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

NCT06440252 | Completed Phase 3

• 1 other identifier: ALVCIR
• Study Type: interventional
• Target: 35
• Locations: 1 country
• Sites: 1

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.

Conditions

Circulatory; Change

Outcome Measures

Primary Outcomes (1)

• Change in Diastolic blood pressure (arm)

  Change in Diastolic blood pressure (arm) as measured by blood pressure machine

  Baseline, week 4, week 8, week 11

Secondary Outcomes (21)

• Change in Systolic blood pressure (arm)

  Baseline, week 4, week 8, week 11

• Change in Peripheral systolic and diastolic blood pressure (leg)

  Baseline, week 4, week 8, week 11

• Change in HGB

  Baseline, week 4, week 8, week 11

• Change in WBC

  Baseline, week 4, week 8, week 11

• Change in RBC

  Baseline, week 4, week 8, week 11

Study Arms (2)

Grape Seed Extract

ACTIVE COMPARATOR

Grape seed extract 600mg per day - 1 capsule per day

Drug: Grape Seed Extract

Maltodextrin

PLACEBO COMPARATOR

Maltodextrin - 1 capsule per day

Drug: Maltodextrin

Interventions

Grape Seed Extract DRUG

One daily dose of 1 capsule containing 600mg grape seed extract

Grape Seed Extract

Maltodextrin DRUG

One daily dose of 1 capsule

Maltodextrin

Eligibility Criteria

• Age: 25 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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

You may not qualify if:

• 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
• Participated in another trial in the past 1 month
• Any participant that begins taking antiplatelet medication during the trial will be excluded from the study

Sponsors & Collaborators

• RDC Clinical Pty Ltd: lead

Study Sites (1)

RDC Clinical Pty Ltd

Brisbane, Queensland, 4006, Australia

Location

MeSH Terms

Interventions

Grape Seed Extract; maltodextrin

Intervention Hierarchy (Ancestors)

Plant Extracts; Plant Preparations; Biological Products; Complex Mixtures; Pharmaceutical Preparations

Study Officials

• Amanda Rao, PhD

  RDC Clinical Pty Ltd

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 17, 2024
• First Posted: June 3, 2024
• Study Start: October 31, 2024
• Primary Completion: December 31, 2025
• Study Completion: December 31, 2025
• Last Updated: March 6, 2026

Record last verified: 2025-07

Locations

AU (1)