To evaluate drug-drug interaction between fimasartan and hydrochlorothiazide.

Fimasartan (BR-A-657-K), a selective blocker of AT1 receptor subtype, showed the rapid and potent antihypertensive effect in many hypertensive models.

Phase I study, Fimasartan (BR-A-657-K) 20 mg ~ 480 mg single dosing with healthy subjects, demonstrated that the Fimasartan (BR-A-657-K) was very safe and well tolerated. Another phase I study, Fimasartan (BR-A-657-K) 120mg and 360mg dosing for 7 days, also showed that Fimasartan (BR-A-657-K) was safe and tolerable though one temporal adverse event was observed in high dose.

A open-labeled, multiple-dosing, crossover, parallel Clinical Study to Evaluate drug-drug interaction between fimasartan and hydrochlorothiazide.

34 male healthy volunteers were enrolled during 2 months.

In part A, 240 mg of fimasartan per day was taken for 1 week. After 7 day washout period, 240 mg of fimasartan and 25mg of hydrochlorothiazide per day were taken for 1 week. Then blood and urine samples were collected 0, 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12 and 24 hours at 7 day and 21 day.

In part B, 25 mg of hydrochlorothiazide per day was taken for 1 week. After 7 day washout period, 240 mg of fimasartan and 25mg of hydrochlorothiazide per day were taken for 1 week. Then blood and urine samples were collected 0, 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12 and 24 hours at 7 day and 21 day.

Inclusion Criteria:

• age: 20 - 45 years
• sex: male
• body weight: greater than 55 kg
• written informed consent

Exclusion Criteria:

• known allergy to Fimasartan and hydrochlorothiazide
• existing cardiac or hematological diseases
• existing hepatic and renal diseases
• existing gastrointestinal diseases
• acute or chronic diseases which could affect drug absorption or metabolism
• history of any serious psychological disorder
• positive drug or alcohol screening
• smokers of 10 or more cigarettes per day 3 month ago
• participation in a clinical trial during the last 2 months prior to the start of the study