Does low dose oral vitamin K reduce the risk of bleeding, without causing thrombosis, in patients with warfarin-associated coagulopathy: a randomised clinical trial

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN16632843

Enrollment

660

Registered

2004-07-22

Start date

2004-09-01

Completion date

Unknown

Last updated

2019-02-11

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Coagulopathy due to warfarin therapy Haematological Disorders Other coagulation defects

Interventions

Randomised patients (with INR between 4.5 and 10) will receive either low-dose oral vitamin K, or matching placebo, and will be followed for thrombosis and bleeding outcomes. Patients

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1. 660 patients of either sex 2. Aged 18 and over 3. With International Normalised Ratio (INR) values of 4.5 to 10.0 and for cohort study: patients with INR values greater than 10

Exclusion criteria

Exclusion criteria: 1. Active bleeding 2. Geographic inaccessibility and lack of informed consent 3. Age less than 18 years 4. Warfarin is being discontinued 5. Vitamin K allergy

Design outcomes

Primary

Measure	Time frame
Proportion of patients with bleeding in each arm.	—

Secondary

Measure	Time frame
1. Major haemorrhage, or all clinically overt hemorrhage thrombosis and a composite of these two measures 2. Changes in INR values 3. Cost effectiveness	—

Countries

Canada, Italy, United States of America

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026