Study on the effectiveness of a dietary supplement containing grape pomace extract and L-arginine for blood pressure control in people with mild to moderate hypertension
| ISRCTN | ISRCTN99673579 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN99673579 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | Nil known |
| Sponsor | NGN Healthcare—New Generation Nutraceuticals s.r.l. |
| Funder | NGN Healthcare—New Generation Nutraceuticals s.r.l. |
- Submission date
- 25/09/2025
- Registration date
- 17/11/2025
- Last edited
- 17/11/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Circulatory System
Plain English summary of protocol
Background and study aims
High blood pressure (hypertension) is a common condition that increases the risk of heart disease, stroke, and other health problems. Currently, there is growing interest in safe, natural alternatives that may help reduce blood pressure. This study aims to evaluate whether a food supplement containing a grape seed extract rich in natural antioxidants and L-arginine (an amino acid that helps blood vessels relax) can improve blood pressure control in people with mild to moderate hypertension.
Who can participate?
Adults (men and women) of caucasian ethnicity, aged 18 to 75 years, living in Italy, with a documented diagnosis of mild or moderate essential hypertension. Participants must already be on stable antihypertensive therapy that will not be changed during the study.
What does the study involve?
A total of 296 participants will be randomly divided into four groups:
1. Mild hypertension: one tablet per day of the supplement
2. Moderate hypertension: two tablets per day of the supplement
3. Mild hypertension: one tablet per day of a placebo (inactive substance)
4. Moderate hypertension: two tablets per day of a placebo
The treatment period will last 12 weeks, followed by a 4-week follow-up period without tablets. Participants will have their blood pressure measured regularly. At the start and end of treatment, blood and urine samples will be collected to measure cholesterol, blood sugar, kidney and liver function. Participants will also complete a short quality-of-life questionnaire.
The study will begin after approval by the Ethics Committee and the Italian Ministry of Health. Each participant will be followed for about 20 weeks in total (including run-in, treatment, and follow-up).
What are the possible benefits and risks of participating?
The ingredients of the supplement and the placebo are legally authorised for use in food supplements. No serious risks are expected. Participants may benefit from improved blood pressure control and better quality of life. Participants will be carefully monitored, and any suspected adverse reactions will be reported to the national surveillance system.
Where is the study run from?
The study is being conducted at the COMEGEN medical cooperative in Naples, Italy, under the supervision of Dr Matteo Laringe (General Practitioner).
When is the study starting and how long is it expected to run for?
April 2025 to September 2025
Who is funding the study?
The study is sponsored and funded by NGN Healthcare s.r.l.
Who is the main contact?
Dr Matteo Laringe, comegen@comegen.org
Contact information
Principal investigator
Via Maria Bakunin, 41
Naples
80126
Italy
| Phone | + 39 3939406629 |
|---|---|
| matteo.laringe@gmail.com |
Scientific
Via Domenico Montesano, 49
Naples
80131
Italy
 ORCID ID |
0000-0002-0251-9936 |
|---|---|
| Phone | +39 81678607 |
| giancarlo.tenore@unina.it |
Public
Via Campana 173
Quarto
80010
Italy
| Phone | 3405387058 |
|---|---|
| elisabetta.schiano@unina.it |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Randomized double-blind placebo-controlled parallel-group clinical trial |
| Secondary study design | Randomised parallel trial |
| Participant information sheet | 48067_PIS_V1.0_14Jan2025.pdf |
| Scientific title | A randomized, double-blind, placebo-controlled trial to evaluate the effects of grape pomace extract and L-arginine supplementation on blood pressure in individuals with mild to moderate hypertension |
| Study acronym | FLUTAREG |
| Study objectives | This study hypothesizes that supplementation with a dietary product containing grape pomace extract and L-arginine will significantly reduce blood pressure in individuals with mild to moderate hypertension. The active components, particularly the polyphenols found in grape pomace extract and the nitric oxide precursor L-arginine, are believed to improve vascular function and increase nitric oxide production, which plays a crucial role in regulating blood pressure. By enhancing endothelial function and reducing oxidative stress, this combination is expected to normalize systolic and diastolic blood pressure values over the 12-week treatment period. Additionally, the study aims to evaluate secondary outcomes, including improvements in lipid profiles, kidney function, and quality of life, which are often impaired in hypertensive individuals. |
| Ethics approval(s) |
Approved 29/04/2025, Campania Territorial Ethics Committee 1 (Comitato Etico Territoriale Campania 1) (Via Mariano Semmola 52, Naples, 80131, Italy; +39 081 590 31 11; comitatoetico@istitutotumori.na.it), ref: n° 5/25 of 29/04/2025 |
| Health condition(s) or problem(s) studied | Mild to moderate essential hypertension |
| Intervention | Participants in this study are randomly assigned to one of four groups: - Group 1: Individuals with grade 1 hypertension (systolic BP 130-150 mmHg, diastolic BP 90-95 mmHg) receive one tablet per day containing 300 mg of grape pomace extract and 200 mg of L-arginine. - Group 2: Individuals with grade 2 hypertension (systolic BP 151-170 mmHg, diastolic BP 96-105 mmHg) receive two tablets per day of the same formulation. - Group 3: Individuals with grade 1 hypertension receive one tablet per day of the placebo, consisting of maltodextrin. - Group 4: Individuals with grade 2 hypertension receive two tablets per day of the placebo. Randomization is performed using a simple randomization method with a 1:1:1:1 allocation ratio. The treatment groups are blinded, and neither the participants nor the study staff are aware of the assigned treatments (double-blind design). All treatments are provided free of charge. The intervention lasts 12 weeks, with participants taking the assigned treatment daily. |
| Intervention type | Supplement |
| Primary outcome measure(s) |
Blood pressure measured using sphygmomanometer at baseline, 4, 8, and 12 weeks of treatment, and at the end of the 4-week follow-up period. |
| Key secondary outcome measure(s) |
1. Fasting blood glucose measured using a blood glucose meter at baseline, 4, 8, and 12 weeks of treatment, and at the end of the 4-week follow-up period |
| Completion date | 20/09/2025 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 75 Years |
| Sex | All |
| Target sample size at registration | 300 |
| Total final enrolment | 296 |
| Key inclusion criteria | 1. Male and female subjects, of caucasian ethnicity, resident in Italy, aged 18–75 years 2. Documented diagnosis of essential hypertension for at least one year before study initiation 3. Ongoing treatment with antihypertensive medications that will not be modified during the study 4. No additional cardiological (e.g., atrial fibrillation, heart failure) or metabolic (e.g., diabetes, dyslipidaemia) comorbidities 5. Ability to understand the study procedures and to provide written informed consent |
| Key exclusion criteria | 1. Any autoimmune, rheumatologic or vascular disease other than essential hypertension 2. Severe hypertension (grade 3: ≥171/106 mmHg) 3. Diabetes mellitus 4. Irregular sleep/wake rhythm (e.g., night-shift workers within the last 3 months) 5. Total cholesterol >250 mg/dl or triglycerides >200 mg/dl 6. Cardiovascular events (myocardial infarction and/or stroke) in the past 6 months 7. Renal impairment (serum creatinine >1.5 mg/dl) or hepatic impairment (ALT/AST and/or γ-GT twice above normal values) 8. Anaemia (Hb <12 g/dl) or other chronic diseases 9. Habitual intense physical activity 10. Gastrointestinal disorders 11. Body weight variation >3 kg in the 3 months before enrolment 12. Malignant neoplasms 13. Significant neurological or psychiatric disorders, including alcohol or drug abuse 14. Concomitant therapy with: hypoglycaemic agents, laxatives, cyproheptadine, antidepressants, antiserotonergic drugs, phenothiazines, barbiturates, oral corticosteroids, or antipsychotics 15. Pregnancy or breastfeeding 16. Women of childbearing potential not using adequate contraception |
| Date of first enrolment | 05/05/2025 |
| Date of final enrolment | 02/06/2025 |
Locations
Countries of recruitment
- Italy
Study participating centre
Naples
80126
Italy
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Available on request |
| IPD sharing plan | The datasets generated during and/or analysed during the current study will be available upon reasonable request from Prof Gian Carlo Tenore, giancarlo.tenore@unina.it • The type of data that will be shared: the data that will be shared includes anonymized data related to the primary and secondary outcome measures. • Timing for availability: the data will be made available upon publication of the study results for a timeless period following publication. • Consent from participants: the participant information sheet is attached to the present registration, together with the study synopsis. • Data anonymization: all shared data will be fully anonymized to ensure participants' privacy. This will involve removing all personal identifiers in compliance with the General Data Protection Regulation (GDPR). • Ethical or legal restrictions: No significant ethical or legal restrictions have been identified at this time. Data sharing complies with ethical approval received from the Campania Territorial Ethics Committee 1 (ref: n° 5/25 of 29/04/25). |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | version 1.0 | 14/01/2025 | 01/10/2025 | No | Yes |
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
| Protocol file | version 1.0 | 14/01/2025 | 01/10/2025 | No | No |
Additional files
- 48067_PIS_V1.0_14Jan2025.pdf
- Participant information sheet
- 48067_Protocol_v1.0_14Jan2025.pdf
- Protocol file
Editorial Notes
26/09/2025: Study's existence confirmed by the Campania Territorial Ethics Committee 1 (Comitato Etico Territoriale Campania 1).
