• Compare the reduction in office BP following a 4-week regimen of irbesartan / hydrochlorothiazide versus irbesartan
• Compare the response rate (defined as office SBP/DBP reduce more than 10mmHg from week 0) of patients after 4-week and 8-week regimen of irbesartan/hydrochlorothiazide versus irbesartan
• Compare the proportion of patients requiring titration after 4-week regimen of irbesartan/hydrochlorothiazide versus irbesartan
• Ascertain the safety and tolerability of irbesartan/hydrochlorothiazide versus irbesartan when administered once daily.

Study Objectives :

• To demonstrate the reduction in office Blood Pressure following a 8-week regimen of irbesartan / hydrochlorothiazide using irbesartan as a reference.
• To demonstrate the reduction in office Blood Pressure after 4-week regimen of irbesartan / hydrochlorothiazide using irbesartan as a reference.
• To compare the response rate (defined as office Systolic Blood Pressure/Diastolic Blood Pressure reduce more than 10mmHg from Week 0) of patients after 4-week and 8-week regimen of irbesartan / hydrochlorothiazide versus irbesartan.
• To compare the proportion of patients requiring titration after 4-week regimen of irbesartan/hydrochlorothiazide versus irbesartan
• To ascertain the safety and tolerability of irbesartan / hydrochlorothiazide versus irbesartan when administered once daily

• Drug: Irbesartan/hydrochlorothiazide
• Drug: Irbesartan

Inclusion Criteria:

• Patients with mild to moderate hypertension with office Diastolic Blood Pressure (DBP) 90-109 mmHg and/or Systolic Blood Pressure (SBP) 140-179 mmHg
• All women of child-bearing potential must have negative urine pregnancy tests within a week prior to initiation of therapy

Exclusion Criteria:

• females who are pregnant or breast feeding
• office DBP ≥ 110 mmHg or office SBP ≥ 180 mmHg

• history of significant cardiovascular diseases which includes:

  • acute myocardial infarction within six months or any ischemic heart disease requiring medication.
  • cerebrovascular disease

• history of significant renal diseases including:

  • serum creatinine > 3.0 mg/dl.
  • creatinine clearance < 30 ml/min.
• severe biliary cirrhosis and cholestasis
• refractory hypokalemia, hypercalcemia
• history of autoimmune disease, collagen vascular disease, multiple drug allergies, bronchospastic disease or other malignancies requiring current medication

• hepatic disease as indicated by any of the following:

  • SGOT or SGPT >3 x upper limit of normal.
  • Serum bilirubin > 2 x upper limit of normal.
• any other condition or therapy that, in the investigator's opinion, or as indicated in the product(s) label may pose a risk to the patient or interfere with the study objectives.
• any other investigational drug given within 30 days of initiation of therapy, and participation in other clinical studies while enrolled in this protocol.

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.