The purpose of this study is to evaluate the efficacy and safety of Candesartan/Amlodipine combined or alone and select better dose of CKD-330 in essential hypertension patients.

Inclusion Criteria:

• Age of 18 or above
• Essential hypertension with 90mmHg ≤ mean sitDBP ≤ 115mmHg on target arm at Visit 3
• Ability to provide written informed consent

Exclusion Criteria:

• nean sitDBP ≥ 116mmHg or mean sitSBP ≥ 200mmHg at Visit 1, Visit 2, Visit 3
• The change of mean sitDBP ≥ 10mmHg or mean sitSBP ≥ 20mmHg on target arm at Visit 1
• Known or suspected Stage 2 Hypertension (aortic coarctation, Primary hyperaldosteronism, renal artery stenosis, pheochromocytoma)
• Patients with congestive heart failure(NYHA class III~IV), ischemic heart disease, cardiomyopathy, heart valve disorder, arrhythmia, coronary artery bypass graft
• History of cerebrovascular disease as cerebral infarction, cerebral hemorrhage within 6 months
• Type I Diabets Mellitus, Type II Diabetes Mellitus with HbA1c > 8%
• History of severe or malignant retinopathy
• AST/ALT > UNL * 2, Serum Creatinine > UNL * 1.5, K > 5.5mEq/L
• Patients with acute or chronic inflammatory status, autoimmune disease
• Patients who need to take antihypertensive drug besides Investigational products
• Patients must be treated with medications prohibited for concomitant use during study period
• Hypersensitive to Candesartan/Amlodipine or other dihydropyridine drugs
• Hereditary angioedema or history of angioedema related to ACE inhibitor or angiotensin II receptor blockers
• History of malignant tumor within 5 years
• Patients who are dependent on drugs or alcohol
• History of disability to drug absorption, active inflammatory bowel syndrome with 12months, impaired pancreatic function, GI bleeding, obstructions of urinary tract
• Patients treated with other investigational product within 4 weeks at the time concents are obtained
• Women with pregnant, breast-feeding
• Not eligible to participate for study at the discretion of investigator