|- candidate number||1516|
|- NTR Number||NTR314|
|- Date ISRCTN created||20-dec-2005|
|- date ISRCTN requested||18-okt-2005|
|- Date Registered NTR||9-sep-2005|
|- Secondary IDs||project 2005.2 |
|- Public Title||Low dose vitamin K to improve therapeutic quality control of oral anticoagulant treatment: a randomized double-blind placebo controlled trial.|
|- Scientific Title||Low dose vitamin K to improve therapeutic quality control of oral anticoagulant treatment: a randomized double-blind placebo controlled trial.|
|- 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.
|- Healt Condition(s) or Problem(s) studied||Anticoagulants, Thrombosis, Embolus|
|- 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.
|- 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 expectedinterruption of oral anticoagulant treatment of more than 1 week;
5. Self-management of oral anticoagulant therapy;
6. Other drugs affecting hemostasis (aspirin, heparin, clopidogrel).
|- mec approval received||yes|
|- multicenter trial||no|
|- Type||2 or more arms, randomized|
|- planned startdate ||16-nov-2004|
|- planned closingdate||1-jun-2006|
|- Target number of participants||200|
|- Interventions||1. Treatment group: 100 microgram vitamin K for 24 weeks;|
2. Placebo group: placebo for 24 weeks.
|- Primary outcome||1. Quality of anticoagulant treatment;|
2. Expressed as time in therapeutic range.
|- Secondary outcome||1. Number of INRs in therapeutic range;|
2. Bleeding and thromboembolic complications.
|- Trial web site||N/A|
|- status||stopped: trial finished|
|- CONTACT FOR PUBLIC QUERIES|| Eva Rombouts|
|- CONTACT for SCIENTIFIC QUERIES||Dr. Felix J.M. Meer, van der|
|- Sponsor/Initiator ||Leiden University Medical Center (LUMC), Department of Hematology|
(Source(s) of Monetary or Material Support)
|Dutch Thrombosis Foundation|
|- Publications||J Thromb Haemost. 2007 Oct;5(10):2043-8. Epub 2007 Jul 31.|
|- Brief summary||Background:|
It has been shown that oral anticoagulant control is less stable at a low dietary intake of vitamin K.
We hypothesize that a low dose vitamin K supplement results in a more stable anticoagulation in patients using vitamin K antagonists.
The primary objective of this study:
is to test this hypothesis clinically.
The study is a double blind, randomized, placebo controlled trial in patients who use phenprocoumon and have an indication for long-term oral anticoagulant treatment.
Two hundred patients will be randomized to receive adjusted-dose phenprocoumon and a daily vitamin K supplement of 100 micrograms or to receive adjusted-dose phenprocoumon and placebo for 24 weeks.
The primary endpoint is the percentage of time the INR is within the therapeutic range.
|- Main changes (audit trail)|
|- RECORD||9-sep-2005 - 18-nov-2008|