Cardiovascular Internal Medicine Unit, IRCCS University Hospital of Bologna, Bologna, Italy
Bologna, Bo, 40100, Italy
Location status: Recruiting
Recruiting
NCT Number: NCT07090876
Hemodynamic Effects of a Standardized Grape Seed Extract Supplementation
The purpose of this study is to evaluate whether a standardized grape seed extract, compared to placebo, can significantly influence systolic blood pressure (SBP) in individuals with high-normal blood pressure (BP) who are adhering to a low-sodium Mediterranean diet. Additionally, the effects of the grape seed extract on diastolic blood pressure (DBP), other hemodynamic parameters, and the Perceived Stress Score will be assessed.
Recruiting
Interested in participating?
Request InfoKey information
Conditions
Age range
18 year–70 year
Sex eligibility
All sexes
Study type
Interventional
Phase
Not applicable
Primary location
Who can participate
Healthy volunteers accepted: No
Only the study team can determine whether someone qualifies for participation.
Inclusion criteria
- Male or female subjects aged ≥18 and ≤70 years;
- Subjects with high-normal blood pressure levels, defined as SBP 130-139 mmHg and/or DBP 85-89 mmHg (according to ESH criteria);
- Subjects with an estimated 10-year CVD risk <10% (as per the SCORE risk prediction algorithm of the European Society of Cardiology);
- Subjects capable of communicating, making themselves understood, and complying with the study requirements;
- Subjects who agree to participate in the study and have dated and signed the informed consent form.
Exclusion criteria
- Treatment with direct vasodilator drugs or supplements known to affect blood pressure levels;
- Chronic pharmacological treatments for any clinical condition not stabilized for at least 3 months;
- Known thyroid, renal, or hepatic dysfunction (including transaminase levels ≥3 times the upper limit of normal [ULN]);
- Current or past history of alcohol abuse;
- Pregnancy or breastfeeding;
- Known intolerance or hypersensitivity to the active ingredients of the investigational dietary supplement;
- History or clinical evidence of any significant concomitant disease that could compromise subject safety or the ability to complete the study.
Treatment and study plan
Standardized Grape Seed Extract
Dietary SupplementGrape seed dry extract standardized to provide: ≥95.0% of proanthocyanidins by spectrophotometry, ≥5.0% ≤15.0% of catechin and epicatechin by High-Performance Liquid Chromatography (HPLC)
Placebo
OtherPlacebo
Primary outcomes
-
Treatment-dependent change in SBP
Time frame: 8 weeks
The primary objective is to assess and compare the effect on SBP after 8 weeks of treatment with either a standardized grape seed extract or placebo, both administered alongside a low-sodium Mediterranean diet (SOC)
Secondary outcomes
-
Treatment-dependent change in SBP
Time frame: 4 weeks
To evaluate the effect of the standardized grape seed extract on changes in SBP compared to baseline and placebo after 4 weeks of treatment
-
Treatment-dependent change in DBP
Time frame: 4 weeks
To evaluate the effect of the standardized grape seed extract on changes in DBP compared to baseline and placebo after 4 weeks of treatment
-
Treatment-dependent change in DBP
Time frame: 8 weeks
To evaluate the effect of the standardized grape seed extract on changes in DBP compared to baseline and placebo after 8 weeks of treatment
-
Treatment-dependent change in Augmentation Index
Time frame: 8 weeks
To evaluate the effect of the standardized grape seed extract on changes in augmentation index compared to baseline and placebo after 8 weeks of treatment
-
Treatment-dependent change in cfPWV
Time frame: 8 weeks
To evaluate the effect of the standardized grape seed extract on changes in the carotid-femoral pulse wave velocity (cfPWV) compared to baseline and placebo after 8 weeks of treatment
-
Treatment-dependent change in VOI
Time frame: 8 weeks
To evaluate the effect of the standardized grape seed extract on changes in the vascular overload index (VOI) compared to baseline and placebo after 8 weeks of treatment
-
Treatment-dependent change in endothelial reactivity
Time frame: 8 weeks
Change in endothelial reactivity from baseline after 8 weeks of treatment with standardized grape seed extract, compared to placebo, as assessed using the Endocheck® module integrated into the Vicorder® system.
This method evaluates endothelium-dependent vasodilation through digital pulse volume (PV) analysis in response to reactive hyperemia. The outcome is expressed as the percent change (%) in pulse volume from baseline to peak post-occlusion values, serving as a validated surrogate marker of endothelial function.
-
Treatment-dependent change in arterial compliance
Time frame: 8 weeks
Change from baseline in arterial compliance, evaluated as the ratio between stroke volume (SV) and pulse pressure (PP) (SV/PP ratio), following 8 weeks of treatment with standardized grape seed extract compared to placebo.
-
Treatment-dependent change in the perfusion index
Time frame: 8 weeks
To evaluate the effect of the standardized grape seed extract on changes in perfusion index compared to baseline and placebo after 8 weeks of treatment
-
Treatment-dependent change in the perceived stress levels
Time frame: 8 weeks
Change from baseline in perceived stress levels after 8 weeks of treatment with standardized grape seed extract compared to placebo, measured using the Perceived Stress Scale (PSS) developed by Cohen and Williamson (1988).
The PSS is a validated 10-item self-report questionnaire that assesses the degree to which situations in one's life are appraised as stressful over the past month. The questions concern the participant's feelings and thoughts during the last month. For each item, the participant indicates how often they felt or thought a certain way by circling the frequency.
Scores range from 0 to 40, with higher scores indicating higher perceived stress levels. The outcome is expressed as the change in total PSS score from baseline.
Study contacts
Contact information is provided by the study sponsor or research team.
Sponsors and collaborators
Lead sponsor
Indena S.p.A
Industry
Registry information
Official study title
Hemodynamic Effects of a Standardized Grape Seed Extract Supplementation: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Clinical Trial
Acronym: ZENITH
Important dates
- Study start
- 2026
- Primary completion
- 2027
- Study completion
- 2027
- First posted
- Jul 29, 2025
- Registry last updated
- Apr 22, 2026
OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.
View the official ClinicalTrials.gov record (opens in a new tab)This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.
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