Study of SGB-3908 in Healthy Subjects and Mildly Hypertensive Subjects

Inclusion Criteria: * Has body mass index (BMI) ≥18 and ≤30 kg/m\^2 and has bodyweight ≥ 50 kg; * Has Systolic blood pressure (SBP) ≥100 mmHg and ≤150 mmHg and diastolic blood pressure (DBP) ≥65 mmHg and ≤95 mmHg at screening; Exclusion Criteria: * Has mental illness, liver and kidney disease, gastrointestinal disease, nervous system disease, or other related systemic diseases that affect the trial; * Has a history of hospitalization or other clinically significant diseases within 1 month before screening, major surgery within 6 months before screening, or other unstable conditions judged by the investigator; * Has a history of orthostatic hypotension or syncope; * Patients with clinically significant abnormalities confirmed by physical examination, 12-lead electrocardiogram, laboratory tests, etc., or those who meet any of the following conditions during screening need to be excluded: 1. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin higher than 1.5× upper limit of normal (ULN) 2. Serum creatinine (Cr) higher than ULN 3. Serum potassium higher than 5 mmol/L 4. QT/QTc interval prolongation during screening (QTcF\>450 ms)