Kanagawa Combination Anti-hypertensive Therapy (K-CAT)

Inclusion Criteria: * Under treatment of hypertension with ARB monotherapy for more than one month. * systolic blood pressure more than 140mmHg and less than 160mmHg or diastolic blood pressure more than 90mmHg and less than 100mmHg in sitting position. * In diabetic or CKD patients, systolic blood pressure more than 130mmHg and less than 160mmHg or diastolic blood pressure more than 80mmHg and less than 100mmHg in sitting position. Exclusion Criteria: * uncontrolled hypertension (diastolic blood pressure \>120mmHg) * uncontrolled diabetes mellitus (HbA1c\>9.0%) * Acute myocardial infarction, stroke and other cardiovascular events within six months * The history of gout, or uric acid\>8.0mg/dl * Serum creatinine\>2.0mg/dl * sever liver dysfunction * Bilateral renovascular stenosis * secondary hypertension * malignant hypertension * uncontrolled arrhythmia * pregnancy or possibility of pregnancy * hypersensitivity to trial drug