A Multicenter, Randomized, Double-Blind Phase 3 Trial of KDF1901 in Patients With Essential Hypertension

Inclusion Criteria: 1. Male or female participants aged ≥19 years at the time of screening. 2. Participants who meet one of the following blood pressure criteria at screening: 1. If not currently receiving antihypertensive medication for at least 4 weeks (treatment-naïve): * Mean Sitting Systolic Blood Pressure (MSSBP) ≥160 mmHg and \<200 mmHg 2. If currently receiving antihypertensive medication: * MSSBP ≥140 mmHg and \<200 mmHg * For participants with cardiovascular disease, diabetes mellitus, or microalbuminuria (e.g., persistent proteinuria or hematuria), the range is: MSSBP ≥130 mmHg and \<200 mmHg 3. Willing and able to provide written informed consent prior to participation in the study. 4. At baseline (Visit 3), participants must have MSSBP ≥140 mmHg and \<200 mmHg. * For participants with cardiovascular disease, diabetes mellitus, or microalbuminuria: MSSBP ≥130 mmHg and \<200 mmHg 5. At least 70% compliance with run-in period medication, as assessed by tablet count. Exclusion Criteria: 1. Mean sitting diastolic blood pressure (MSDBP) ≥110 mmHg at screening (Visit 1) or baseline (Visit 3) 2. Difference in blood pressure between arms: MSSBP ≥20 mmHg and MSDBP ≥10 mmHg at screening 3. History or presence of secondary hypertension or suspected secondary hypertension, including: * Aortic coarctation, pheochromocytoma, Cushing's syndrome, hyperaldosteronism, polycystic kidney disease 4. Severe pulmonary, cardiac, or vascular conditions, such as: * Pulmonary hypertension, severe heart failure (NYHA class III or IV), hypertrophic cardiomyopathy, aortic aneurysm, thrombocytopathy 5. History of serious cardiovascular events or interventions within 24 weeks prior to screening: * Myocardial infarction, unstable angina, coronary revascularization (PCI/CABG) 6. History of cerebrovascular disorders within 24 weeks prior to screening: * Stroke, TIA, cerebral hemorrhage 7. History of ocular conditions within 24 weeks prior to screening: * Retinal hemorrhage, optic neuropathy, severe visual impairment 8. History of malignancy within 5 years prior to screening, except: * Successfully treated and in remission for ≥2 years, or * Basal cell carcinoma or squamous cell carcinoma of the skin 9. Hereditary blood disorders or history of angioedema related to ACE inhibitors or ARBs 10. History of galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption 11. Diagnosis of inflammatory bowel disease (e.g., Crohn's disease, ulcerative colitis) within 48 weeks prior to screening 12. Clinically significant conditions affecting drug absorption, distribution, metabolism, or excretion 13. Symptoms of orthostatic hypotension or risk of falls or syncope 14. Severe anemia, leukopenia, or thrombocytopenia at screening 15. Heart failure NYHA class III or IV 16. Known serious arrhythmias, including ventricular tachycardia or fibrillation 17. Known autoimmune disease or connective tissue disorder 18. Clinically significant renal, hepatic, or cardiovascular disease 19. eGFR \<30 mL/min/1.73 m² or serum creatinine ≥2.0 mg/dL 20. ALT or AST \>3× upper limit of normal (ULN) 21. Serum K+ \<3.5 or \>5.5 mmol/L, Na+ \<135 mmol/L, Ca2+ \>10.5 or \<2.63 mmol/L 22. Requiring long-term immunosuppressive therapy or systemic corticosteroids 23. Clinically significant chronic inflammatory conditions 24. History of major surgery or active GI disorders 25. Type 2 diabetes mellitus with HbA1c ≥9.0% 26. Known edematous disorders (e.g., untreated nephrotic syndrome) 27. Requirement for prohibited medications (emergency drugs) during study period (Visit 1-6) 28. Use of lithium therapy 29. Use of terfenadine or astemizole 30. Hypersensitivity to study drugs, dihydropyridine-class CCBs, thiazide diuretics, or sulfonamides 31. History or suspicion of drug or alcohol abuse 32. Pregnancy or lactation 33. Women of childbearing potential or male participants not agreeing to use reliable contraception during study 34. Participation in other clinical trials or use of investigational products within 4 weeks prior to screening 35. Judged by the investigator to be otherwise unsuitable for study participation