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Antihypertensive Response to Losartan and Genetic Polymorphisms

This study has been completed.
Information provided by:
Merck Sharp & Dohme Corp. Identifier:
First received: February 5, 2008
Last updated: July 21, 2009
Last verified: July 2009
The purpose of this study is to evaluate the antihypertensive response of treatment with losartan with reference to genetic polymorphisms.

Condition Intervention
Drug: losartan potassium
Drug: Comparator: Hydrochlorothiazide

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Pharmacogenetic of the Antihypertensive Response to the Angiotensin II Blockers in Monotherapy or Associated to Hydrochlorothiazide

Resource links provided by NLM:

Further study details as provided by Merck Sharp & Dohme Corp.:

Primary Outcome Measures:
  • Blood pressure reduction with reference to genetic polymorphisms. [ Time Frame: Over 1 Year ]

Enrollment: 800
Study Start Date: March 2005
Study Completion Date: June 2009
Primary Completion Date: June 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1
Losartan 50 mg/day for 4 weeks, then doubled to losartan 100 mg/day in case of BP more than 140/90 mm Hg. HCTZ 25 mg will be added at week 8 if BP is more than 140/90 mm Hg. This last regimen will be continued until the end of the study (visit 9-week 48).
Drug: losartan potassium
Losartan 50 mg/day for 4 weeks, then doubled to losartan 100 mg/day (in case of BP more than 140/90 mm Hg.) Continued until the end of the study (visit 9-week 48).
Drug: Comparator: Hydrochlorothiazide
Hydrochlorothiazide 25 mg will be added at week 8 if BP is more than 140/90 mm Hg. This last regimen will be continued until the end of the study (visit 9-week 48).


Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Both gender less than 60 years old, with mild-moderate hypertension (SBP greater than and DBP equal or greater than 90 mmhg, BP < 180/110)
  • Never treated for hypertension or who have taken antihypertensive agents sporadically (not more than 15 days total therapy) but not in the 30 days prior to the first visit
  • Patient in therapeutic wash out for 6 months
  • Patient is asymptomatic, absence of significant concomitant diseases, except for non-familial hypercholesterolemia, absence of systemic diseases
  • Women with menopause not treated with hormone replacement therapy or women of reproductive age who do not make use of estro-progestagen agents but who use another safe contraceptive method
  • BMI < 30 for men and < 28 for women

Exclusion Criteria:

  • Secondary or malignant hypertension, Na <130 mmol/l, K >5,5 mmol/l, or < 3,0 mmol/l
  • Cardiac disease such as ischemic, HF, arrhythmia, cardiac surgery
  • Pregnant, breast feeding
  • History of nephropathy, metabolic disease, liver disease
  • Alcohol or drug abuse
  • History of angioedema
  • Has a known hypersensibility to study drug(s)
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Please refer to this study by its identifier: NCT00617877

Sponsors and Collaborators
Merck Sharp & Dohme Corp.
Study Director: Medical Monitor Merck Sharp & Dohme Corp.
  More Information

Additional Information:
Responsible Party: Executive Vice President, Clinical and Quantitative Sciences, Merck & Co., Inc. Identifier: NCT00617877     History of Changes
Other Study ID Numbers: 2007_035
Study First Received: February 5, 2008
Last Updated: July 21, 2009

Additional relevant MeSH terms:
Antihypertensive Agents
Anti-Arrhythmia Agents
Angiotensin II Type 1 Receptor Blockers
Angiotensin Receptor Antagonists
Molecular Mechanisms of Pharmacological Action
Natriuretic Agents
Physiological Effects of Drugs
Sodium Chloride Symporter Inhibitors
Membrane Transport Modulators processed this record on May 25, 2017