, affect the participant's compliance with the protocol, or affect the participant's ability to complete the study.
