CClinicalTrials.gg
CompletedNCT00675987Updated Sep 6, 2018Results posted

A Randomized Clinical Trial To Study Losartan On Endothelial Dysfunction and Insulin Resistance In Obese Patients

A Phase 4 interventional study of losartan and Placebo control in Obesity, Hypertension and Hyperglycemia, sponsored by Brigham and Women's Hospital. Completed at 9 sites in United States. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2018-09-06.

Sponsored by Brigham and Women's Hospital · Phase 4, Interventional, and Other

Phase
Phase 4
Study type
Interventional
Enrollment
53
Allocation
Randomized
Ages
18 Years to 75 Years
Sex
All
01

Study summary

The main purposes of this study are to find out if the study drug losartan (Cozaar) or placebo ("sugar pill") has an effect on insulin sensitivity (how your body responds to insulin) and to measure the effect of the study drug losartan or placebo on how the arteries in your arm dilate (enlarge to carry more blood).

We hope to learn if taking losartan changes the amount of certain proteins in the blood that effect blood vessel function.

Losartan is approved by the US FDA to treat high blood pressure. It will take approximately 4 months for you to complete this study.

02

Conditions studied

  • Obesity
  • Hypertension
  • Hyperglycemia

Keywords

  • Impaired Fasting Glucose FPG >100-<126 mg/dL
03

In context

Insulin Resistance

1,960 studies on the registry are indexed under Insulin Resistance; 306 are open to participants now.

This study's enrollment of 53 is above the median of 40 across 1,536 interventional studies indexed under Insulin Resistance.

Browse Insulin Resistance studies →

Lead sponsor

Brigham and Women's Hospital is the lead sponsor of 1,236 studies on the registry; 224 are open to participants now.

Of its 116 completed or terminated interventional studies of FDA-regulated products, 64 (55%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 75 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Currently taking 1 or no antihypertensive medication
  • Male and female between 18 and 75 years of age
  • Mean trough sitting diastolic blood pressure (SiDBP) ≥80 and \< 100 mm Hg
  • Mean trough sitting systolic blood pressure (SiSBP) ≥120 and \<160 mm Hg
  • Non-diabetic patients with fasting plasma glucose ≥100 mg/dL and \<126 mg/dL
  • Body mass index (BMI) >30 and \<40
  • Waist circumference >40 inches in males, > 35 inches in females
  • A patient who is of reproductive potential and agrees to remain abstinent or use acceptable methods of birth control (intrauterine device (IUD), diaphragm with spermicide, contraceptive sponge, condom, hormonal contraception, vasectomy) within the projected duration of the study

Exclusion criteria

Exclusion Criteria:

  • Secondary hypertension of any etiology (renal artery stenosis, coarctation of the aorta or pheochromocytoma, hypertension induced by oral contraceptives)
  • History of malignant hypertension
  • Any clinically significant renal disease including single functioning kidney, and known history of anuria. Any severe renal impairment, as manifested by serum creatinine more than 1.5 mg/dL, or proteinuria >2+ by urine dipstick
  • Known sensitivity or intolerance to angiotensin II receptor antagonists
  • Type I or II diabetes
  • Inability or unwillingness to abstain from taking prohibited medications during the study period
  • History of myocardial infarction (MI), percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), congestive heart failure (CHF), unstable angina, transient ischemic attack (TIA), or cerebrovascular accident (CVA)
  • Concomitant cardiac conditions that would make it unsafe to participate in the trial (e.g., clinically significant atrioventricular (AV) conduction disturbance, atrial flutter, atrial fibrillation, potentially life-threatening ventricular arrhythmias, decompensated valvular disease, presence of hemodynamically significant obstructive valvular disease, or cardiomyopathy)
  • History of angioedema and/or organ damage from hypertension
  • Serum potassium \< 3.5 or > 5.5 mEq/L
  • Any clinically significant laboratory value which in the investigator's judgment could be clinically significant to the outcome of this study.
  • History of clinically important gastrointestinal resection or malabsorption
  • Patient with a history or current evident of any condition, therapy, lab abnormality, or other circumstance that might confound the results of the study, or interfere with the patient's participation for the full duration of the study, such that it is not in the best interest of the patient to participate. (Including but not limited to: recent or current alcoholism, drug abuse within the prior 2 years, mental or legal incapacitation, any disease which could reasonably be expected to be fatal or life-threatening, or a history of malignancy ≤ 5 years prior to signing informed consent.)
  • Currently participating or has participated in a study with an investigational compound or device within 30 days of signing informed consent.
  • Inability to be taken off all current antihypertensive medication and placed on placebo for up to 12 weeks.
  • Unwillingness or unlikely to adhere to the study procedures, keep appointments, or is planning to relocate during the study.
  • Arm circumference great than 52 cm
  • Smokers or former smokers who have quite less than 1 year prior to Visit 1
  • Anemia (Hemoglobin \< 11)
  • Allergy to latex
  • Deformed hands and/or fingers that would interfere with the collection of pulse volume amplitude measurements
  • History of Raynaud's disease or any other vascular condition
  • Bilateral mastectomy
  • Aortic stenosis
  • Patient is taking high doses of antioxidant supplements (vitamins, minerals, or other)
05

Study design

Phase
Phase 4
Primary purpose
Other
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
53 participants (actual)

Study arms

  • Active comparator
    Losartan

    Losartan 100 mg 1 tab po QD

    Drug: losartan

  • Placebo comparator
    Placebo

    Placebo 1 tab po QD

    Drug: Placebo control

Interventions

  • Druglosartan

    losartan 100 mg tablets 1 tab po QD

    Also known as: Cozaar

  • DrugPlacebo control

    Placebo 1 po QD

06

What researchers measure

Primary outcomes

  1. Insulin Sensitivity Utilizing the Euglycemic Hyperinsulinemic Clamp

    Insulin clamp derived insulin sensitivity, as insulin stimulated glucose disposal corrected for steady state insulin level.

    Time frame: baseline, 8 weeks

  2. Insulin Sensitivity Utilizing Endothelial Function as Assessed by Pulse Volume Amplitude

    Endothelial function assessed as the ratio of pulse volume amplitude after compared with before a reactive hyperemia stimulus, measured by peripheral (fingertip) arterial tonometry. Reported values indicate the percentage change from Baseline in the ratio of pulse volume amplitude after compared to before the reactive hyperemia stimulus.

    Time frame: baseline, 8 weeks

Secondary outcomes

  1. Change in Urine Albumin/Creatine

    Urine was obtained to assess for the presence of microalbuminuria.

    Time frame: baseline, 8 weeks

  2. Change in hsCRP (High-sensitivity C-reactive Protein)

    hsCRP (high-sensitivity C-reactive protein) is a marker of inflammation

    Time frame: baseline, 8 weeks

  3. Change in VCAM-1(Vascular Cell-adhesion Molecule-1)

    VCAM-1 is an immunoglobulin-like adhesion molecule expressed on activated endothelial cells.

    Time frame: baseline, 8 weeks

  4. Change in MCP-1 (Monocyte Chemoattractant Protein-1)

    MCP-1 is one of the key chemokines that regulate migration and infiltration of monocytes/macrophages.

    Time frame: baseline, 8 weeks

  5. Change in Ox-LDL (Oxidized Low-density Lipoprotein)

    ox-LDL measures protein damage due to the oxidative modification of the ApoB subunit on LDL cholesterol.

    Time frame: baseline, 8 weeks

  6. Change in F2-isoprostanes

    F2-isoprostanes is a marker of oxidative stress.

    Time frame: baseline, 8 weeks

  7. Change in E-selectin

    E-selectin is expressed on inflamed endothelial cells in response to treatment with inflammatory cytokines.

    Time frame: baseline, 8 weeks

07

Results

Posted Aug 21, 2012

Participant flow

Participant flow — Overall Study
MilestoneLosartan 100 mg 1 Tab po QDPlacebo 1 Tab po QD
Started2627
Completed2627
Not completed00

Outcome measures

PrimaryInsulin Sensitivity Utilizing the Euglycemic Hyperinsulinemic Clamp

Insulin clamp derived insulin sensitivity, as insulin stimulated glucose disposal corrected for steady state insulin level.

Time frame:
baseline, 8 weeks
Reported as:
Mean · mg/kg/min
Insulin Sensitivity Utilizing the Euglycemic Hyperinsulinemic Clamp
mg/kg/minPlaceboLosartan
Insulin Sensitivity Utilizing the Euglycemic Hyperinsulinemic Clamp5.3 ± 4.52.8 ± 1.7
PrimaryInsulin Sensitivity Utilizing Endothelial Function as Assessed by Pulse Volume Amplitude

Endothelial function assessed as the ratio of pulse volume amplitude after compared with before a reactive hyperemia stimulus, measured by peripheral (fingertip) arterial tonometry. Reported values indicate the percentage change from Baseline in the ratio of pulse volume amplitude after compared to before the reactive hyperemia stimulus.

Time frame:
baseline, 8 weeks
Reported as:
Mean · percentage change
Insulin Sensitivity Utilizing Endothelial Function as Assessed by Pulse Volume Amplitude
percentage changePlaceboLosartan
Insulin Sensitivity Utilizing Endothelial Function as Assessed by Pulse Volume Amplitude1.76 ± 0.72.11 ± 0.7
SecondaryChange in Urine Albumin/Creatine

Urine was obtained to assess for the presence of microalbuminuria.

Time frame:
baseline, 8 weeks
Reported as:
Mean · mg/mmol
Change in Urine Albumin/Creatine
mg/mmolPlaceboLosartan
Change in Urine Albumin/Creatine0.4 (-0.1 to 0.9)0.2 (-0.3 to 0.8)
SecondaryChange in hsCRP (High-sensitivity C-reactive Protein)

hsCRP (high-sensitivity C-reactive protein) is a marker of inflammation

Time frame:
baseline, 8 weeks
Reported as:
Mean · percentage change
Change in hsCRP (High-sensitivity C-reactive Protein)
percentage changePlaceboLosartan
Change in hsCRP (High-sensitivity C-reactive Protein)-10 (-32 to 20)-34 (-50 to -13)
SecondaryChange in VCAM-1(Vascular Cell-adhesion Molecule-1)

VCAM-1 is an immunoglobulin-like adhesion molecule expressed on activated endothelial cells.

Time frame:
baseline, 8 weeks
Reported as:
Mean · ng/ml
Change in VCAM-1(Vascular Cell-adhesion Molecule-1)
ng/mlPlaceboLosartan
Change in VCAM-1(Vascular Cell-adhesion Molecule-1)29 (-20 to 79)-21 (-70 to 28)
SecondaryChange in MCP-1 (Monocyte Chemoattractant Protein-1)

MCP-1 is one of the key chemokines that regulate migration and infiltration of monocytes/macrophages.

Time frame:
baseline, 8 weeks
Reported as:
Mean · pg/ml
Change in MCP-1 (Monocyte Chemoattractant Protein-1)
pg/mlPlaceboLosartan
Change in MCP-1 (Monocyte Chemoattractant Protein-1)-37 (-80 to 6.8)-24 (-65 to 18)
SecondaryChange in Ox-LDL (Oxidized Low-density Lipoprotein)

ox-LDL measures protein damage due to the oxidative modification of the ApoB subunit on LDL cholesterol.

Time frame:
baseline, 8 weeks
Reported as:
Mean · units/l
Change in Ox-LDL (Oxidized Low-density Lipoprotein)
units/lPlaceboLosartan
Change in Ox-LDL (Oxidized Low-density Lipoprotein)-2.0 (-8.1 to 4.1)-5.5 (-11.9 to 0.9)
SecondaryChange in F2-isoprostanes

F2-isoprostanes is a marker of oxidative stress.

Time frame:
baseline, 8 weeks
Reported as:
Mean · ng/mg of creatinine
Change in F2-isoprostanes
ng/mg of creatininePlaceboLosartan
Change in F2-isoprostanes0.4 (-0.9 to 1.6)0.9 (-0.4 to 2.2)
SecondaryChange in E-selectin

E-selectin is expressed on inflamed endothelial cells in response to treatment with inflammatory cytokines.

Time frame:
baseline, 8 weeks
Reported as:
Mean · ng/ml
Change in E-selectin
ng/mlPlaceboLosartan
Change in E-selectin-1.6 (-4.5 to 1.3)-0.6 (-3.5 to 2.3)

Adverse events

Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Losartan—0/26 (0%)0/26 (0%)
Placebo—0/27 (0%)0/27 (0%)

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)Losartan 100 mg 1 Tab po QDPlacebo 1 Tab po QDTotal
<=18 years000
Between 18 and 65 years262753
>=65 years000
Age, Continuous
Age, Continuous(years)Losartan 100 mg 1 Tab po QDPlacebo 1 Tab po QDTotal
Mean51.1 ± 10.553.8 ± 8.352.5 ± 9.5
Sex: Female, Male
Sex: Female, Male(Participants)Losartan 100 mg 1 Tab po QDPlacebo 1 Tab po QDTotal
Female141226
Male121527
Region of Enrollment
Region of Enrollment(participants)Losartan 100 mg 1 Tab po QDPlacebo 1 Tab po QDTotal
United States262753
08

Study locations

9 sites
  • CAVS Clinical Research Center
    Little Rock, Arkansas 72205, United States
  • VA San Diego Health Care System
    San Diego, California 92161, United States
  • University of Miami Diabetes Research Institute
    Miami, Florida 33136, United States
  • Indiana University School of Medicine
    Indianapolis, Indiana 46202, United States
  • Brigham and Women's Hospital Cardiovascular Division
    Boston, Massachusetts 02115, United States
  • St. Lukes Roosevelt Hospital
    New York, New York 10025, United States
  • University of Pennsylvania School of Medicine
    Philadelphia, Pennsylvania 19104, United States
  • University of Texas SW Medical Center at Dallas
    Dallas, Texas 75390, United States
  • Hypertension Clinical Pharmacology Baylor Clinic
    Houston, Texas 77030, United States
09

References and documents

Publications

  • Perlstein TS, Henry RR, Mather KJ, Rickels MR, Abate NI, Grundy SM, Mai Y, Albu JB, Marks JB, Pool JL, Creager MA. Effect of angiotensin receptor blockade on insulin sensitivity and endothelial function in abdominally obese hypertensive patients with impaired fasting glucose. Clin Sci (Lond). 2012 Feb;122(4):193-202. doi: 10.1042/CS20110284. PubMed 21861845 ↗
10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 6, 2018, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT00675987
Lead sponsor
Brigham and Women's Hospital
Collaborators
Merck Sharp & Dohme LLC
Responsible party
Mark Alan Creager, MD (Principal Investigator, Brigham and Women's Hospital) — Principal investigator
First posted
May 12, 2008
Start date
May 2007
Primary completion
Dec 2008
Completion
Dec 2008
Results posted
Aug 21, 2012
Last update
Sep 6, 2018

Study contacts

Mark A Creager, MD
principal investigator · Brigham and Women's Hospital

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Aug 2018. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion