Evaluation of Maintenance Dosing vs Loading Dosing Upon Restarting Warfarin Therapy: A Prospective Randomized Trial

NCT01124058 | Completed Phase 1

• 1 other identifier: 2007UHFMDvsLD
• Study Type: interventional
• Target: 39
• Locations: 1 country
• Sites: 1

Brief Summary

A prospective, randomized trial to compare the time taken to achieve a therapeutic INR upon re-starting warfarin at a "loading" dose (namely 1.5 times the "maintenance" dose for 3 days) compared to the known "maintenance" dose.

Conditions

Anticoagulation

Keywords

restarting warfarin; time to therapeutic INR

Outcome Measures

Primary Outcomes (1)

• re-starting warfarin "loading" dose vs "maintenance" dose

  To compare the time taken to achieve a therapeutic INR between those patients re-starting warfarin with a "loading" dose and a "maintenance" dosing regimen using linear interpolation of INRs.

  INR drawn 3 days post-reinitiation and then every 2 days until therapeutic

Secondary Outcomes (3)

• Compare % of time within, above and below the target INR range

  days

• Compare bleeding/clotting complications between two groups

  30 days, 90 days

• Compare the levels of protein C, protein S, and factor II between 2 groups.

  week

Study Arms (2)

Loading

EXPERIMENTAL

1.5 times the maintenance dose for 3 days, then resumption of warfarin dosing as per the maintenance dose

Drug: warfarin

Maintenance

ACTIVE COMPARATOR

Re-start same dose as previously stable on

Drug: Warfarin

Interventions

Warfarin DRUG

Patients will be randomized to re-start warfarin at their "maintenance" dose or at a "loading" dose (1.5 times the maintenance dose for 3 days, then resumption of warfarin dosing as per the maintenance dose).

Also known as: warfarin, Taro-warfarin, Apo-warfarin, Coumadin, Fragmin, Low-molecular weight heparin

Loading

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Have 'stable warfarin maintenance dosing' (defined as last 2 INRs within therapeutic range with weekly warfarin dosing not being changed any more than 10%)
• Have an INR indicative of not taking any warfarin (INR \<1.4) or confirmation of the patient not taking any warfarin in the past 4 days
• Provide written, informed consent

Sponsors & Collaborators

• University of Alberta: lead

Study Sites (1)

Univeristy of Alberta

Edmonton, Alberta, T6G 2C8, Canada

Location

MeSH Terms

Interventions

Warfarin; Dalteparin

Intervention Hierarchy (Ancestors)

4-Hydroxycoumarins; Coumarins; Benzopyrans; Pyrans; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heparin, Low-Molecular-Weight; Heparin; Glycosaminoglycans; Polysaccharides; Carbohydrates

Study Officials

• Tammy J Bungard, BSP, PharmD

  Univeristy of Alberta

  PRINCIPAL INVESTIGATOR

• Bruce Ritchie, MD, FRCPC

  University of Alberta

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: May 13, 2010
• First Posted: May 14, 2010
• Study Start: July 1, 2010
• Primary Completion: August 1, 2012
• Study Completion: August 1, 2012
• Last Updated: October 25, 2017

Record last verified: 2017-10

Locations

CA (1)