Bioequivalence Study of Tenofovir Disoproxil Fumarate Tablets in Healthy Chinese Subjects

Inclusion Criteria:

1. Healthy male and female subjects aged 18 years or older (including boundary values);
2. Male weight ≥ 50 kg, female weight ≥ 45 kg, and body mass index (BMI) within the range of 19-26 kg/m² (including boundary values), where BMI = weight (kg) / height² (m²);
3. Determined to be healthy based on medical history, physical examination, vital signs, and laboratory tests including blood routine, urinalysis, liver and kidney function, blood glucose, and electrocardiogram (ECG) during the screening period. All test results must be within the normal range consistent with age and sex, or meet the protocol requirements, or if outside the normal range, be judged by the investigator as having "no clinical significance (NCS)";
4. No recent plans for pregnancy and agreement to use effective non-pharmacological contraceptive measures during the study period and within one month after study completion; Subjects able to communicate well with the investigator, understand and comply with all requirements of this study, and provide written informed consent.

Exclusion Criteria:

1. A history of significant drug or food allergies judged by the investigator to be clinically meaningful, or known allergy to the study drug/class of drugs;
2. Regular use of sedatives, hypnotics, or other addictive drugs, or a positive urine drug screen prior to dosing;
3. A history of drug abuse, heavy smoking, or alcohol abuse within 12 months prior to dosing;
4. Use of any prescription drugs or Chinese herbal supplements within 4 weeks prior to the first dose of the study drug, and/or use of any over-the-counter (OTC) medications or dietary supplements (including vitamins) within 2 weeks prior to the first dose of the study drug;
5. Blood donation or participation in another clinical trial within 3 months prior to enrollment;
6. A recent history (within the past 3 years) of autonomic nerve dysfunction and/or current medical history (e.g., recurrent syncope, palpitations, etc.);
7. A past medical history of cardiovascular, hepatic, renal, pulmonary, gastrointestinal, or neurological diseases, any condition or illness that may significantly affect drug absorption, distribution, metabolism, or excretion, or any condition or illness that may pose a hazard to the subject participating in the trial. The investigator should consider the following medical history or conditions: history of inflammatory gastrointestinal disease, gastroesophageal reflux, gastrointestinal or rectal bleeding; history of pancreatic injury or pancreatitis; major surgical history such as gastrectomy, gastrointestinal anastomosis, or enterectomy. Clinically significant abnormalities in liver function laboratory tests, such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), or bilirubin, indicating liver disease or liver injury, or exceeding 1.5 times the upper limit of normal;
8. A history or evidence of acute or chronic renal insufficiency, such as serum creatinine above the upper limit of normal (still above the upper limit after repeated testing), clinically significant proteinuria, history of kidney transplantation, etc. A history of severe vomiting or diarrhea within one week prior to the trial;
9. Subjects with an estimated endogenous creatinine clearance rate (calculated from serum creatinine levels during the screening period) below 80 mL/min (formula for endogenous creatinine clearance rate: Ccr = (140 - age) × body weight (kg) / [72 × Scr (mg/dL)] or Ccr = [(140 - age) × body weight (kg)] / [0.818 × Scr (μmol/L)]. Note the units of serum creatinine in the calculation; for female subjects, multiply the result by 0.85);
10. Pregnant or lactating women, or women of childbearing age who cannot comply with the required contraceptive measures;
11. Positive test for hepatitis B surface antigen (HBsAg), hepatitis C antibody (anti-HCV), syphilis, or HIV antibody;
12. Subjects on a special diet, e.g., vegetarians;
13. Subjects who refuse to abstain from any beverages or foods containing methylxanthines, such as caffeine (coffee, tea, cola, chocolate, etc.), from 48 hours before the start of the trial until the end of the trial;
14. Subjects who refuse to abstain from any beverages or foods containing grapefruit from 7 days before the start of the trial until the end of the trial;
15. Any other condition deemed by the investigator as unsuitable for enrollment.