HJB647 Phase 1b Study in Japanese Healthy Participants With Elevated Blood Pressure and Patients With Hypertension

Inclusion Criteria: * Japanese healthy participants with elevated blood pressure (Part 1) and patients with mild-to-moderate hypertension (Part 2) * Age: 18 to 55 years (Part 1) and 18 to 60 years (Part 2) * Body weight: * Male: ≥ 50.0 kg * Female: ≥ 45.0 kg * Body Mass Index (BMI): 18.0 to 30.0 kg/m² * Axillary body temperature: 35.0-37.5 °C * Heart rate: 50-90 bpm * Blood pressure criteria are as follows: * Part 1: Healthy Participants with Elevated Blood Pressure Screening: Systolic Blood Pressure (SBP): 120 ≤ SBP ≤ 139 mmHg; Diastolic Blood Pressure (DBP): 60 ≤ DBP ≤ 94 mmHg Baseline (Day -1): SBP: 120 ≤ SBP ≤ 179 mmHg; DBP: 60 ≤ DBP ≤ 109 mmHg * Part 2: Patients with Hypertension Screening and Baseline (Day -1): SBP: 140 ≤ SBP ≤ 179 mmHg; DBP: 60 ≤ DBP ≤ 109 mmHg Exclusion Criteria: * Significant illness, including infectious diseases that have not resolved within 30 days prior to baseline * History or current diagnosis of ECG or cardiac abnormalities indicating significant risk of safety for participants such as: * Concomitant clinically significant cardiac arrhythmias, e.g., sustained ventricular tachycardia, and clinically significant second- or third-degree AV block without a pacemaker. * History of familial long QT syndrome or known family history of Torsades de Pointes * Resting QT interval corrected by Fridericia's formula (QTcF) ≥ 450 msec (male) or ≥ 460 msec (female) at screening * At screening, hypokalemia or hypomagnesemia defined as potas…