Irbesartan/Hydrochlorothiazide (HCTZ) Combination Therapy as First Line Treatment for Severe Hypertension

The purpose of this clinical research is to learn if severe hypertension can be better controlled by initially treating with a combination of drugs (Irbesartan/HCTZ), in patients who are unlikely to achieve blood pressure (B/P) control with only one drug. In addition, the study will also evaluate the safety and tolerability of the drugs.

• Drug: Irbesartan/HCTZ
  Tablets, Oral, Irbesartan 150mg/HCTZ 12.5 mg, Once daily, 7 weeks.
  Other Name: Avapro
• Drug: Irbesartan monotherapy
  Tablets, Oral, 150 mg, Once daily, 7 weeks.
  Other Name: Avapro

• Experimental: A1
  Intervention: Drug: Irbesartan/HCTZ
• Active Comparator: A2
  Intervention: Drug: Irbesartan monotherapy

Inclusion Criteria:

• Men and women ages 18 and older;
• Willing to provide written informed consent;
• Must have uncontrolled hypertension defined as: currently untreated with a diastolic blood pressure greater than 110 mmHg OR currently receiving antihypertensive monotherapy with a diastolic blood pressure greater than 100 mmHg. Monotherapy is defined as treatment with one antihypertensive medication for at least four weeks; fixed combination therapy does not represent monotherapy;
• Must be willing to discontinue antihypertensive medication, if applicable;
• Women of childbearing potential (WOCBP) must be using an adequate method of contraception to avoid pregnancy throughout the study and for up to one week after the study in such a manner that the risk of pregnancy is minimized.
• WOCBP must have a negative serum or urine pregnancy test within 72 hours prior to the start of study medication.

Exclusion Criteria:

• Women who are pregnant or breastfeeding;
• Known or suspected secondary hypertension;
• Hypertension emergencies or stroke within the past 12 months;
• Heart attack, angina or bypass surgery within the past 6 months;
• Significant kidney disease;
• Significant liver disease;
• Systemic lupus erythematosus;
• Gastrointestinal disease or surgery that may interfere with drug absorption;
• Cancer during the past five years excluding localized squamous cell or basal cell carcinoma of the skin;
• Currently pregnant or lactating;
• Mental condition (psychiatric or organic cerebral disease) rendering the subject unable to understand the nature, scope, and possible consequences of the study;
• Drug or alcohol abuse within the last five years;
• Known allergy to irbesartan or diuretics.