Evaluation of Effect of Combination With Telmisartan and Hydrochlorothiazide in Hypertensives Uncontrolled on Amlodipine

Study Overview
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Brief Summary
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The purpose of this study is to compare depressor effect and safety between combination therapy with telmisartan plus low-dose hydrochlorothiazide and amlodipine in hypertensive patients.

Detailed Description
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In hypertensive patients whose blood pressure (BP) does not reach less than 140/90 mmHg with 5mg/day of amlodipine are divided the following two groups and BP response, laboratory data, and adverse effects are compared. Group 1: 12 week combination therapy with telmisartan plus low-dose hydrochlorothiazide. Group 2: Amlodipine is continuously administered.

Official Title
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ONgoing Evaluation of Depressor Effect And Safety of Combination Therapy With Telmisartan and Low-dose Hydrochlorothiazide in Patients With Hypertension Uncontrolled on Amlodipine Treatment

Conditions
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Essential Hypertension

Intervention / Treatment
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* Drug: telmisartan plus hydrochlorothiazide
* Device: Amlodipine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 5 mg/day of amlodipine is administered for more than 3 months Systolic or diastolic blood pressure >= 140/90 mmHg (more than 2 times measurements at outpatient clinic before start of the study) Outpatients Exclusion Criteria: Secondary hypertension including renovascular hypertension with single kidney or bilateral stenosis Administration of antihypertensives other than amlodipine Cardiovascular disease (cerebral hemorrhage, cerebral infarction, TIA, angina, myocardial infarction, acute renal failure) occurs less than 6 months before start of the study Serum creatinine >= 2.0 mg/dl Severe hypertension (systolic or diastolic blood pressure >= 180/110 mmHg) or malignant hypertension (hypertensive organ damage is rapidly developing) Chronic heart failure (NYHA class>=III to VI) Contraindication of telmisartan or hydrochlorothiazide Hyper- (>= 5.5 mEq/L) or hypo- (<=3.5 mEq/l) potassemia Untreated hyperuricemia or uncontrolled hyperuricemia (serum uric acid >= 8.0 mg/dl) Diabetic patients who require insulin therapy, uncontrolled diabetic patients (hemoglobin A1c >=9.0%), or patients who possess the risk of hypoglycemic attack Patients inadequate for the study

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: telmisartan plus low-dose hydrochlorothiazide<br>12 week combination therapy with telmisartan plus low-dose hydrochlorothiazide | Drug: telmisartan plus hydrochlorothiazide<br>* Combination therapy with telmisartan (40 mg/day) plus hydrochlorothiazide (12.5 mg/day): If blood pressure is not reach to lower than 140/90 mmHg, dose of telmisartan can be increased to 80 mg/day<br>|
| Active Comparator: Amlodipine<br>Amlodipine is continuously administered. | Device: Amlodipine<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in office blood pressure |  | After 12 week treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 1) Home blood pressure in early morning and before going to bed 2) Changes in uric acid, total cholesterol, HDL cholesterol, LDL cholesterol, triglyceride, fasting plasma glucose (only in diabetic patients), hemoglobin A1c (only in diabetic patients |  | After 12 week treatment |