Sympathetic Regulation of Large Artery Stiffness in Humans With ISH

NCT04423627 | Completed Early Phase 1 FDA Drug

• 1 other identifier: 202004244
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 2

Brief Summary

Stiffening of your blood vessels, particularly the large vessels from your heart (called the aorta and carotids) you age contributes to the development of cardiovascular disease (CVD) such as heart attack and stroke. Nerve activity from your brain to your body also increases with advancing age but it is unknown if this nerve activity contributes directly to the stiffening on your blood vessels in older adults in addition to high blood pressure. Therefore, successful completion of the proposed aims will have a significant clinical impact by identifying if nerve activity from your brain could be a novel target for therapies that would lower stiffness of the aorta and carotid arteries in older adults.

Conditions

Hypertension, Systolic; Stiffness, Aortic

Outcome Measures

Primary Outcomes (1)

• Change in carotid-femoral pulse wave velocity

  Aortic stiffness

  Baseline and after 4 weeks

Secondary Outcomes (3)

• Change in carotid distensibility index

  Baseline and after 4 weeks

• Change in carotid flow pulsatility index

  Baseline and after 4 weeks

• Change in carotid intimal medial thickness (IMT)

  Baseline and after 4 weeks

Study Arms (3)

Clonidine

EXPERIMENTAL

0.2 mg/day oral

Drug: Clonidine

Hydrochlorothiazide

ACTIVE COMPARATOR

37.5 mg/day oral

Drug: Hydrochlorothiazide

Placebo

PLACEBO COMPARATOR

Placebo

Drug: Placebo

Interventions

Clonidine DRUG

Clonidine 0.2 mg/day oral tablet

Clonidine

Hydrochlorothiazide DRUG

Hydrochlorothiazide 37.5 mg/day oral tablet

Hydrochlorothiazide

Placebo DRUG

Placebo

Placebo

Eligibility Criteria

• Age: 60 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• age 60-85
• non-smoking
• clinically healthy
• untreated or treated stage 1 isolated systolic hypertension (ISH) (systolic BP 130-139 mmHg; diastolic BP \<90 mmHg) or stage 2 ISH (systolic BP 140-159 mmHg; diastolic BP \<90 mmHg) per 2017 AHA/ACC hypertension guidelines
• if subject is on antihypertensive medications, they will stop taking medication for a one-week washout period after Visit 1 before they return for Visit 2. They will come in at day 3 and day 7 of the one-week washout for a BP reading, to confirm that systolic BP is \<160 mmHg.

You may not qualify if:

• no history of cardiovascular disease (e.g., myocardial infarction, bypass surgery, angioplasty/stent, heart failure, cardiomyopathy, pacemaker/defibrillator, peripheral artery disease), pulmonary disease, liver disease, Type I or II diabetes, cancer (treated by chemotherapy and/or radiation), psychiatric illness, on aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs).
• aspirin, NSAIDs, vitamins, herbal supplements, omega-3-fatty acids will have to discontinue for at least 1 week before participation and remain discontinued during the study.
• blood thinners, serotonin reuptake inhibitors (SSRIs), or PDE5 inhibitors will also be excluded.
• Women must be postmenopausal for at least 6 months (surgical or natural) and not currently on hormone replacement therapy.
• Subjects not on antihypertensive will not be eligible if their resting clinic systolic BP is \<130 mmHg or \>160 mmHg and diastolic BP \>90 mmHg.

Sponsors & Collaborators

• University of Iowa: lead

Study Sites (2)

Amy Stroud

Iowa City, Iowa, 52240, United States

Location

University of Iowa

Iowa City, Iowa, 52242, United States

Location

MeSH Terms

Conditions

Isolated Systolic Hypertension

Interventions

Clonidine; Hydrochlorothiazide

Condition Hierarchy (Ancestors)

Essential Hypertension; Hypertension; Vascular Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Imidazolines; Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Chlorothiazide; Benzothiadiazines; Sulfonamides; Sulfones; Sulfur Compounds; Organic Chemicals; Thiazides; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Study Officials

• Gary Pierce, PhD

  University of Iowa

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: Randomized, placebo controlled, parallel design

Study Record Dates

• First Submitted: June 5, 2020
• First Posted: June 9, 2020
• Study Start: June 1, 2021
• Primary Completion: July 31, 2025
• Study Completion: July 31, 2025
• Last Updated: August 8, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (2)