Effectiveness of a Grape Seed Extract on Circulatory Measures in Healthy Adults

Phase 3

Recruiting

• Conditions: Circulatory; Change
• Interventions: Drug: Maltodextrin; Drug: Grape Seed Extract

• Registration Number: NCT06440252
• Lead Sponsor: RDC Clinical Pty Ltd

Brief Summary

This is a randomized, double-blind, placebo-controlled, 2 arm crossover study conducted over 11 weeks, with participants randomised to a product for 4 weeks, followed by a 3-week washout period before completing the second product for 4 weeks, to study the effectiveness of a grape seed extract on circulatory measures in healthy adults.

Detailed Description

Not available

Study Timeline

• Status Verified: 2024-05
• Study First Submitted: 2024-05-17
• Study First Submitted QC: 2024-05-28
• Study First Posted: 2024-06-03
• Study Start: 2024-10-31
• Last Update Submitted: 2024-12-03
• Last Update Posted: 2024-12-05
• Primary Completion: 2025-03-31
• Study Completion: 2025-06-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 150

Inclusion Criteria

• Adults 25 years or older
• Generally healthy
• BMI 18 - 35kg/m2
• Able to provide informed consent
• Have prehypertensive blood pressure (systolic 120-139 mmHg and/or diastolic 80-89 mmHg)
• Agree to not change current diet and/or exercise frequency or intensity during entire study period
• Agree to not participate in another clinical trial while enrolled in this trial

Exclusion Criteria

• Those with a history of myocardial infarction, angina or bleeding disorders

• Those who have uncontrolled thyroid diseases

• Currently taking dietary supplements for circulation (e.g. fatty acids, CoQ10, L-arginine, red ginseng, ginseng, natto, ginkgo) or use of these in the last 1 month

• Currently taking inflammation or circulatory associated medications (e.g. Pentoxifylline and vasodilators like nitroglycerin) or use of these in the last 1 month

• Currently taking statins medication including atorvastatin (e.g. Lipitor, Lorstat), fluvastatin (e.g. Lescol or Vastin), pravastatin (e.g. Pravachol, Cholstat), rosuvastatin (e.g. Cavstat, Crestor) or simvastatin (e,g, Lipex, Zocor, Zimstat).

• Currently taking Coumadin, Marevan (Warfarin), Heparin, Dalteparin, Enoxaparin or other anticoagulation therapy, or substrates of P-glycoprotein including (but not limited to) calcium channel blockers, cyclosporin, digoxin, erythromycin and protease inhibitors(1).

• Have a serious illness(2) e.g. mood disorders such as bipolar disorder, neurological disorders such as MS, kidney disease, liver disease or heart conditions

• Have an unstable illness(3) (i.e., changing medication/treatment)

• Malignancy or treatment for malignancy within the previous 2 years (this excludes non-melanoma (e.g. BCC and SCC) skin cancers not requiring radiation or chemotherapy)

• Active smokers, nicotine use or drug (prescription or illegal substances) abuse

• Chronic past and/or current alcohol use (>14 alcoholic drinks week)

• Allergic to any of the ingredients in active or placebo formula

• Pregnant or lactating woman or women trying to conceive

• Any condition which in the opinion of the investigator makes the participant unsuitable for inclusion

• Participated in another trial in the past 1 month

  1. Any participant that begins taking antiplatelet medication during the trial will be excluded from the study
  2. A serious illness is a condition that carries a risk of mortality, negatively impacts quality of life and daily function and/or is burdensome in symptoms and/or treatments.
  3. An unstable illness is any illness that is currently not being treated with a stable dose of medication or is fluctuating in severity.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Maltodextrin	Maltodextrin	Maltodextrin - 1 capsule per day
Grape Seed Extract	Grape Seed Extract	Grape seed extract 600mg per day - 1 capsule per day

Primary Outcome Measures

Name	Time	Method
Change in Diastolic blood pressure (arm)	Baseline, week 4, week 8, week 11	Change in Diastolic blood pressure (arm) as measured by blood pressure machine

Secondary Outcome Measures

Name	Time	Method
Change in Peripheral systolic and diastolic blood pressure (leg)	Baseline, week 4, week 8, week 11	Change in Peripheral systolic and diastolic blood pressure (leg) as measured by blood pressure machine
Change in HGB	Baseline, week 4, week 8, week 11	Change in HGB as measured by FBC via blood test
Change in WBC	Baseline, week 4, week 8, week 11	Change in WBC as measured by FBC via blood test
Change in RBC	Baseline, week 4, week 8, week 11	Change in RBC as measured by FBC via blood test
Change in Platelet Aggregation	Baseline, week 4, week 8, week 11	Change in Platelet Aggregation as measured by FBC via blood test
Change in Systolic blood pressure (arm)	Baseline, week 4, week 8, week 11	Change in Systolic blood pressure (arm) as measured by blood pressure machine
Change in (endothelial nitric oxide synthase) eNOS	Baseline, week 4, week 8, week 11	Change in eNOS as measured via blood test
Change in endogenous nitric oxide (NO)	Baseline, week 4, week 8, week 11	Change in NO as measured via blood test
Change in Tibial artery structure	Baseline, week 4, week 8, week 11	Change in Tibial artery structure via Laser Doppler Flowmetry
Change in blood flow of the right leg	Baseline, week 4, week 8, week 11	Change in blood flow of the right leg via Laser Doppler Flowmetry
Change in oxygen saturation	Baseline, week 4, week 8, week 11	Change in oxygen saturation as measured by pulse oximeter
Change in resting pulse rate	Baseline, week 4, week 8, week 11	Change in resting pulse rate as digital blood pressure and resting pulse rate machine
Change in weight	Baseline, week 4, week 8, week 11	Change in weight as measure by digital scales
Change in Body Mass Index (BMI)	Baseline, week 4, week 8, week 11	Change in BMI as measured by weight and height calculation
Change in waist and hip circumference	Baseline, week 4, week 8, week 11	Change in waist and hip circumference as measured by tape measure
Change in 36-Item Short Form Health Survey (SF-36)	Baseline, week 4, week 8, week 11	Change in 36-Item Short Form Health Survey (SF-36) as self-reported
Change in E/LFT	Baseline, week 4, week 8, week 11	Change in E/LFT as measured via blood test
Change in triglycerides	Baseline, week 4, week 8, week 11	Change in triglycerides as measured via blood test
Change in cholesterol	Baseline, week 4, week 8, week 11	Change in cholesterol as measured via blood test
Change in blood glucose	Baseline, week 4, week 8, week 11	Change in blood glucose as measured via blood test
Change in adverse events	Baseline, week 4, week 8, week 11	Change in adverse events as reported by participant

Trial Locations

Locations (1)

RDC Clinical Pty Ltd; 🇦🇺 Brisbane, Queensland, Australia