Vitamin K in kidney transplant organ recipients: Investigating the effect on vessel stiffness
| ISRCTN | ISRCTN22012044 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN22012044 |
| Protocol serial number | GN16RE696 |
| Sponsor | NHS Greater Glasgow and Clyde |
| Funders | Kidney Research UK, Darlinda's Charity for Renal Research |
- Submission date
- 20/09/2017
- Registration date
- 26/09/2017
- Last edited
- 22/03/2021
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Surgery
Plain English summary of protocol
Background and study aims
Reduced kidney function (sometimes called chronic kidney disease) is common, especially as people get older. Kidney problems don’t just affect the kidney, but can affect the health of blood vessels and the heart, leading to an increased risk of heart disease or strokes. After a kidney transplant, this risk of heart disease is reduced a little bit, but patients with kidney transplants are still at higher risk compared to the general population. Kidney problems also lead to blood vessels becoming stiffer than usual, due to a build-up of calcium (rather like chalk) in the wall of the blood vessel. There are no good treatments for this problem yet. Some recent research suggests that vitamin K—a vitamin present in vegetables and dairy foods—might be able to slow down or stop this build-up of calcium in blood vessels. The aim of this study is to examine whether giving extra vitamin K, which is also known as menadiol diphosphate, can affect blood vessel stiffness (which is linked to improving cardiovascular health and survival) and other measures of heart and vessel health.
Who can participate?
Adults aged 18 and older in the Glasgow area who have had a functioning kidney transplant for a year or more will be taking part.
What does the study involve?
Participants are randomly allocated to one of two groups, to receive either a vitamin K or placebo capsule three times per week. There are up to five visits to the hospital in this time, and up to two additional, brief meetings to hand out more study medication, like collecting a prescription. Most participants have have a screening visit combined with a baseline visit, and if happy to participate, have blood and urine tests taken, blood vessel stiffness measured using a small, plastic pencil-shaped device and inflatable cuffs placed on the arm and the leg, and they will attend for an MRI and CT scan of the heart, to measure blood vessel stiffness and calcification. They have transplant function and immunosuppression levels checked one month after starting to ensure the medication is not interfering with their renal transplant (this is not expected). Participants attend for a review - without any additional tests - at 6 months, when they are given more study medication. The final review takes place at 12 months when all the baseline tests are repeated.
What are the possible benefits and risks of participating?
The dose of vitamin K has been used before and is known to be safe. There is a small excess risk of jaundice (yellow appearance of your skin), more common in participants with a particular genetic condition, and people with this condition will not be able to participate in the study. Some participants may experience some bruising or discomfort when having blood tests taken. Some people find the blood pressure cuff a little uncomfortable. The MRI scan is conducted in a narrow tunnel that can be quite noisy, and some people may find this claustrophobic. We ask for two CT scans of the heart and large vessels during the study. These CT scans expose participants to a small amount of radiation, equivalent to the amount the average person is exposed to in 4-6 months from natural sources in the environment. The excess radiation exposes you to a tiny increased risk of developing cancer of 1 in 9000. This is equivalent to the risk of dying from an insect bite.
Where is the study run from?
University of Glasgow, Scotland (UK)
When is the study starting and how long is it expected to run for?
September 2017 to August 2018
Who is funding the study?
1. Kidney Research UK (UK)
2. Darlinda's Charity for Renal Research (UK)
Who is the main contact?
Dr Jennifer Lees
jennifer.lees@glasgow.ac.uk
Contact information
Public
Room 312
BHF GCRC
University of Glasgow
126 University Avenue
Glasgow
G12 8TA
United Kingdom
 ORCID ID |
0000-0001-6331-0178 |
|---|---|
| Phone | +44 141 330 2409 |
| jennifer.lees@glasgow.ac.uk |
Scientific
Room 312
BHF GCRC
University of Glasgow
126 University Avenue
Glasgow
G12 8TA
United Kingdom
| Phone | +44 141 330 2409 |
|---|---|
| jennifer.lees@glasgow.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Single-centre parallel-group randomised double-blind placebo-controlled trial of vitamin K4 (Menadiol diphosphate) versus placebo |
| Secondary study design | Randomised controlled trial |
| Study type | Participant information sheet |
| Scientific title | Vitamin K in kidney Transplant Organ Recipients: Investigating vEssel Stiffness |
| Study acronym | ViKTORIES |
| Study objectives | Hypothesis: 1. Vitamin K supplementation in renal transplant patients will reduce markers of vascular stiffness and calcification in prevalent renal transplant patients compared with placebo. 2. There will be secondary beneficial effects on transplant function and LV mass/cardiac fibrosis as assessed by magnetic resonance imaging. |
| Ethics approval(s) | West of Scotland Research Ethics Committee 4, 22/06/2017, ref: 17/WS/0101 |
| Health condition(s) or problem(s) studied | Renal transplant recipients |
| Intervention | Most participants have a screening visit combined with a baseline visit, and if happy to participate, have blood and urine tests taken, blood vessel stiffness measured using a small, plastic pencil-shaped device and inflatable cuffs placed on the arm and the leg, and they will attend for an MRI and CT scan of the heart, to measure blood vessel stiffness and calcification. Participants are randomised to consuming either identical capsules containing vitamin K4 (menadiol diphosphate) 5mg or placebo to be taken three times per week. Participants are randomised in a 1:1 ratio to vitamin K4 or placebo by a computer-generated randomisation programme (generated by Sealed Envelope: https://sealedenvelope.com/) in random permuted blocks. The total duration of treatment and follow-up is 12 months for both vitamin K4 and placebo groups. There are up to 5 visits to the hospital in this time, and up to two additional, brief meetings to hand out more study medication, like collecting a prescription. They have transplant function and immunosuppression levels checked one month after starting to ensure the medication is not interfering with their renal transplant (this is not expected). Participants attend for a review - without any additional tests - at 6 months, when they are given more study medication. The final review takes place at 12 months when all the baseline tests are repeated. |
| Intervention type | Drug |
| Phase | Phase II |
| Drug / device / biological / vaccine name(s) | Vitamin K4 (Menadiol diphosphate) |
| Primary outcome measure(s) |
Vascular stiffness is measured using the aortic distensibility on MRI scan at 12 months of treatment. |
| Key secondary outcome measure(s) |
1. Carotid-femoral pulse wave velocity is measured using SphygmoCor XCEL PWA & PWV system at 12 months of treatment |
| Completion date | 18/08/2019 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Sex | All |
| Target sample size at registration | 90 |
| Total final enrolment | 90 |
| Key inclusion criteria | 1. Male or female of non-child-bearing potential aged 18 years or over 2. Functioning renal transplant, transplanted > 12 months 3. eGFR >15ml/min by CKD-EPI equation |
| Key exclusion criteria | 1. Inability to give written informed consent 2. Atrial fibrillation 3. Taking warfarin (vitamin K antagonist) 4. Taking vitamin K or indication for vitamin K 5. Allergy or intolerance to gelatine, lactose or cellulose 6. Breast-feeding or women of child-bearing potential 7. Glucose-6-phosphate dehydrogenase (G6PD) deficiency 8. Life expectancy <12 months 9. Contraindications to MRI scan |
| Date of first enrolment | 26/09/2017 |
| Date of final enrolment | 26/06/2018 |
Locations
Countries of recruitment
- United Kingdom
- Scotland
Study participating centre
Glasgow
G12 8TA
United Kingdom
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|---|
| IPD sharing plan summary | Data sharing statement to be made available at a later date |
| IPD sharing plan | The datasets generated during and/or analysed during the current study are/will be available upon request after study results have been published. Specific data sharing plans to be confirmed and will be made available at a later date. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Results article | 01/03/2021 | 22/03/2021 | Yes | No | |
| Protocol article | protocol | 01/07/2020 | 25/11/2020 | Yes | No |
| HRA research summary | 28/06/2023 | No | No | ||
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
Editorial Notes
22/03/2021: The following changes were made to the trial record:
1. Publication reference added.
2. The total final enrolment was added.
25/11/2020: Publication reference added.
06/09/2018: The recruitment end date has been changed from 04/07/2018 to 26/06/2018
