A majority of Korean doctors tend to add other antihypertensive rather than to titrate the same drug.

However, we try to induce doctors to titrate the Sevikar than to add other antihypertensive if patients are not controlled with Sevikar 5/20mg(amlodipine 5mg + omlesartan 20mg). As above, for patients who are not controlled with Sevikar 5/20mg, doctors will proceed to other prescription pattern with other choices of titration to Sevikar 5/40, 10/40mg.

It is important to evaluate BP lowering efficacy of Sevikar through the titration step in patients uncontrolled with Sevikar low dose. Thus, this study is designed to demonstrate the efficacy of Sevikar by titration in patients who are not controlled their BP with low dose of Sevikar.

Inclusion Criteria:

1. Male and female subjects > 55 years

2. Subject who has consent to participate by signing on the informed consent form

3. Uncontrolled hypertensive patients defined as:

   • Uncontrolled hypertensive: subjects who are mean SBP ≥ 140 mmHg after being treated with ARB(Valsartan 80mg or Candesartan 8mg) monotherapy during at least 4 weeks.

Exclusion Criteria:

1. Secondary hypertension
2. SeSBP ≥ 180mmHg
3. SeSBP difference ≥ 20mmHg or SeDBP difference ≥ 10mmHg
4. A history of hypertensive encephalopathy, unstable angina, transient ischemic attack, MI, or any type of revascularization procedure within the last 6 months
5. Heart failure, second- or third-degree heart block, significant arrhythmia or valvular heart disease
6. Significant cardiovascular, cerebrovascular, renal, gastrointestinal, or hematologic disease, at the discretion of investigator
7. Creatinine clearance<20mL/min and Renal artery stenosis, Renal Transplantation, Patients with only one kidney
8. Evidence of liver disease as indicated by alanine transaminase (ALT) and aspartate transaminase (AST) and/or total bilirubin ≥ 3 × the upper limit of normal (ULN)
9. Hyperkalemia (>5.5mmol/L)
10. Patients with sodium depletion is not correct or Patients with fluid depletion is not correct
11. Chronic inflammation
12. Patients with severe eye-related disorders (Retinal bleeding within 6 months, Blindness, Hypertension complications with Retinal micro-aneurysms)
13. Diabetes mellitus
14. Hematologic/oncologic, neurologic and psychiatric diseases
15. Females who were pregnant, breastfeeding, planning a pregnancy or who were of childbearing potential
16. Contraindications for amlodipine, losartan, olmesartan medoxomil, or other ARBs
17. With known allergic reaction, lack of response or contraindication to Angiotensin II receptor antagonists
18. Mean DBP > 110 mmHg
19. Patients who took antihyperlipidemic agents within 30 days
20. Subject who have participated in other clinical trial within the last one month
21. Any subjects who are unable to cooperate with protocol requirements and follow-up procedures or who are in medical condition that is not eligible to be entered in investigators' discretion