Condition category
Haematological Disorders
Date applied
20/12/2005
Date assigned
20/12/2005
Last edited
15/08/2008
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information

Type

Scientific

Primary contact

Dr F.J.M. van der Meer

ORCID ID

Contact details

Leiden University Medical Center
Department of Hematology
P.O. Box 9600
Leiden
2300 RC
Netherlands
+31 (0)71 5263901
f.j.m.van_der_meer@lumc.nl

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

Project 2005.2; NTR314

Study information

Scientific title

Acronym

Study hypothesis

1. Oral anticoagulant control is less stable at a low average intake of vitamin K
2. As a consequence, a low dose vitamin K supplement results in a more stable anticoagulant effect in patients using vitamin K antagonists (VKA)
3. Dietary intake of vitamin K is associated with sensitivity to VKA and stability of anticoagulant treatment
4. Polymorphisms of the VKORC1 gene are associated with sensitivity to VKA and stability of anticoagulant treatment

Ethics approval

Ethics approval received from the local medical ethics committee

Study design

Randomised, double-blinded, placebo controlled parallel group trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Condition

Thrombosis, emboly, anticoagulant treatment

Intervention

1. Treatment group: 100 microgram vitamin K for 24 weeks
2. Placebo group: placebo for 24 weeks

Intervention type

Supplement

Phase

Not Specified

Drug names

Vitamin K

Primary outcome measures

1. Quality of anticoagulant treatment
2. Expressed as time in therapeutic range

Secondary outcome measures

1. Number of international normalised ratios (INRs) in therapeutic range
2. Bleeding and thromboembolic complications

Overall trial start date

16/11/2004

Overall trial end date

01/06/2006

Reason abandoned

Eligibility

Participant inclusion criteria

1. Patients treated at the Leiden anticoagulation clinic with an indication for long-term oral anticoagulant therapy using the vitamin K antagonist phenprocoumon
2. Age between 18 and 80 years
3. Informed consent

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

200

Participant exclusion criteria

1. Treatment by a medical specialist for liver failure
2. Haemo or peritoneal dialysis
3. Pregnancy or a planned pregnancy, puerperium
4. Any chronic condition with an expected median survival of less than 6 months
an expected interruption of oral anticoagulant treatment of more than 1 week
5. Self-management of oral anticoagulant therapy
6. Other drugs affecting haemostasis (aspirin, heparin, clopidogrel)

Recruitment start date

16/11/2004

Recruitment end date

01/06/2006

Locations

Countries of recruitment

Netherlands

Trial participating centre

Leiden University Medical Center
Leiden
2300 RC
Netherlands

Sponsor information

Organisation

Leiden University Medical Center (LUMC) (The Netherlands)

Sponsor details

Department of Hematology
P.O. Box 9600
Leiden
2300 RC
Netherlands

Sponsor type

Charity

Website

http://www.lumc.nl/english/start_english.html

Funders

Funder type

Charity

Funder name

Dutch Thrombosis Foundation (Trombosestichting Nederland) (The Netherlands)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes