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NCT Number: NCT06940011

Endocalyx in Treatment Resistent Hypertension

The goal of this randomized, double-blind, placebo-controlled study is to assess whether the food supplement Endocalyx lowers blood pressure in patients with treatment resistant hypertension.

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Key information

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Amsterdam UMC

Amsterdam, North Holland, 1105 AZ, Netherlands

Location status: Recruiting

Location contact

C.L. Zwager, MD

SUB_INVESTIGATOR

R.H.G Olde Engberink, Nephrologist

PRINCIPAL_INVESTIGATOR

Rik Olde Engberink, MD PhD

CONTACT

[email protected]

+31(0)205661930

S.S.A Simon, MD

SUB_INVESTIGATOR

Sanédy Simon, MD

CONTACT

[email protected]

+31(0)20567789

About this study

During this intervention study, subjects will receive either a placebo or Endocalyx for 12 weeks. The main objective of this study is to assess whether the food supplement Endocalyx lowers blood pressure in patients with treatment resistant hypertension.

Secondary objectives are:

  • Change from baseline in office blood pressure and 24-hour blood pressure profiles in subjects with treatment resistant hypertension.
  • To assess whether sodium intake, sex or kidney function modulates the effect of Endocalyx on blood pressure.
  • Change from baseline in total vessel density, perfused vessel density, proportion of perfused vessels and microvascular health score
  • To assess the effect of Endocalyx on total peripheral resistance.
  • The effect of Endocalyx on quality of life.
  • To estimate the potential impact of Endocalyx on long-term cardiovascular protection and health care costs.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Treatment resistant hypertension defined as
  • an uncontrolled office BP (≥140/90 mmHg).
  • is on a regimen of ≥3 adequately dosed antihypertensive agents of different classes, including a diuretic, at maximum tolerated dose based on investigator judgment.
  • Stable diuretic and antihypertensive treatment for the previous 3 weeks.
  • Subject, or legal representative, has voluntarily signed and dated an Informed Consent Form, approved by the Independent Ethics Committee (IEC).

Exclusion criteria

  • Age <18 years.
  • Estimated glomerular filtration rate (eGFR) <20 ml/min/1.73m2 measured by the 2021 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine formula and the 2012 cystatin C CKD-EPI formula.
  • A mean seated systolic blood pressure of at least 180 mmHg or a diastolic blood pressure of at least 110 mmHg.
  • Known secondary hypertension
  • An acute coronary syndrome, stroke, transient ischemic attack or cardiovascular surgery in the last 3 months.
  • Hospitalization for heart failure in the past 3 weeks.
  • Dialysis treatment or expected initiation of dialysis within 3 months of screening.
  • Women of child bearing potential who are not taking adequate contraception (i.e. <1% failure rate).
  • Planned surgery in the next 12 weeks
  • Major surgery in the previous 4 weeks.
  • Use of prednisolone >5 mg/day
  • Use of any other investigational drug.
  • Presence of significant comorbidities (e.g., advanced malignancy, advanced liver disease) with a life expectancy of less than 1 year.
  • A psychiatric, addictive or any disorder that compromises ability to give truly informed consent for participation in this study.
  • Known hypersensitivity to seaweed, corn, artichoke, grape, melon or to any of the excipients of Endocalyx.
  • Known hypersensitivity or allergies for milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat and soybeans.
  • Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose galactose malabsorption.

Treatment and study plan

Endocalyx Pro

Dietary Supplement

4 capsules once daily OR 2 capsules twice daily

Placebo

Other

4 capsules once daily OR 2 capsules twice daily

Primary outcomes

  1. Change from baseline in 24-hour systolic blood pressure

    Time frame: 12 weeks

    We will perform an uncorrected analysis and an analysis that is corrected for the reported and measured changes in antihypertensive medication use.

Secondary outcomes

  1. Change from baseline in 24-hour diastolic blood pressure

    Time frame: 12 weeks

  2. Change from baseline in seated systolic office blood pressure

    Time frame: 12 weeks

  3. Change from baseline in seated diastolic office blood pressure

    Time frame: 12 weeks

  4. Change from baseline in percentage of patients with a night-time blood pressure dip

    Time frame: 12 weeks

    The nighttime blood pressure dipping status will be measured with a 24-hour blood pressure measurements. Patients will be classified as a 'dippers' when the nighttime systolic blood pressure and/or diastolic blood pressure falls >10% and <20% compared to daytime readings. Exteme dippers are described as those with blood pressure fall of at least 20%. Patients with blood pressure fall between 0 and 10% are classified as non-dippers.

  5. Percentage of patients achieving a seated office blood pressure <140/90 mmHg after intervention

    Time frame: 12 weeks

    Participants achieved a response if the systolic blood pressure is below 140 mmHg and the diastolic blood pressure is below 90 mmHg

  6. Percentage of patients that needed additional antihypertensive drugs and/or higher dosage of antihypertensive drugs during the study

    Time frame: 12 weeks

  7. Percentage of patients that required lowering of their antihypertensive drugs during the study

    Time frame: 12 weeks

  8. Change from baseline in total vessel density and perfused vessel density

    Time frame: 12 weeks

    The total vessel density and perfused vessel density will be measured using Sidestream Dark Field imaging.

  9. Change from baseline in proportion of perfused vessels

    Time frame: 12 weeks

    The proportion of perfussed vessels will be measured using Sidestream Dark Field imaging.

  10. Change from baseline in microvascular flow index

    Time frame: 12 weeks

    The microvascular flow index will be measured using Sidestream Dark Field imaging.

  11. Change from baseline in microvascular health score

    Time frame: 12 weeks

    The microvascular health score will be measured using Sidestream Dark Field imaging.

  12. Change from baseline in heart rate

    Time frame: 12 weeks

    The heart rate will be measured using the Nexfin device

  13. Change from baseline in total peripheral resistance

    Time frame: 12 weeks

    The total pheripheral resistance will be measured using the Nexfin device

  14. Change from baseline in cardiac output

    Time frame: 12 weeks

    The cardiac output will be measured using the Nexfin device

  15. Change from baseline in quality of life

    Time frame: 12 weeks

    Quality of life will be evaluated by the SF-36 questionnaire.

  16. The potential impact of Endocalyx on long-term cardiovascular protection and health care costs.

    Time frame: 12 weeks

    The EQ-5D-5L questionnaire will be used to score a patient health status and will be transposed in quality adjusted life years (QALY's).

  17. Change from baseline in skin sodium content

    Time frame: 12 weeks

    Skin sodium content will measured using a 7T sodium MRI

  18. Change from baseline in muscle sodium content

    Time frame: 12 weeks

    Muscle sodium content will measured using a 7T sodium MRI

  19. Change from baseline in skin water content

    Time frame: 12 weeks

    Skin water content will measured using a 7T H-MRI

  20. Change from baseline in muscle water content

    Time frame: 12 weeks

    Muscle water content will measured using a 7T H-MRI

  21. Change from baseline in transepidermal water loss

    Time frame: 12 weeks

    Transepidermal water loss will be measured with the Tewameter® TM Hex probe

  22. Change from baseline in skin hydration

    Time frame: 12 weeks

    The skin hydration will be measured using the Corneometer® CM 825 probe

  23. Change from baseline in total body water

    Time frame: 12 weeks

    The change in total body water (liter) will be measured using the bioelectrical impendance analysis

  24. Incidence of adverse events in the Endocalyx group compared to the placebo group

    Time frame: 12 weeks

Other outcomes

  1. To assess whether sodium intake, measured using 24-hour urine collection, modulate the effect of Endocalyx on blood pressure.

    Time frame: 12 weeks

    We will study the (possible) modulatory effect sodium intake (mmol/L), measuring using 24 hours urine collection, on the effect of endocalyx on blood pressure.

  2. To assess whether sex modulate the effect of Endocalyx on blood pressure.

    Time frame: 12 weeks

    The association between sex and the effect of endocalyx on blood pressure.

  3. To assess whether kidney function modulate the effect of Endocalyx on blood pressure.

    Time frame: 12 weeks

    The association between kidney function and the effect of endocalyx on blood pressure.

Study contacts

Contact information is provided by the study sponsor or research team.

Rik Olde Engberink, MD PhD

CONTACT

[email protected]

0031205661930

Sanédy Simon, MD

CONTACT

[email protected]

0031205667789

Sponsors and collaborators

Lead sponsor

Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)

Other

Collaborators

  • Dutch Heart Foundation
  • Dutch Kidney Foundation
  • Microvascular Health Solutions LLC

Registry information

Official study title

Glycocalyx Restoration in Treatment Resistant Hypertension: a Proof of Concept, Randomized, Double-blind, Placebo-controlled Study

Acronym: GLYCO-TRH

Important dates

Study start
2025
Primary completion
2027
Study completion
2028
First posted
Apr 23, 2025
Registry last updated
Apr 23, 2025

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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